With five provinces already being declared drought disaster areas, the impact of the current drought is devastating. Not only is food security threatened but many farmers may face serious financial trouble if they are unable to meet their financial obligations. For many farmers, the situation is looking as bleak as the land around them... Read more
With five provinces already being declared drought disaster areas, the impact of the current drought is devastating. Not only is food security threatened but many farmers may face serious financial trouble if they are unable to meet their financial obligations. For many farmers, the situation is looking as bleak as the land around them.
South Africa is considered an arid country that is naturally prone to drought. The El Niño phenomenon has a profound effect on the climate of South Africa, with drought conditions experienced every 2 to 7 years. The effect ranges from mild to severe with some areas more severely affected than other areas. There are three types of droughts: protein drought seen in winter months when only protein is deficient, protein and energy drought when protein and energy are deficient and total drought, when there is no available roughage. All have major impacts on farming, and will require supplementation for animals to maintain condition.
While many farmers know to sell surplus animals in times of total droughts, the current situation is under immense strain as the markets are currently full, and animals are too thin and weak to sell. It takes a long time before farms completely recover from a drought. Animals and the veld can take several months to recover while feed prices need to stabilise and herd numbers replenished. It is always important for farmers to be proactive and plan for the next possible drought to the extent that when drought conditions occur, they will already have management plans in place.
A first step when planning for drought is proper record-keeping of stock, farm inputs and outputs. Keeping stock records help farmers to track the progress of their animals and place them into groups. When drought becomes an imminent problem, they are sold off in their different groups at different times. This is necessary to adjust the stocking rate to the veld carrying capacity, which declines during times of droughts. Animals require supplement feeding before they lose 15 % of their body weight. Older and unproductive animals should be sold first to cut feeding costs, and help in providing finances to acquire additional feed. The breeding herd should be spared as much as possible to start with replenishing stocks, as soon as the drought is over.
Keeping up to date with weather and agricultural news as well as social media and market trends and market prices will all assist with drought planning. AgriSuite Online® can assist users with valuable information on current weather conditions, market prices and management information to help prepare farmers for times of drought.
Unfortunately, the current drought will not be the only one experienced during most farmers' lifetimes. Based on the current drought conditions, farmers must consider the lessons they have learnt (or will still learn), and apply them to future strategies to survive droughts. Farmers that have a plan in place will not only be prepared and successfully pull through a drought, but they will be in a position to assist other farmers through own experience and knowledge.
Citrus black spot (CBS) is a fungal disease caused by Guignardia citricarpa that affects citrus and some other fruit species. It symptoms are spots and blemishes, particularly on the fruit. Lemons are most susceptible... Read more
Citrus black spot (CBS) is a fungal disease caused by Guignardia citricarpa that affects citrus and some other fruit species. It symptoms are spots and blemishes, particularly on the fruit. Lemons are most susceptible, and predictably the disease first appears on this species in unaffected regions [2].
The disease was first noted in Australia at the turn of the last century and spread to South Africa 60 years ago. One feature of the disease is that the fungus may be present for many years in an area before the symptoms appear; it may take 5 to 30 years from when the symptoms are noted to when the disease reaches epidemic proportions and control measures are necessary. In Zimbabwe, it reached epidemic proportions 30 years after becoming well established in the Limpopo area. Another feature of the disease is that, although it advances slowly, it never declines or disappears once it has reached epidemic levels. The establishment and development of the disease depend on the climatic conditions and is assisted by the presence of the more susceptible species - lemon [2].
CBS predominantly infects the fruit causing unsightly lesions spoiling their sales appeal. However, the disease seldom causes post-harvest decay or affects the internal quality of the fruit; that is, it has a cosmetic effect that reduces the market value of the citrus. Marketing is further complicated because harvested fruit can be infected but not show any spots or blemishes. Spots and blemishes develop during storage and distribution, resulting in the market down-grading or rejecting the fruit.
All these issues involving CBS are reasons why countries that grow citrus, but do not have the disease, impose strict phyto-sanitary regulations at their borders. Globally the disease is wide-spread but it has never become established in Europe, North America, Central America or the Caribbean [4]. South Africa exports more than 40% of its citrus to the European Union, but it does this under strict regulations requiring farmers to use disease control strategies including chemical spraying. To keep up these sanitary measures it costs farmers over R1 billion annually. Consequently, the necessity of these EU regulations is frequently questioned by the farmers, their associations and the government.
The logic for this questioning arises from the influence of climatic conditions on the life cycle of the disease. Leaves on citrus trees growing during the summer become infected with the fungus and drop to the ground later in the season. This leaf-litter has fungal spores on it in a dormant state. At the start of the following season, the spores are dispersed by rain droplets. They are not airborne as such but carried by droplets onto the developed fruit low-hanging fruit is more susceptible. Susceptibility to infection lasts for a short three month period, from about November to January.
Thus citrus, growing in a Mediterranean climate without summer rainfall, is highly unlikely to be infected by the disease because it is not able to complete its life-cycle and spread. The disease has never been noted in the Western Cape although it does occur in the Eastern Cape.
Modelling the influence of the climate on the development of the disease illustrates this situation in South Africa. There is some risk of the disease in the Eastern Cape in February, but there is no risk in the Western Cape at any time of the year.
The influence of climate on the risk of CBS disease development in South Africa during months when citrus fruit is susceptible to infection
(Manstrat CBS model, 2014).
Some years ago this argument was put to the European Food Safety Authority (EFSA) by the South African plant protection organisation. That is because all citrus in Europe is grown in the Mediterranean region, where there is no danger of CBS spreading to the EU. A model (CLIMEX) was used to predict CBS development in the European Union [5]. From these predictions, it was concluded that the climate of the EU citrus-growing areas was unsuitable for the establishment of CBS.
However, this was rejected by the EFSA, who claimed that the CLIMAX model had limitations and that the climatic conditions in the Eastern Cape, where CBS occurs, are similar to some areas where citrus is grown in the EU [5]. After all the intensive investigations and studies of the CBS disease by the South African authorities, this answer may seem unreasonable. However, it is likely that the EU authorities approached the problem very conservatively and with extreme caution. This is understandable. It must be remembered that the disease has never declined or disappeared anywhere in the world once it has become established.
These regulations are still in place, and the EU monitors levels of the disease through site inspections at pack houses in South Africa. Inspectors have noted 15 cases of CBS in 2015 which is less than in 2014 (28) or 2013 (35) [1].
References:
Urban areas in the world's developing countries are growing at an unprecedented rate. Over the next ten years, the number of city dwellers in Sub-Saharan Africa will grow by almost 45 percent from 320 to 460 million. That is, there will be an increase, every month, of over 1 million people living in the cities... Read more
Contributions from Dr John Lapham & Colleen Janse van Rensburg
Recent weeks has seen regular reporting on the severe drought conditions and accompanying heat that has South Africa in its grip with resulting water restrictions implemented in various cities across Gauteng. The University of North West estimates that North West province has lost up to R 1.5 billion as a result of the current drought. R 350 million was allocated for drought relief in KwaZulu-Natal at the beginning of 2015. The Free State Province is the latest province to be declared a disaster area with only 1% of farmers reporting their land suitable for crop production or grazing.
So, what is the true extent of the drought? Satellite Imagery can be used as a practical tool to monitor drought conditions. NDVI images describe vegetation activity and show the highest possible "greenness" values measured during a specific period. This relationship makes it possible to monitor stressed vegetation or agricultural drought conditions. Rainfall data cannot show the spatial extent of drought conditions, but remote sensing data, through NDVI's, help to map drought conditions.
Figure 1: Drought Severity Index for October 2015
Figure 1 show how low rainfall in October over KwaZulu-Natal has caused lower vegetation activity - indicated in orange and red - Figure 1. Below-normal vegetation activity is dominant in the Free State province - displayed in orange. The wheat production areas of the Western Cape only show a "drought signal" because of harvesting taking place.
Cumulative time series analysis further enhances the mapping of drought conditions. Data accumulated over a number of months, compared to the same period in history, can highlight the severity of drought conditions. The Percentage of Average Seasonal Greenness (PASG), figure 2, is an example of how long-term data can be used to monitor and map drought affected areas.
Figure 2: Percentage of Average Seasonal Greenness for the last 6 months ending in October 2015.
Drought is a long term phenomenon. Focussing on longer time-periods is a more reliable method to monitor and map drought. Lower vegetation activity due to low rainfall over South Africa during the last 6 months, can clearly be seen in the red and orange indicators - Figure 2. Only a small number of districts show normal vegetation activity (beige), or positive vegetation activity (green).
Figure 3: Current model predictions for Sea Surface Temperature in the Pacific – El Nino.
Periods of below normal rainfall in South Africa are usually linked with the El Nino event while above normal rainfall is usually linked to La Nina. The global climate is currently affected by one of the strongest El Nino events on record. Latest predictions issues by the Australian Bureau of Meteorology indicate El Nino conditions will continue until June 2016 (Figure 3). South Africa is likely to continue to receive below-normal rainfall as we've already experienced since the start of the summer rainfall season.
The current drought conditions are having an immediate effect on many annual crops planted at the beginning of the summer rains. The severity of the drought in the last month (up to the end of October, figure 1), in central and northern Free State and KZN means that planting of maize has been delayed and where planted, germination has been seriously affected. The area is where the bulk of the country's maize is grown. The longer term dry conditions since May (figure 2), have caused stress to many of the perennial crops. In KZN and Mpumalanga crops such as bananas, macadamias, citrus, avocadoes and others, have been affected (the exception is where plentiful irrigation water was available). With the current heat, the situation is deteriorating rapidly for these, and annual crops.
The effect on livestock is also pronounced. Not only do intensively farmed livestock such as poultry, pigs, dairies and feedlots rely on crops affected by the drought as their main feed sources, but livestock farmed extensively suffer as a result of the effects that prolonged drought has on natural veld. If the stocking rate is not adjusted according to veld conditions, there is a high possibility of overgrazing and overall deterioration of the veld. Apart from the removal of more favourable grasses and increasing the risk of soil erosion, species composition may change under continuous grazing pressure. The result is that vegetation growing in the area will not be of ta nutritional quality to sustain growing and productive animals. Feed will have to be supplemented while current drought conditions continue to limit feed sources. This in turn will result in higher input costs for producers and eventual higher food prices for all.
Urban areas in the world's developing countries are growing at an unprecedented rate. Over the next ten years, the number of city dwellers in Sub-Saharan Africa will grow by almost 45 percent from 320 to 460 million. That is, there will be an increase, every month, of over 1 million people living in the cities... Read more
Urban areas in the world's developing countries are growing at an unprecedented rate. Over the next ten years, the number of city dwellers in Sub-Saharan Africa will grow by almost 45 percent from 320 to 460 million. That is, there will be an increase, every month, of over 1 million people living in the cities. This increase in the urban population is driven not by only high birth rates but also by an influx of rural people into the cities. The main driving forces behind this are the desire to escape from hunger, poverty and insecurity in the rural areas despite facing a potentially and equally bleak future in the city.
Currently, 45% of the global population live in urban areas; by about 2022 this will exceed 50% and by 2050 two out of every three people will be living in cities. In low-income countries, this means cities with high levels of poverty, unemployment and food insecurity. Currently, 30% of the developing world's urban dwellers have no formal employment and live in crowded slums, without access to health, water or sanitation services. By 2020, this could be as high as 45%. The result is sprawling, degraded and impoverished cities.
However, cities have historically been centres of opportunity, especially for rural people seeking a better life; social diversity, economies of scale and support services presented resourceful individuals with opportunities for advancement. The difference is that these cities developed over centuries and the supporting structures developed and expanded with the population; today mega-cities develop over a few decades.
The challenge for governance is to plan strategies to mitigate the effects of this vast overcrowding. One option is the concept of greener cities because it offers the hope of sustainability through self-reliance, with greater social and economic stability. In cities of the developed world, greener-cities often imply high-tech urban agriculture, eco-architecture, waste-recycling, green areas and zero emissions. In cities of low-income countries, the concept and objectives are distinctly different. The priorities are food security and income-earning opportunities; for this to be sustainable, socio-economic conditions must be stable and the environment clean.
One activity well-suited to greener cities in developing countries is urban and peri-urban horticulture (UPH). UPH is the cultivation of vegetables, roots, tubers and fruit within the city and its surrounding areas (peri-urban). UPH is attained by using production systems such as market-gardens, simple hydroponic micro-gardens, small-scale greenhouses, growing-troughs and other means. The urban horticulture concept is not new but tried and tested in some cities - there is, however, an urgency to implement it widely now because of the exponential increase in city dwellers. China initiated a policy of including food production in urban development in the 1960's. Today more than half of Beijing's vegetables come from market gardens within the city avoiding the cost of transportation of vegetables from rural areas. The policy was introduced in Cuba in the 1990's and now 60% of the countries fresh produce originates from urban and peri-urban centres. Although not widely recognised, in some African cities up to 40% of people are engaged in some form of food production.
In any urban horticultural production system, design priority must be given to two issues - water supply (which must be constant) with its efficient use, and space. Space is obviously limited and must be used efficiently through technologies such as small-scale greenhouses and tunnels (which maximise production per unit area). Some examples of these simple technologies are described and shown below.
Small-scale greenhouses facilitate the production of higher yielding crops; the environment is protected, evapo-transpiration is reduced and if hermetically sealed, insects cannot enter. Plants are often watered using simple gravity-fed drip irrigation systems designed for market gardens.
Small-scale greenhouse
(Peri-urban area Maputo, Mozambique)
Growers sometimes prefer not to use small-scale drip systems. The reason for this is because of the arduous task of having to lift water to fill the water tank to provide a pressure-head for the drip system (if they do not have a pump). There are alternatives that facilitate easy watering. One option is a growing trough watered through a tube once every couple of days - adding water until it overflows through the outlet pipe. The water is stored at the base of the trough (as shown in the diagram below) and absorbed into the growing media through capillary action. Once the level is low, it is watered again. These troughs are more suited to small areas and can be used to grow vegetables next to the owner's dwelling. Furthermore, they can be easily fabricated to the correct dimensions and do not have to be bought.
Vegetable growing troughs incorporating a simple watering system
(See Extension Suite Online®, ESO)
In Africa strategies for greener cities are often in place, and some have been implemented. However, the lack of awareness of the importance of urban and peri-urban horticulture is hampering progress in some other situations.
References:
At the beginning of October, South Africans saw an intense heatwave cover much of the country reaching temperatures of over 40 °C in some areas. These temperatures were well in excess of the upper critical temperature of an animal's thermo neutral zone, putting them at an increased risk of... Read more
At the beginning of October, South Africans saw an intense heatwave cover much of the country reaching temperatures of over 40 °C in some areas. These temperatures were well in excess of the upper critical temperature of an animal's thermo neutral zone, putting them at an increased risk of suffering from heat stress. Heat stress has many negative consequences, and it is therefore important that farmers recognise the signs of heat stress and are prepared for it.
The thermo neutral zone is an animal's temperature tolerant range. It is the range of temperatures where animals maintain a stable core body temperature without having to use energy to warm up or stay cool. When temperatures (and humidity levels) rise above the upper critical temperature, animals will use extra energy by increasing their respiration and heart rates and begin panting and reduce their feed intake. When the animal's attempt to dissipate heat is unsuccessful or overwhelmed, heat stress occurs, and the performance and health of the animal declines.
Heat stress is driven by a combination of factors, most commonly temperature and humidity. It affects all types of livestock, and in different measures, and thus it is imperative that farmers be proactive with a management plan in place to address heat stress to avoid any losses. Since heat in summer cannot be avoided, farmers need to act when temperatures begin to rise, as sudden cooling methods of animals already in distress may have more disastrous consequences.
Some animals are more susceptible than others, and farmers should be on the lookout for early signs of distress.
Beef cattle
Dairy cattle
Sheep and goats
Pigs
Poultry
Animals most susceptible to heat stress include very young and older animals as well as pregnant and sick animals. Pigs are generally at a higher risk than other animals due to their lack of sweat glands and small lungs. Feedlot cattle are also at risk as they are physiologically overweight and have the least amount of lung capacity relative to their body weight. Animals with dark hides also have a higher core body temperature than animals with lighter coats.
All farmers can take steps during the summer months to maintain animal performance. Simple management procedures include providing animals with cool, clean water at all times and providing shade in paddocks. Adjusting feed rations by adding more dense feeds to the diet and switching to evening feeds rather than morning feeds to avoid peak digestive heat coinciding with peak day-time temperatures. Animals should only be handled and transported during cooler times of the day, and farmers should avoid overcrowded conditions.
Flies and biting insects must be controlled as they add to the stress, thus further compromising the animals' performance and health.
Since air movement is critical especially in housed animals as it promotes evaporative cooling, farmers can put up fans to promote this. Sprinkling systems help cool animals as well as the ground. However, avoid fine mist sprinklers as it can add to humidity levels and exasperate heat stress further.
While the summer heat cannot be avoided, farmers should be proactive and have a management plan in place to maintain animal performance and prevent losses from heat stress.
References
El Nino, La Nina, and The Southern Oscillation Index (SOI) form part of a climatic cycle called the El Nino Southern Oscillation (ENSO). ENSO describes the fluctuations in temperature between the ocean and the atmosphere in the east and central Pacific Ocean... Read more
SEl Nino, La Nina, and The Southern Oscillation Index (SOI) form part of a climatic cycle called the El Nino Southern Oscillation (ENSO). ENSO describes the fluctuations in temperature between the ocean and the atmosphere in the east and central Pacific Ocean.
El Nino and La Nina are opposites of one another. We refer to El Nino as the "warm phase", and to La Nina as the "cold phase" of the Pacific Ocean. During El Nino years, warmer waters shift eastwards towards the central Pacific. During La Nina years warmer water shift westwards towards the Australian coast causing the central Pacific Ocean to be much cooler. The shifting of cold and warmer water is an example of how the Pacific Ocean not only influences our local climate but also how it influences the global climate. The change in the ocean temperature causes disruptions in the normal wind circulation patterns causing changes in rainfall patterns globally.
SOI is the atmospheric element of El Nino. The Walker Circulation (Figure 1) describes the way tropical air moves between low and high-pressure regions in the tropical Pacific Ocean. During El Nino periods, the low pressure moves eastward towards the central Pacific together with the warming ocean while during La Nina periods it moves more westwards towards Australia resulting in changes in the global circulation patterns.
Figure 1 Visual representation of the air flow in the Pacific Ocean during neutral conditions, courtesy of NOAA (NOAA Climate.gov drawing by Fiona Martin)
SOI is calculated by comparing the air pressure differences between Tahiti and Darwin. Negative values below -7 usually indicate El Nino conditions, when the air pressure is below normal over Tahiti and above-normal over Darwin. Positive values above 7 usually indicate La Nina conditions with above-normal air pressure over Tahiti and below normal air pressure over Darwin.
Between 1950 and 2003, about 14 El Nino events affected the world's climate with the 1997/98 El Nino event being the most brutal although South Africa escaped the worst of it.
The current ENSO situation
The current (27 September 2015) SOI value of -18,1 indicated the presence of a strong El Nino event. Current climate predictions (Figure 2) by the Australian Bureau of Meteorology indicate the strengthening of El Nino conditions until the end of the year. Predictions further indicate that El Nino conditions should start to weaken from next year with the possibility of reaching neutral conditions by June 2016.
Figure 2 Current El Nino/La Nina predictions provided by the Australian Bureau of Meteorology.
ENSO and South Africa
Periods of below normal rainfall in South Africa are usually linked with the El Nino event while above normal rainfall is usually linked to La Nina. Only 30% of South Africa's rainfall variability can be attributed to ENSO events. South Africa has various climatic regions, and each region has its unique correlation with ENSO.
Recent El Nino events with relatively little impact on South Africa's rainfall occurred in 94/95, 97/98, 04/05 and 09/10 while severe impacts occurred in 82/83, 86/87, 91/92, 02/03, and 06/07. During the 87/88 El Nino South Africa received above normal rainfall.
Rainfall statistics for the last 10 El Nino events for December to March released by the USGS indicate that the Limpopo Province is the most vulnerable to El Nino, receiving below normal rainfall 5 times during the period. During the same time, the eastern region of Limpopo received below normal rainfall, between 6 to 8 times. The Northern Cape Province is another province that is affected, with the majority of the region receiving below normal rainfall at least 5 times, with small areas receiving below normal rainfall between 6 to 8 times. The remainder of South Africa was influenced by El Nino between 1 to 3 times the last 10 El Nino Events.
Conclusion
ENSO events have influenced South Africa's climate in the past. Its impact, however, is mainly limited to specific regions although all of South Africa has experienced below normal rainfall during El Nino at some point in the past. Areas most vulnerable to the effects of El Nino are Limpopo and the Northern Cape Provinces.
References:
Since 2002, the number of mobile-phone users in Sub-Saharan Africa has increased from about 16 million to over 650 million today. The rate of increase has been 41% annually and is second only to South East Asia. However, of more significance for Africa is the adoption of mobile money services by mobile-phone users. The service was initiated... Read more
Since 2002, the number of mobile-phone users in Sub-Saharan Africa has increased from about 16 million to over 650 million today. The rate of increase has been 41% annually and is second only to South East Asia. However, of more significance for Africa is the adoption of mobile money services by mobile-phone users. The service was initiated in 2007 with the introduction of m-Pesa in Kenya, and now there are 146 million registered mobile money users of which 62 million are active. This is more than anywhere else in the world, and the 62 million users constitute 60% of active users worldwide (this is shown graphically in the figure below).
How is this of importance to agriculture on the continent? Well, the agriculture sector accounts for one-third of the gross domestic product and 75% of employment in countries in Sub-Saharan Africa. This means many of the mobile-phone owners and mobile money users will be farmers who are nearly all smallholders. Although there is credible evidence of a positive impact from this technology to-date, how it will specifically develop in future is less well-defined. However, it does undoubtedly present some unique opportunities for those involved in the business. These opportunities are discussed and highlighted below.
If mobile phones are to be used to assist small-scale farmers, it is important to focus on their needs and adapt the IT applications appropriately. Broadly speaking small-scale farmers need better and more timely market information, timely and appropriate crop and disease management advice, production advice, stronger links to value chains (with geo-located information) and better access to finance. Potentially all these needs can be provided through mobile devices.
One farmer requirement that is being met is the farmers' need for access to financial services, substantiated by the burgeoning growth in mobile money services. It is a reflection of not only the needs of the rural people but also urban dwellers. At least 70% of all people in Africa are "unbanked" - that is, they do not have bank accounts, making, amongst other issues, micro-financing of small-scale farmers impossible to sustain. With mobile money, users do not need a formal bank account - the balance of money in mobile accounts is maintained by the mobile money service provider (that is, the mobile network operator, MNO).
In Kenya, it is estimated that of the mobile-phone owners 60% use mobile money, while, in Zimbabwe the figure is 45%. Many of the phone owners not using mobile money services are probably in the rural areas. Initially, the acquisition of mobile phones and mobile money services obviously started in urban centres but there is now strong competition among service providers for a share of the substantial rural market. Consequently, service providers are moving beyond the standard mobile-money services to provide products such as mobile insurance, mobile credit and mobile saving services specifically designed for farmers.
Providers are strengthening their internal capabilities and although domestic person-to-person transfers still dominated the business the fastest growth in 2014 occurred in bulk disbursements, bill and merchant payments. Farmer groups, such as out-grower schemes, are replacing inefficient cash payments to farmers with mobile money transfers. Examples that are well-suited to this are cocoa and tobacco out-grower schemes where farmer-groups can number over 100 000 - the majority of farmers within these schemes have proved willing to use the mobile-money system.
To attract users in the agricultural sector mobile money providers are also attaching non-financial applications to their service. Of particular interest and value to farmers are: weather forecasts; current market information and prices; value-chain information on suppliers and markets (specific to the user's location); pest and disease warnings; and information on best production practices. Products such as AgriSuite® provide all this in a contemporary, user-friendly format.
The proliferation of mobile money users on a continent where the majority of people are engaged in agricultural activities is leading to the convergence of the IT and agricultural sectors. This presents numerous opportunities to those involved in the businesses, as described above. However, the nature of IT development results in rapid change and future doors to further undefined and unexpected opportunities are likely to open.
Mobile-money users in 5 regions of the world - Sub-Saharan Africa shown in blue (GMSA: Mobile financial services for the unbanked; 2014)
References:
Temperature plays an important role in photosynthesis. Photosynthesis is a chemical process where sunlight changes carbon dioxide into sugars used by plant cells as energy. The photosynthesic process increases slowly from 5°C to an optimum when... Read more
Temperature
Temperature plays an important role in photosynthesis. Photosynthesis is a chemical process where sunlight changes carbon dioxide into sugars used by plant cells as energy. The photosynthesic process increases slowly from 5°C to an optimum when the leave temperature reaches 30-35°C above which the process starts to decrease. The plant growing season in South Africa is characterized in general, by optimum temperatures.
As latitude increases, temperatures decrease. Latitude in a way determines where tropical and subtropical crops can be grown while altitude on the other hand plays a role in the temperature. Although there is a 3 degree difference in latitude between Johannesburg and Bloemfontein, the 350m altitude difference causes the mean annual temperature to be the same.
Since a large part of South Africa's interior consists of a plateau and the great escarpment, this area tends to be cooler than other parts of the world with the same latitude simply because of the elevation. Temperatures in South Africa are further influenced by the cold Benguala current in the west and the warm Augulhas current in the east.
Humidity
Humidity is the extent of water vapor in the atmosphere, measured as a density of vapor pleasure. Relative humidity refers to the ratio of actual vapor pressure compared to saturated vapor pressure and is expressed as a percentage. The relative humidity is high along the warm eastern coastal regions of South Africa, and decreases significantly to the western parts of the country. High humidity reduces the rate of transpiration, reducing the water requirements of crops and increasing the rate of photosynthesis. While high humidity can be an advantage for some crops, it can however, lead to the development and spread of diseases in other crops.
Sunshine
Sunshine and radiation are important for plant growth and the more sunshine hours will generally lead to higher the crop yields and South Africa's abundance of sunshine makes it ideal for crop production.
Wind
Wind is defined as air moving from a high pressure area to a low pleasure area and the higher the difference in pressure, the stronger the wind. The temperature of wind can influence the temperature of an area and indirectly affect crop yields. Strong and warm winds can lead to the drying out of soil. Wind can cause damage to fruit crops and it affects the burning of veld while wind erosion remains a serious problem as it is a major cause of loss of topsoil in grazing and cropping systems.
A Geographic Information Systems (GIS) is a technology that is used to combine environmental features, with data about those features in data tables, to map and analyse the real world. Geographic indicates spatial data. Spatial data is referenced to a location on the earth... Read more
A Geographic Information Systems (GIS) is a technology that is used to combine environmental features, with data about those features in data tables, to map and analyse the real world. Geographic indicates spatial data. Spatial data is referenced to a location on the earth. The data attached to these spatial features are referred to as attribute data. An example of this would be the Abattoir data in AgriSuite. The actual location of the Abattoirs is the spatial data. Additional data such as the name, address and contact information would make up the attribute data. It is the combination of spatial, and attribute-data that makes a GIS a powerful problem-solving tool.
The most basic form of GIS is mainly used for mapping purposes. The real power of GIS lies in the spatial and statistical analysis of geographic information. The result of this analysis can provide useful derived information. An example is the crop suitability information available for each farm within the AgriSuite system. The crop suitability information was derived by combining various data layers such as soil, rainfall, temperatures and many other climate variables to determine areas suitable for specific crops.
While GIS refers to the use of data layers and geographic data to produce maps through spatial analysis, the term Geospatial mainly refers to the technologies and applications of geographic data. For example, when a user logs into AgriSuite and selects Agricultural Weather or Agricultural Infrastructure, the geospatial application gathers the required information from the user to display their current location on the displayed map.
GIS as described by United States Geological Survey (USGS), Environmental Systems Research Institute (ESRI) and National Aeronautics and Space Administration (NASA):
United States Geological Survey (USGS):
"In the strictest sense, a GIS is a computer system capable of assembling, storing, manipulating, and displaying geographically referenced information, i.e. data identified according to their locations. Practitioners also regard the total GIS as including operating personnel and the data that go into the system."
Environmental Systems Research Institute (ESRI):
"A geographic information system (GIS) is a computer-based tool for mapping and analysing things that exist and events that happen on earth. GIS technology integrates common database operations such as query and statistical analysis with the unique visualization and geographic analysis benefits offered by maps."
National Aeronautics and Space Administration (NASA):
"GIS is an integrated system of computer hardware, software, and trained personnel linking topographic, demographic, utility, facility, image and other resource data that is geographically referenced."
A GIS system can be broken down into four elements. These elements are:
The distinct features of drip irrigation systems are that they save on the use of water and labour while still enabling the farmer to produce yields equivalent or better than other irrigation systems. For the small-scale farmer, with access to limited amounts of water and dependant on his own labour, this would seem attractive. However when modern-day drip irrigation technology... Read more
The distinct features of drip irrigation systems are that they save on the use of water and labour while still enabling the farmer to produce yields equivalent or better than other irrigation systems. For the small-scale farmer, with access to limited amounts of water and dependant on his own labour, this would seem attractive. However when modern-day drip irrigation technology developed some decades ago, with the introduction of in-line drippers and associated sophisticated equipment, the systems were expensive and capital intensive. Although this was obviously not suited to small-scale farming, these advances did provide the basis for the subsequent designing of small-scale, low-cost systems, designed for small areas, from 100 to 2 000 m2. Often known as family drip systems, and perfectly suited to the irrigation of vegetable gardens. The drip systems are gravity-fed so do not require power, are based on low-volume drip technology and are not expensive. Superficially they seem ideally suited to the small-scale farming sector.
Consequently for the last decade or two their use by small-scale farmers has been promoted by development agencies and marketed by the private sector. Despite the advantages of the drip system and vigorous attempts at promotion, the adoption of drip irrigation by farmers in Africa has been minimal. In fact, less than 5% of the arable land in Africa is irrigated at all, and only a small fraction of this (< 1%) is under drip irrigation. Within this small fraction, the adoption of small-scale drip systems has not fared well at all. Studies show that in Kenya, 78% of small-scale drip irrigation projects were abandoned within two years [ref. 3, 2005] and in Zimbabwe, 63% of farmers abandoned their schemes within the same period [ref.1, 2007].
There are numerous reasons suggested for this, but it often seems that the operation and maintenance of the system are not all that easy for many farmers (despite claims to the contrary by those promoting it). Significant among these are difficulties with the supply of water, its storage and use. Because the system is gravity fed, water must be lifted into a tank over one metre high to provide the necessary pressure head. This is a tedious and arduous exercise - to apply 5mm of irrigation per day onto 500 m2 of a crop - 2.5 tons of water needs to be lifted daily. However, this can be facilitated by another piece of appropriate technology, the treadle pump. The adoption of small-scale drip irrigation systems would probably be significantly more successful if each project included a treadle pump.
Other difficulties farmers faced with the maintenance of the system, included blockages, wear and tear of the drip lines, filtering problems and damage to equipment by rodents and other animals [ref. 2]. However in any survey it is difficult to quantify the influence of farmers’ personal preferences, diligence, operational errors and personality. The farmers selected by the promoters of the system will depend on the objectives or motives of the promoters. Often development agencies select farmers that appear the most needy hoping appropriate technology will mitigate their problems; often these farmers are the least likely to succeed. Subsequently the private sector often becomes involved because it is in their interests to implement successful schemes; furthermore they have the technical expertise and backup for farmers.
Despite their involvement, there has not been any great burgeoning of small-scale drip schemes in African countries. However this situation requires more optimistic qualification - and that is the fact that there have been a number of success stories. In Kenya low-cost, small-scale drip irrigation systems generated 2.8 times the yield of field-grown tomatoes while using only 45% of the water traditionally applied by hand. In Sudan drip irrigation saved irrigation water by 60% and increased the yield of onions by 40% compared to surface irrigation [ref. 4]. Sustained success, such as this, generates interest amongst neighbours resulting in their adoption of the technology. Well-focused and well-planned programmes, such as these, will provide a centre-point of interest from which adoption of new technologies can then spread. This strategy has proved successful in the past and must be noted in future developments.
Winter is over as we move into September. New leaves and blossoms are starting to appear on shrubs and trees as many farmers look forward to the spring rains and an end to the dry soil of winter. Signs of greenery and grass re-growth are a welcome sight after the cold and... Read more
Winter is over as we move into September. New leaves and blossoms are starting to appear on shrubs and trees as many farmers look forward to the spring rains and an end to the dry soil of winter. Signs of greenery and grass re-growth are a welcome sight after the cold and dry season. However, it is also the growth period for unwanted plants like weeds and poisonous plants.
Poisonous plants are often among the first green plants seen after a dry spell and once consumed, are dangerous to the well-being of animals, often causing a drop in animal performance and even death. In South Africa, there are approximately 600 species of indigenous poisonous plants. Poisonous plants develop seasonally and appear in specific regions of the country.
Despite goats, sheep and cattle being mostly selective grazers, they are vulnerable to poisonous plants during food shortages as a result of water scarcity and poor management factors. Many factors cause increases in the toxicity of plants or promote their growth. These factors include sudden changes in temperatures, dry weather conditions leading to drought, toxic soils (alkaline and acidic soil) from fertilizer use, and poor pasture management. Mould contamination of feeds and hay also leads to plant poisonings in livestock.
It is preferable to have poisonous plants eradicated from the grazing areas to avoid fatalities, since apart from supportive treatment, there is little else farmers can do for their animals once the plant has been consumed. However eradicating these plants is not always possible and farmers should apply preventive measures to reduce exposure to poisonous plants of their animals.
Care should be taken when letting animals out to graze to prevent the development of poisonous plants in grazing areas. Proper grazing procedures will help to prevent overgrazing and the development of dry open grounds. Farmers should also, not let their animals graze areas where a veld fire had recently occurred. Since newly purchased animals are more in danger of being poisoned as they are not familiar with the area, new animals should be introduced to the veld over a period. This introduction period will allow the microbes in the rumen to adjust to the change of vegetation and will limit animal exposure to poisonous plants.
AgriSuite Online® offers comprehensive information about livestock poisonous plants under the Animal Production menu item. Users can view a list of the most prominent poisonous plants in South Africa and the effects they have on animals. Veld and pasture management information that farmers can use to prevent the development of poisonous plants is also available. Should a farmer not be familiar with some symptoms animals are showing and needs to call someone for assistance, contact details of close veterinarians in the area are available under the Agricultural Infrastructure menu item.
Animals that consume poisonous plants may die or take a long time to recover. This will put a strain on farmers that need to care for unproductive animals. By using AgriSuite Online® to help identify poisonous plants and learn how to prevent livestock consuming them, farmers will save on medication costs and enjoy the returns from more productive animals.
Uncontrolled veld fires can be devastating, causing great losses in livelihood, livestock, crops and infrastructure. Fact is that they are a natural phenomenon, and occur annually in especially grasslands, woodlands, fynbos, and in indigenous forests in South Africa. Veld fires offer important... Read more
Uncontrolled veld fires can be devastating, causing great losses in livelihood, livestock, crops and infrastructure. Fact is that they are a natural phenomenon, and occur annually in especially grasslands, woodlands, fynbos, and in indigenous forests in South Africa. Veld fires offer important benefits to the ecosystem and biodiversity protection.
There are two fire seasons in South Africa, namely the dry winter season in the summer rainfall regions, and the dry summer season in the Cape winter rainfall region. Fires require oxygen, heat and fuel to get started and these conditions are perfect in the dry seasons when it is hot, grass is long and dry and wind is moderate to strong. Farmers need to prepare well in advance for the fire season and should be aware of any early fire warnings in their area.
Veld fires always start small, but their rate of spread and intensity depends on the weather and wind conditions, the terrain and the amount and condition of available fuel (dry plant material). About 10 % of fires occur through natural occurrences such as lightning, while 90 % are started by humans for a number of reasons, often due to careless behaviour. Since fires can spread very rapidly, especially when conditions are rife, farmers should always have available plans in place in the event of fires occurring.
All landowners are obliged to develop firebreaks and should be prepared and equipped to fight fires and prevent their spread as stipulated by the National Veld and Forest Fire Act, 1998 (Act No.101 of 1998). Chapter 2 of the act regulates the establishment, registration, duties and functioning of fire protection associations (FPAs), whereby farmers should work together playing an active role in managing and planning fire management and taking co-ownership of the risk management process.
Sadly some fires are extremely intense and get out of control, destroying large areas and causing devastating losses. Apart from the direct and immediate loss experienced, it takes time for the land to recover. Livestock that survive the initial fire often die of the after effects from burns and smoke inhalation several days or weeks after, while others face severe food shortages.
AgriSuite Online® serves as a useful tool for farmers by providing them with an early warning fire alert in their area, based on weather conditions. It is always important for farmers to be on high alert for possible fires and to ensure that their fire fighting equipment is in good working order. The early warnings on AgriSuite® are updated daily thus helping farmers to prepare well in advance. Radios and cell phones should be kept charged and livestock moved out of grazing land to open bare land or ploughed fields for safety when fires are imminent.
Should a fire be unavoidable, farmers will need to assess their animals after the fire has passed and treat all those affected. Animals severely injured from the flames or from smoke inhalation should be humanely euthanized. Furthermore farmers should try to preserve their land resources as much as possible in order to ensure the recovery of the veld and reduce soil erosion. Livestock numbers may need to be reduced or only productive stock kept while others are fattened in a feedlot.
Avoiding grazing of the veld when burnt grasses show re-growth will help with veld recovery. While it is ideal to allow the grasses to be rested for two full seasons, this is not always possible. Following an effective veld management system and planning for the annual fire season goes a long way to preserving the natural veld and keeping livestock safe.
Farmers can log onto AgriSuite Online® to find more information regarding the Veld and pasture and to view possible fire warnings in their area.
South Africa is located within a subtropical belt of high pressure causing sunny skies and reduced precipitation. For this reason, South Africa is rated number 27th of the driest countries in the world, with a mean annual... Read more
South Africa is located within a subtropical belt of high pressure causing sunny skies and reduced precipitation. For this reason, South Africa is rated number 27th of the driest countries in the world, with a mean annual precipitation of 500mm, compared to the global average of 850mm.
Atmospheric pressure is affected by temperature and altitude. Warm air causes low pressure while cold air causes high-pressure systems.
The following air currents affect the climate of South Africa:
Two important ocean currents influence South Africa's climate. The warm Agulhas current, with a temperature of around 20 °C, originates at the Equator and flows south along the east coast of Africa. This current is a fast moving one and due to the high temperatures, evaporation is fast, causing precipitation.
The Benguela current originates in the Antarctic and flows north along the west coast of Africa. This current is a slow moving one with temperatures between 9 and 12 °C. The Benguela current supports an abundance of fish species and is very lucrative to the fishing industry. However, because of the low temperatures, very little evaporation takes place and this result in very little rainfall along the west coast.
South Africa lies between the 22° and 35° south latitudes. One degree of latitude equals 100 km. Temperature is affected by latitude. Annual temperatures decrease as the latitude increases and the effect of this aspect also becomes more pronounced. If all conditions were similar, the temperature would change by 0.4 to 0.6 °C for every one degree change, in latitude.
Altitude in South Africa varies from sea level to 3,400 m above sea level. For every 100 meter decrease in altitude, temperature increases by 0.5°C. If conditions are considered to be equal, Cape Town will have a mean annual temperature of 15.9°C while Table Mountain will have a mean annual temperature of 12.1°C. The reason for this lies in the difference of 760 meters in altitude.
For topographical purposes, South Africa consists of three areas:
The plateau ranges in elevation from 3400 meters in Lesotho, to 600 meters in the Kalahari. The Highveld is the main plateau in general terms, and here the altitude varies between 1,200 to 1,800 meters above sea level.
The coastal belt lies between the escarpment and the coastline. This area varies in width from 60 to 80 km in the west to 80 to 240 km in the south and east of South Africa. Aspect (the compass direction that a slope faces), has a major influence on temperatures. North-facing and western slopes are always warmer than eastern and south-facing slopes.
Much research has been done in the past on ultra-low-volume (ULV) application of pesticides. There are numerous apparent advantages to these application techniques for most farmers and superficially it appears especially well-suited to small-scale growers. However... Read more
Much research has been done in the past on ultra-low-volume (ULV) application of pesticides. There are numerous apparent advantages to these application techniques for most farmers and superficially it appears especially well-suited to small-scale growers. However, the adoption of this technology has not been as widespread as anticipated or hoped.
The rationale for advocating the application of lower volumes of pesticide is based on the need, to improve conventional spraying methods. Conventionally chemicals are mixed in large volumes of water and sprayed under high pressure, through nozzles, onto the crop. The weaknesses of this method are that it takes a substantial volume of liquid to work well and the resulting droplets vary greatly in size, from 6 to 700 microns in diameter. Volumes of water chemical mix can be from 800 to over 2 000 l/ha.
The very small droplets evaporate and the chemical is lost, or they drift away and not deposited on the crop. Furthermore, the very small droplets are easily inhaled by the operator. The very large droplets impact on the crop leaf, break up and much of the liquid splashes off onto the soil.
Spraying through the conventional nozzle is shown graphically below together with the resultant distribution of droplets on leaf surfaces.
To improve the uniformity of droplet cover on leaves, they developed a rotary atomiser. The atomiser is based on a spinning disc that disperses the chemical water mix (as shown below). The droplet size is very uniform. This method of spraying is often referred to as "controlled droplet application" while the spray applicator is referred to as a "rotary atomiser", "spinning disc" or "ULV applicator". Less than 50 l/ha of the chemical mix is applied by this method.
The advantages of using this method are numerous including the application of much less water and consequently the operation is less arduous when spraying manually. Another advantage is that there is much less drift of very small droplets or run-off of large droplets, thus using fewer chemicals, lowering the costs. Lastly, there is much less environmental contamination and the absence of very small droplets means operators are less likely to inhale spray, making it safer.
These attributes make the technique seemingly more suited to the average small-scale users, but at the same time the technology involved is difficult for them to adopt. The ULV-applicator is not readily available in remote areas and could prove costly for an individual farmer to own. It is also battery operated that may pose problems with charging or replacement and many of the pesticides used have specialised formulations that are not easily available. Also, the drift of droplets (from 30 to 100 microns) in windy conditions is more likely on small fields (adjacent crops can easily be affected). All these issues make it technology difficult for the average small-scale farmer to use.
However, ultra-low volume application does have a niche as is well suited when applied over large areas in a short time when a rapid response is needed. As a consequence, it plays a well-established role as the standard method of locust control and has been used similarly in aerial spraying campaigns against insect vectors, such as the tsetse fly. ULV ground application equipment enables the treatment of large crop areas manually (drift onto adjoining crops is less likely on large areas). Examples are the treatment with ULV pesticides of large areas of cotton in the Sudan Gezira, East and West Africa. Other developments such as fan-assisted ULV sprayers are used with success in greenhouses where droplets can be contained.
However, ULV technology currently finds itself overshadowed by other crop technologies that avoid the use of pesticides, removing the focus from ULV application. Despite this, it is a technology that mitigates many of the adverse effects of pesticides, saves the farmer money and has a place in crop protection.
References
We can describe Geographical Information Systems (GIS) as a modern expansion of conventional cartography. While both consist of a base map onto which we add supplementary data, they differ as there are no restrictions on the amount of additional data... Read more
We can describe Geographical Information Systems (GIS) as a modern expansion of conventional cartography. While both consist of a base map onto which we add supplementary data, they differ as there are no restrictions on the amount of additional data that we can add to a GIS map. GIS use analysis and statistics to support maps while cartographic maps are much more simplified and limited to the quantity of data that can be displayed.
The development of GIS between 1960 and 1990 is grouped into four phases. The first phase was dominated by a select number of individuals who would shape and direct the future research and development of GIS. The second phase saw GIS technologies being used by various national agencies throughout the world, leading to the development of best practices within the industry. In phase three GIS moved into the commercial marked while the last phase focus shifted towards making GIS more usable and user-friendly.
A number institutions played major roles in the development of the GIS we know it today. The most prominent amongst them were The Harvard Laboratory for Computer Graphics; the Canada Geographical Information System the Environmental Systems Research Institute (ESRI); and the Experimental Cartography Unit in the UK. With the shift in focus to the commercial use of GIS and the accessibility of Satellite Imagery, the development of new applications helped ESRI to become the dominant force in the industry.
Picquet created a map in 1832 to show the spread of cholera in the 48 districts of Paris by using colour gradients. This was the first documented use of maps classified as a GIS application. In 1854, Snow did the same for a cholera outbreak in London. Early in the 20th century a printing technique known as photozincography was used to separate layers from a map. These layers were all printed as individual themes, but it was still not a real GIS system as there were no analyses of the mapped data.
In the 1960's, GIS technologies were used to collect, store and analyse data about land-usage in Canada. This system was enhanced during the next thirty years and by the mid-1990's was driven by a mainframe computer and contained datasets for the entire Canada.
Harvard and ESRI developed enhanced ways to handle spatial data during the 1970 to 1980 periods. In 1990, ArcView was released as a desktop solution for map production. Many governments and the private sector used ArcView, and it soon became the industry’s standard software.
As the technology became more and more affordable over time, the use of it filtered down to the lower levels of government and smaller companies. With developments in internet technology, data sharing between governments and organisations throughout the world further enhanced the access and usability of GIS systems.
Not all GIS data are freely available, and the debate about ownership of data is still ongoing. While government institutions throughout the world remain committed to share data, commercial organisations remain reluctant to share data because of the commercial advantages involved.
A timeline of major events in GIS history can is available at www.gislounge.com/gis-timeline/
Biomes can be defined as areas with specific climatic conditions to which vegetation communities adapt. A biome therefore is a large area of land that is characterized by uniformity in the general vegetation. South Africa is divided into seven biomes. In the Land... Read more
Biomes can be defined as areas with specific climatic conditions to which vegetation communities adapt. A biome therefore is a large area of land that is characterized by uniformity in the general vegetation.
South Africa is divided into seven biomes. In the Land Cover section of AgriSuite Online® users are provided with a simplified layer map showing the location of the various biomes in South Africa. There are different ways to classify biomes. The elements usually taken into account include climate, habitat, animal and plant adaptation, biodiversity and human activity. Human activity is determined by climate, and since biomes are closely related to climate, they provide natural boundaries for human activity.
The vegetation consists of trees that form an uninterrupted canopy of leaves. These areas have a high annual rainfall, between 600 to 800mm and frost is absent. This is the smallest biome in land area in South Africa.
This biome is mainly found in the valley systems in KwaZulu-Natal and the Eastern Cape. Rainfall varies from 500 to 900mm per year. The valley system is relatively open in the northern regions, but moving towards the south it becomes very dense. A deterioration of grass species and increase of bush density is often caused by overgrazing and bad land management.
This vegetation type is commonly referred to as the bushveld and consists of grasses and trees. The canopy cover of this vegetation type varies from being open to a relative closed canopy. This vegetation type is found in the summer rainfall region with an annual rainfall of 200mm and more. This vegetation type is mainly used for grazing and browsing by livestock and game.
Grasses are the dominant vegetation type. This biome is located in the summer rainfall region and receives between 400mm to 2000mm. Frost is a common occurrence in winter. With good management practices, the carrying capacity of this biome remains very high.
The mean annual rainfall in this biome varies between 100mm and 500mm and the vegetation mainly consists of grass and shrub veld. Frost occurs frequently in the winter months. These areas are suitable for the grazing of smaller animals, mainly goats and sheep.
The mean annual rainfall in this Biome is between 20mm to 350mm per year. The rainfall mainly occurs in the winter months and the vegetation consists of succulent plants. Although the biodiversity is extremely high, the grazing capacity is very low and mainly goats and sheep are found in these areas.
The rainfall in this biome differs from 200mm to 3,000mm. The vegetation mainly consists of fine leaved species. Frost in these areas is very low. Despite its very high biodiversity, the grazing capacity of this biome is very low.
Tuta absoluta is commonly known as the tomato leaf miner or South American tomato moth. It is a member of the order Lepidoptera which includes moths and butterflies. The moth has a high reproductive rate... Read more
Tuta absoluta is commonly known as the tomato leaf miner or South American tomato moth. It is a member of the order Lepidoptera which includes moths and butterflies.
The moth has a high reproductive rate completing its life-cycle in 30 to 35 days with 10 to 12 generations per year; each female lays 250 to 300 eggs in her life-time. The larvae cause the damage on tomato plants by boring into leaves, fruit and other plant parts. They then feed from within the plant tissue causing a "mining" appearance, on the leaves in particular. Controlling the pest with pesticide sprays is difficult because the larvae are within the leaves. Many other solanaceous plants, such as potatoes, eggplants, sweet peppers and paprika, are infested by this pest. Tomato plants are attacked at all stages of growth, from seedlings to mature plants; damage is done to the apical buds, leaves, stems, flowers, and fruit. Infestations of tomato leaf miner in tomato can be devastating and may result in losses of 50 to 100% of the crop.
Tomato leaf miner was first noted as a pest in South America in the 80s and then appeared in some Mediterranean countries in 2006. It has since spread to North Africa, Sudan and East Africa. In the last few months the pest has left many crops devastated across tomato producing states in Nigeria, West Africa. Tomato farms in the Kadawa Irrigation valley and farms supplying Dangote's Dansa Tomato Company (processing factory) have been severely affected. This has resulted in prices of tomatoes on the biggest fresh produce market (Mile 12, Lagos) rising by over 100% when compared with the same period last year.
Scientist, Dr Arne Witt from CABI, has commented that: "This Invasive Alien Species is rapidly moving down the African continent, having already decimated crops in Egypt, Ethiopia, Kenya and northern Tanzania. Growers are at their wits end as to how best they can control this pest and many have abandoned tomato growing altogether. The race is on to prevent its spread further south with various interventions planned to mitigate its impact in areas where it is already present."
It has not been seen in Southern Africa yet. Awareness is the first step in slowing the spread of the pest. Together with this, identification of the pest is important. Adult moths are grey-brown; approximately 6 mm in size and have a wing-span of 10 mm. Males are somewhat darker than females. The adult is shown below together with damage caused by the larvae (caterpillars) on tomato leaves and fruit.
Newly hatched caterpillars are small (0.5 mm) in size and yellowish. When maturing, caterpillars turn yellow-green and a black band develops behind the head. Fully-grown caterpillars measure approximately 9 mm with a pinkish colour on their back. Pupae are light brown and approximately 6 mm.
As mentioned earlier, control is difficult because pesticides must be systemic and be able to penetrate through the leaf before they come in contact with the caterpillar. Furthermore, the fast development and short life-cycle of the pest has enabled some populations of the pest to develop resistance to organophophate and pyrethroid pesticides. Compounds such as spinosad, imidacloprid and Bt (Bacillus thuringiensis) have demonstrated some effect in controlling European outbreaks of the TLM moth.
If there are suspicious looking symptoms on tomato or potato leaves or tomato fruit, please contact the people below, at DAFF.
For media enquires please contact:
Ms Makenosi Maroo
Chief Director: Stakeholder Relations and Communications
Tel.: (012) 319 6787
Cell: 072 475 2956
E-mail: MakenosiM@daff.gov.za
For technical information please contact:
Mr Jan Hendrik Venter,
Manager: Early Warning System
Tel.: (012) 319 6384/ 6138
E-mail: JanHendrikV@daff.gov.za
References:
The history of mapmaking can be traced back more than 5,000 years ago. Humans have known and accepted the significance and value of maps a long time ago. Early maps were primarily designed to record the location of places of interest but were often also used to study the... Read more
The history of mapmaking can be traced back more than 5,000 years ago. Humans have known and accepted the significance and value of maps a long time ago. Early maps were primarily designed to record the location of places of interest but were often also used to study the geography of an area.
Historically, maps were radically different from modern day maps and early maps focussed on smaller areas such as cities, trade routes or hunting grounds. These maps were pictographic in nature - they were able to show only the features that those cartographers wanted to record. Rules for map making were non-existent, as older maps, for instance, did not have the same orientation we have today - North at the top of the map. The connection between the real world and the map were often not all that accurate while the centre of a map would often have more detail than towards to the edges of the maps. Because they were hand-made, early maps were often seen more as works of art more than anything else, and it was therefore also extremely expensive to produce. Due to the cost, these maps were often seen as a status symbol.
The Greeks and Romans continued to improve the process of mapmaking. Ptolemy, a geographer, mathematician and astronomer, lived in Roman Egypt around 150 AD. He published a scientific article titled "Geography" containing maps of various parts of the world with latitude and longitude lines. His system revolutionised geographical thinking by using mathematical rules to generate maps, and his work was used well into the 1500's by many scholars and geographers.
During the Middle Ages, there was little development in mapmaking in Europe and maps, often produced in monasteries, were mainly used for decorative purposes. In the Islamic world, on the other hand, mapmaking and geography, continued to develop. Al-Idrisi produced the first world map and wrote various books on geography.
Major changes occurred during the Renaissance era and particularly with the development of the printing press, map production no longer remained the domain of the monasteries. As publishing houses grew, maps became accessible to more people and not just the wealthy, while the establishment of learning institutions around 1600, encouraged scientific research, including the improvement of mapping and navigation. This led to a much better understanding of geography and mapmaking.
Maps produced during this era were in "black and white" only and included coastlines, country borders, mountains, rivers and place names. In some instances, maps were hand painted to add colour to the final product. In the 1700's the first themed maps were produced. These were often used to indicate the spread of diseases or to show the areas affected by flooding.
Maps have become more complex and accurate throughout the years as scholar's understanding of the earth, mathematics and geography expanded.
Today we produce maps with the assistance of satellite systems and surveying techniques. Modern day maps and techniques are extremely accurate and detailed, compared to those when mapmaking first started. Modern day maps have become critical in most fields of human enterprise.
Reference: Fundamentals of mapping (http://www.icsm.gov.au/mapping/history.html)
Livestock has always played an integral role in the agricultural sector in South Africa as an important source of animal protein in our diets, and will continue to do so in the future. With natural resources becoming constrained and limited, it is important for farmers to look at... Read more
Livestock has always played an integral role in the agricultural sector in South Africa as an important source of animal protein in our diets, and will continue to do so in the future. With natural resources becoming constrained and limited, it is important for farmers to look at sustainable agricultural practices to help promote farming methods that are profitable and environmentally feasible. In this article we will be looking at how farming with indigenous animals helps towards the promotion of sustainable agriculture.
With an increase in population numbers and the resultant changes in the market, many exotic livestock breeds have entered into our farming system. Exotic European breeds grow fast, produce high yields and are a well known feature of many commercial farms. Indigenous livestock however have remained an important source of food security for many small-scale and subsistence farmers. While these breeds may be smaller in size, and grow slower, they are much better adapted to South African conditions.
South Africa is classified as an arid country with hot, dry conditions prevailing throughout most of the year. Indigenous breeds are known to be more heat tolerant than exotic breeds and show more resistance to many of the diseases and parasites found in South Africa. They are well able to maintain their weight and condition despite relatively poor feed resources and manage to reproduce under less favourable conditions. While the production potential of the indigenous breeds may be lower than that of exotic breeds under more favourable conditions, the indigenous breeds outperform the exotic breeds during stressful periods like drought with severely restricted water and limited available feed resources.
Indigenous breeds have many features that help them to adapt to the dry conditions of South Africa. The fat tails of several indigenous sheep are a well known feature as are the humps seen in the Zebu and Sanga cattle. The fat stored in these appendages act as reserves that the animal can draw on during times when food and water is scarce.
Due to the hardiness of indigenous animals and their ability to survive under harsh environmental conditions, they do not require a lot of intense managerial inputs. Under stressful conditions, many exotic breeds are not able to perform to their optimum and are more prone to heat stress and diseases. In order to produce at their optimum, farmers of exotic breeds may need to adjust feed rations or put up additional shelters and cooling systems. The additional costs add up and put a strain on small-scale and subsistent farmers, further adding to their struggle for sustainability.
South Africa is home to a number of indigenous livestock breeds from cattle, sheep and goats down to ostriches, chickens and pigs. Some of these breeds come from traditional herds that have faced natural selection and have adapted over the years, while a few synthetic breeds have been developed here and are even experiencing success in other countries as well.
Log onto AgriSuite Online® to find out more about South Africa's indigenous breeds of livestock and how they can help towards promoting sustainable agriculture in South Africa.
Remote sensing has become a large part of our lives. We are confronted daily with remote sensing technologies without even realising it. Remote Sensing refers to the science or techniques of capturing information at a distance with specialised instruments without ever being in direct contact with the ... Read more
Remote sensing has become a large part of our lives. We are confronted daily with remote sensing technologies without even realising it. Remote Sensing refers to the science or techniques of capturing information at a distance with specialised instruments without ever being in direct contact with the object being captured or measured. The moment someone uses their cell phone to take a photo, they are in fact performing remote sensing.
Remote Sensing began nearly 150 years ago with the invention of the camera. The first photographs focussed on stills taken on the ground, but in the 1840's pictures were taken from tethered balloons for the purpose of topographical mapping. Around 1880 cameras were attached to kites to obtain aerial photographs. During the same period, smaller cameras were developed and mounted on carrier pigeons. At the turn of the century in early 1900, the focus shifted to the development of systems for military use. Rocket camera systems were developed that shot a camera into the sky. A parachute would deploy the moment the camera started to fall back to earth and that was the moment when the taking of photographs started. During World War I, the first photographs of the earth's surface were taken from aeroplanes.
The term "Remote Sensing" was first used in 1950 and references made to the measurements of objects from a distance. Scientist discovered how to measure radiation of different wavelengths and how they were reflected or absorbed by objects on Earth.
With man going into space around 1960, the first ever photographs of earth from space were captured.
Tiros1 was the first ever satellite launched in 1960 by NASA to observe the earth's weather patterns. This lead to the development and launch of ESSA 1 & 2 in 1966 and that gave the US the first global weather satellite system.
The Corona programme is an example of the first remote sensing satellites being developed for military purposes. These were crude systems and although they provided valuable information, the simple way of retrieving data resulted in data often getting lost. The satellites released film canisters towards earth that were captured by specialised aircraft, in midair.
In 1965, the USGS (United States Geological Survey) first mentioned the idea of using satellites to gather information about the earth's natural resources. In 1972, the first Landsat Satellite was launched to study and monitor the earth's surface.
Today, the earth surface is under constant surveillance from various types of satellites. Specific satellite systems are being developed for the specific needs of users capturing a wide variety of information used for research and decision-making purposes. Research and development are continually taking place to develop better methods to measure and capture information of the earth's surface. From humble beginnings, the science of remote sensing has evolved a great deal over the last 150 years.
A cultivar, or plant variety, is a grouping of identical plants selected for their desirable characteristics. After propagation, the seed is sold commercially to farmers to produce food or other products. The term "cultivar" is an abbreviation of "cultivated variety". A variety is... Read more
A cultivar, or plant variety, is a grouping of identical plants selected for their desirable characteristics. After propagation, the seed is sold commercially to farmers to produce food or other products. The term "cultivar" is an abbreviation of "cultivated variety". A variety is distinct from other plants or varieties within the crop species, and taxonomically forms a single botanical group of the lowest rank. We distinguish it from any other plant groupings of the crop, by its unique genotype.
Varieties are most often bred by research institutions or commercial seed companies with the aim of improving some characteristics. Reasons may range from improved yield, resistance to disease and pests, climate tolerance, to drought resistance, etc.
Over recent years, it has become apparent that there is an increasing need for crops that can thrive in hot, dry conditions. The changes in weather conditions are a result of "climate-change" which is now an accepted concept and an on-going long-term threat in southern Africa. Of immediate concern for the 2015-16 season are the shorter-term effects of the apparent development of El Nino conditions; this will significantly increase the risk of drought in southern Africa during the coming season.
These predictions highlight the need for tougher and drought-hardy crops. In southern Africa, severe drought can reduce maize yields by as much as 25% and has focused maize breeding efforts on achieving greater drought tolerance in the species. The "Drought Tolerant Maize for Africa Project" conducted by CIMMYT and IITA has developed 153 new varieties since its launch in 2006.
Drought tolerance in maize is a complex genetic trait regulated by many genes in specific sequences and at different locations on the DNA strands within the chromosomes. For this reason, most advances in breeding of drought tolerance in maize have been made by conventional methods (and less so by transgenic methods or genetic engineering).
Maize is most sensitive to water stress during flowering. In standard maize varieties, the silks originating from the kernels often dry out and die in drought conditions, before they are pollinated. This results in cobs with missing kernels (pips) and consequently reduced yields (see below). One of the main characteristics of drought tolerant maize is that the period between the tassels shedding the pollen and the silks emerging from the ears (cobs) is greatly reduced. Thus pollination most often takes place before silks have a chance to dry out and die.
Maize cobs affected by drought
Drought tolerant varieties also take up less water from the soils during their early growth stages. This means at flowering and pollination, more water is available in the soil to maintain the silks and also to enable kernels to fill out after pollination. Furthermore, the growth rates of drought-tolerant varieties are often higher than standard varieties; this is related to slightly improved photosynthesis efficiencies. That means they are more efficient at converting sunlight into carbohydrate in drier conditions.
Breeding maize for growth in drier conditions is not a new initiative. There are numerous existing varieties suited to drier conditions within specific regions. Many of these varieties grow over a shorter season and thus face less risk of drought. Although they do not perform as well as long-season varieties in good rainy seasons, they do significantly out-perform long-season varieties in dry seasons.
However, making these new varieties accessible to small-scale farmers presents challenges. Many of the varieties are hybrids which mean new seed must be bought by farmers every season which is an expensive exercise. On the other hand, some varieties are open-pollinated, and seed can be harvested by farmers and replanted for a limited number of seasons. The value of these new varieties also needs to be demonstrated to convince sceptical farmers of their value. These are the challenges of extension workers who, with appropriate strategies, can achieve the goal of disseminating drought-tolerant maize varieties across the spectrum of farmers.
References
Winter solstice in the southern hemisphere has just passed. The familiar Highveld rolling landscape filled with yellow hues is in sharp contrast to the lush greens of summer, indicating the poor nutrient content of the natural grasses available to animals at this time of the year. As a result, farmers in the sour veld regions face the reality... Read more
Winter solstice in the southern hemisphere has just passed. The familiar Highveld rolling landscape filled with yellow hues is in sharp contrast to the lush greens of summer, indicating the poor nutrient content of the natural grasses available to animals at this time of the year. As a result, farmers in the sour veld regions face the reality that their animal's conditions will also drop during this period. This situation, however, can be rectified by supplying the correct supplemental nutrition in the form of licks.
During the summer months in regions with summer rainfall, sour veld grasses grow abundantly, and the veld is very nutritious with animals growing well with little to no supplementation. As the season changes during the early autumn, grasses mature and sour veld grasses withdraw their nutrients from the leaves and store it in the root system for spring time when the plant is ready to grow again. The mature grass is high in fibre content while protein levels decrease. These grasses become unpalatable to animals and intake, and subsequently total energy intake, starts to decline. Where sour veld is the predominant source of energy for grazing animals, they can lose up to 20 % of their body mass during winter. Animals, especially pregnant or lactating animals therefore will need supplementation to maintain proper body conditions.
Licks provided at this stage are protein instead of energy licks because the rumen microbes have a basic requirement for nitrogen, the main component of protein. Without protein, the grazing animal will not be able to digest the grass effectively, taking longer to digest the food. Since the rumen will take longer to empty, animals compensate by lowering their intakes that in turn lead energy shortages.
Since protein is the first limiting nutrient rather than energy, protein needs to be provided in the form of a protein lick. When the microbes' needs for nitrogen is satisfied, then ingested grasses will be digested, forage intake will increase and animals will be supplied with the required energy.
Towards the end of winter however, farmers have to deal with not only low-quality grasses but an overall shortage in the available quantities of grazing grass, aggravating not only the protein issue but also the energy situation. This situation specifically has a negative impact on pregnant reproducing animals. They can be supplemented with a production lick to provide them with both the protein and the energy required during this period before the spring rains come, and grasses grow again.
For more information regarding Veld and pasture and on feeding your animals, you can log onto AgriSuite Online® where you will be able to find this information under the different animal modules.
Weather and indirectly climate affect our lives on a daily basis. While weather (Temperature, Precipitation, Humidity, Wind, and Atmospheric Pressure) refers to the daily conditions, climate refers to long term... Read more
Weather and indirectly climate affect our lives on a daily basis. While weather (Temperature, Precipitation, Humidity, Wind, and Atmospheric Pressure) refers to the daily conditions, climate refers to long term conditions. The difference between climate and weather are often described by the popular phrase, "Climate is what you expect, and weather is what you get". There is a growing recognition that climate does affect the global economic and social sectors as it directly affects insurance, health, energy and agriculture. We need appropriate climate information for planning and to make correct production and marketing decisions in terms of our agricultural activities.
Climate Data:
Two fundamental climate elements, Temperature (Min and Max) and Rainfall, are provided to the user within AgriSuite Online®. The system provides monthly total precipitation, the total early summer and late summer precipitation, the total winter precipitation, and finally the annual precipitation for the entire country. The monthly Minimum and Maximum temperature are provided together with seasonal averages and frost dates. Although various other climate factors influence agriculture, necessary decisions can be made about crop suitability and plant and harvest times based on the climate information provided.
Full lists of potential crops to produce per farm, are available as reports on the AgriSuite® system, including graphs showing the changes in precipitation and temperatures throughout the year. This information is available via the farm reports. The crop suitability information is generated by firstly determining the areas with suitable water availability (rainfall or groundwater) as well as suitable soils. First we established the areas suitable for crop production, and then we used the data to identify the climatic limits within which crop production can take place.
In most parts of the world, agriculture is solely dependent on rainfall. Droughts and floods are some of the natural disasters that can lead to crop failures, food insecurity and negative economic growth. Long-term climate records assist in the process of limiting risk when it comes to crop production.
Agricultural communities around the world continue to look for ways to cope with climate variability and still use traditional methods to predict climate behaviour.
The vulnerability of agriculture to natural climate variability and climate change can be decreased by using AgriSuite® to make more informed decisions and apply proper management practices and technologies.
Farmers are heavily dependent on climate, but they can use accurate weather and climate data to minimise the impact of hazards, either by planning to avoid the risk or by taking precautionary measures when warnings may arise.
We refer to grazing capacity as the grazable portion of a homogeneous unit of vegetation and defined as the area of land required to maintain a single animal unit without the deterioration of the vegetation or soil. To properly manage veld, one needs to balance the stocking rate... Read more
We refer to grazing capacity as the grazable portion of a homogeneous unit of vegetation and defined as the area of land required to maintain a single animal unit without the deterioration of the vegetation or soil. To properly manage veld, one needs to balance the stocking rate of various species with the grazing capacity of the veld. When discussing grazing capacity, the term "large stock unit" normally refers to an animal with a minimum mass of 450 kg, while stocking rates refer to the area of land allocated to each animal unit. Grazing capacity refers to the number of animals the vegetation can sustain under normal circumstances. Stocking rate refers to the number of animals carried on a given piece of land for a limited/unsustainable period for feeding purposes. To find the balance between true grazing capacity and stocking rates, however, is difficult to achieve since various animal species impact their environments differently.
Many factors affect the productivity of vegetation in an area. Vegetation succession, the progressive development of vegetation has an impact on the grazing capacity. Vegetation that is in a pioneer state, (Hardy species that manage to colonise previously disrupted or damaged pieces land), will be dominated by low yielding annual grasses resulting in a low grazing capacity. Vegetation in a predominantly climax state (Vegetation developed in a specific area over a length of time that reach equilibrium, adapting to the conditions present in an area), will have a higher grazing capacity. Other aspects that play an important role in vegetation productivity include the special and temporal changes in the soil and water regime, the fire regime, soil nutrients and other determinants such as altitude and slope. Intensity, frequency and seasonal grazing play a role in the long term on vegetation productivity.
A simplified grazing capacity layer is available for use on AgriSuite Online® in the Agricultural GIS section, Land-cover subsection and was developed by using a satellite-derived vegetation index. The NDVI (Normalized Difference Vegetation Index) derived product was statistically transformed using existing grazing capacity ground data. The final grazing capacity map can be used for planning purposes since it gives the user the expected grazing capacity for a specific region. It should be taken into account that the grazing capacity layer uses long-term NDVI data and that it will not be able to give information on the variability/fluctuations in grazing capacity between years. This map simply provides a guide, but the farmer will still have to adapt grazing practices according to the climatic conditions each year.
The NDVI map section was developed to provide the farmer with information about the extent of improvement or deterioration of vegetation or veld conditions. Normal NDVI conditions should always reflect the long-term grazing capacity conditions. When NDVI values increase in a region, it indicates improved grazing capacity. However, when NDVI values deteriorate, it indicates lower grazing capacity. NDVI data in the NDVI section is updated monthly to provide the user with the latest available information.
When Microsoft introduced the new user interface and user experience, Windows 8 Metro, a few years ago, most designers probably took a wide-eyed step back to review their design strategies. Well, that is what... Read more
When Microsoft introduced the new user interface and user experience, Windows 8 Metro, a few years ago, most designers probably took a wide-eyed step back to review their design strategies. Well, that is what the designers at Manstrat AIS did. The result formed the foundations of the look and feel of AgriSuite Online® as it is today.
"Content is king", ease of access, user-friendliness and scalability over different devices are just some of the keywords in the design of the user interface. The design should never overpower the content, but always empower it. We therefore used subtle but perceptible icons. While we kept colour variations to the minimum, we implemented a very easy navigational structure. The initial design process was certainly not without hiccups and it soon became a challenge to find colours that were just right over a broad spectrum of devices. We eventually solved this multi-coloured problem with a fresh green hue.
Lots of thought and effort also went into the designing of the sizes of tiles -they were measured and re-measured until we found our golden ratio. Once the base design for AgriSuite Online® was finalised, the same principles were implemented on the different modules and designing and layout came easily. Whether you are visiting the Animal Production Section, Infrastructure or Weather module, the navigation principals remain the same throughout AgriSuite Online®.
The process of designing each module starts off on the drawing board, where we tweak and stretch each element until it fits the AgriSuite Online® mould. Icons are developed for different components and finally the new layout is built using the required software and handed over to our very capable developers. In the end, 'design and layout' is just one of the many parts that make up this remarkable product.
According to the International Food Policy Research Institute, Agriculture is the primary source of livelihood for roughly 65% of Africans. This figure highlights the need for success in agriculture on the continent if economies are to grow, and South Africa is no exception... Read more
According to the International Food Policy Research Institute, Agriculture is the primary source of livelihood for roughly 65% of Africans. This figure highlights the need for success in agriculture on the continent if economies are to grow, and South Africa is no exception.
Governments, NGO's, researchers and industry players all know this and realise that agriculture can play a major role in the alleviation of poverty and the stimulation of economic growth. However, the challenge is to find a cohesive and workable plan to achieve this.
Everyone agrees on the need for easily accessible markets for smallholder farmers. Although smallholder farmers are mostly competent in animal and crop production, many do not appreciate the important role that post-production value-adding and marketing can play, and how it could reward them. This lack of knowledge and support impedes the improvement of productivity, income, food security and financial viability.
However, mere access to markets is not sufficient. Market access must include knowledge, mentoring, organisation, infrastructure, financial investment, and an understanding of marketing; that is, that the market-place is the ultimate judge. This judgement rests on the cornerstones of quality, quantity, consistency and diversity.
Farmers firstly need access to information across the agricultural spectrum, from soil preparation and crop selection to post-harvest value adding, market prices and trends. Secondly, small-scale farmers need to organise themselves into co-operational groups to ensure that they meet market demands. Thirdly there is a need for infrastructure ranging from value-adding space and equipment to proper storage facilities and transportation. There is also a need, throughout the process, for mentoring and support to ensure success. Attaining these goals will achieve collective bargaining power with both input suppliers and the market, in the form of agents, wholesalers and processors. Bulking produce will also allow farmers to reduce transport and other costs, and facilitate access to business and financial services.
Interventions by the government, organisations and ICT applications, such as AgriSuite Online®, are increasingly helping rural farmers understand how co-operation, marketing and value-adding activities open new markets to them. New markets, locally and even internationally, will mean better prices and higher profits. Profits enable reinvestment in their businesses to the extent where quantity, quality and often diversity can become a reality and ultimately improve their quality of life.
AgriSuite Online® not only provides users with the full range of production information and geo-referenced environmental information, but also information on handling, storage, and marketing of produce. The latest market prices of produce sold on the 17 Municipal Fresh Produce Markets are updated daily on AgriSuite® to keep farmers informed.
Joint efforts from all stakeholders in the industry can facilitate small-scale farmer entrance into the agriculture mainstream, which will contribute to urban development, economic prosperity, food security and political stability.
Water is a scarce resource in South Africa as approximately 66% of the country receives an average annual rainfall of less than 500mm - the minimum requirement for dry land crop production. Because of variable river flow and high evaporation, only about 62% of South Africa's average runoff... Read more
Water is a scarce resource in South Africa as approximately 66% of the country receives an average annual rainfall of less than 500mm - the minimum requirement for dry land crop production. Because of variable river flow and high evaporation, only about 62% of South Africa's average runoff can be exploited economically. Underground water resources remain an important source to utilise for various purposes.
When planning an irrigation scheme, it is vital to know what the specific crop's water requirements are, in order to ensure the availability of water. In terms of the suitability of underground water utilisation for crop production, the amount of salt present in the water is significant, as sodium compounds tend to compact the soil and destroy soil texture. Another factor to consider is that the ability of plants to withstand brackish (salty) conditions differs.
For planning and information purposes, various GIS data layers related to water are available on AgriSuite Online®. Water related information can be viewed in the Water Resources section that includes layers indicating the locations of dams and rivers, as well as the location of boreholes throughout the country. Borehole data was acquired from the Department of Water Affairs who maintain this database.
Groundwater data is available in three different layers. The Groundwater Delivery Rate data indicates the expected water availability from a particular underground water source and is useful when determining areas that will be suitable for sinking of boreholes. The delivery rates given indicate the potential for irrigation where other environmental factors for crop or vegetable production are favourable.
Groundwater Lithology data refers to the physical characteristics of rock including colour, size and sorting. This information is relevant as rocks with different lithologies have different geo-hydrological properties. The interaction between groundwater movement and geology is complex. Groundwater does not always flow downhill following topography, but often follows pressure gradients and fractures.
Groundwater Salinity is the final data layer available and refers to the concentration of dissolved inorganic salts in water that is important as high concentrations of salinity in aquifers render groundwater unfit for agricultural use.
The water and groundwater information provided on AgriSuite Online® has been simplified and generalised for fast and efficient use online and should be taken into account when using the data. It is important to remember that data provided as a source of planning and decision support can never replace fieldwork and actual physical site evaluations.
Urban agriculture includes the growing of plants (fruits, herbs, ornamentals and vegetables) and the raising of animals (cattle, goats, pigs, poultry, sheep and rabbits) within and around a city and incorporating it into the urban economic and environmental system. Urban agriculture provides fresh food for residents... Read more
Urban agriculture includes the growing of plants (fruits, herbs, ornamentals and vegetables) and the raising of animals (cattle, goats, pigs, poultry, sheep and rabbits) within and around a city and incorporating it into the urban economic and environmental system. Urban agriculture provides fresh food for residents, creates employment in the city and surrounding neighbourhoods. It furthermore re-uses urban waste (organic waste as compost), it has direct impact on urban ecology and becomes part of the urban food system.
This farming programme competes with other urban centres, such as industrial and retail areas for land use planned and governed by a city's policies. In this respect, there are health and noise restrictions in cities regarding the raising of animals. These restrictions are mainly due to the possibility of an unhygienic environment (smelly coops and fly problems), and also potential noise pollution they may create. However, there are many other types of urban farming centres in the cities, such as institutional gardens, commercial farms, community gardens and community farms that will not suffer the same restrictive measures.
Production activities take place on sites of different sizes and in various locations such as landfills, on rooftops, and on derelict residential and industrial areas. These areas of urban agriculture add value in the form of greenbelts; improve shading and the aesthetics of a city.
The overall programme integrates agricultural production, processing and marketing activities. Together with this, input and service-delivery become included in the value-chain. Urban farming involves a broad range of stakeholders, such as urban communities and neighbourhoods, city officials, project sponsors, supporting organisations and individual food growers. If managed correctly, urban agriculture can contribute to the health, social, and economic well-being of the community as well as having ecological benefits.
It has the potential of a positive impact on the city through the some of the specific benefits described below.
In many African cities, community gardens have become a significant source of fresh produce. However the shortage of resource inputs and environmental health risks remain paramount obstacles to realising the full potential of these gardens. Despite this, community gardens do increase access to food and do improve household food security, diversity of diet and contribute immensely to poverty alleviation among urban households.
NDVI images describe the vegetation activity and show the highest possible "greenness" values that were measured during a specific period. This relationship makes it possible to monitor stressed vegetation or agricultural drought conditions. Rainfall data cannot... Read more
What is an NDVI?
NDVI images describe the vegetation activity and show the highest possible "greenness" values that were measured during a specific period. This relationship makes it possible to monitor stressed vegetation or agricultural drought conditions. Rainfall data cannot show the spatial extent of drought conditions, but remote sensing data, through NDVI's can be used to map drought conditions.
NDVI in principle measures the reflectance in the RED and near-infrared (NIR) bands. Healthy vegetation has the characteristic of showing high absorption in the RED band, and higher reflectance in the NIR band. The opposite is true for stressed vegetation which will show lower absorption in the RED band and lower reflectance in the NIR band (Figure 1). This quality of vegetation is calculated and expressed in the following formula:
NDVI = (NIR-RED) ÷ (NIR+RED)
Figure 1: Illustration of NDVI
NDVI's respond in a very predictive manner to rainfall events. The resulting vegetation growth after a rainfall event can be detected between 5-10 days after a rainfall event. Drought conditions, in contrast, can only be detected after 20 days since the last rainfall event. This relationship does, however, differ according to different biomes and the availability of groundwater. The NDVI is less sensitive to high rainfall events and tends to reach a maximum value, and in instances of water stress, will show lower NDVI values.
Time series analysis further enhances the mapping of drought conditions. Images are often compared to a long-term average to show the spatial extent of drought conditions. Various statistical methods exist to calculate these kinds of maps. The Percentage of Average Seasonal Greenness (PASG) compares the accumulated greenness (NDVI) up to a specific point in the growing season to the historical average accumulated greenness.
PASG = (NDVIi) ÷ (NDVIa) x 100
where:
i = accumulated since start of season
a = long-term accumulated average
Continuous drought monitoring plays an important role in the prevention of man-made drought-related degradation. The identification and monitoring of areas affected ensures that relief can be forwarded to those who need it most. Accurate information can assist in the prediction of drought conditions and can therefore help in managing the economic risk factors.
NDVI on AgriSuite®
One of the latest additions to the Agricultural GIS section is the NDVI map section. The maps is generated on a monthly basis and provided on the system. The purpose of this map is to provide the user with information on drought conditions to assist them in the management of farming activities. Since NDVI maps are closely related to vegetation health, this can be a useful tool to manage grazing.
The role that livestock play in the agricultural sector is an important one. They are the driving force to food security and sustainable development and play a vital role in economic development. In 2013, the gross value of animal products contributed 46.6 % to the total gross value of agricultural production. In order for animal production to be successful, good nutrition and especially water is essential... Read more
The role that livestock play in the agricultural sector is an important one. They are the driving force to food security and sustainable development and play a vital role in economic development. In 2013, the gross value of animal products contributed 46.6 % to the total gross value of agricultural production. In order for animal production to be successful, good nutrition and especially water is essential. With South Africa being classified as a water scarce country, how does this limited supply impact animal performance and what can livestock owners do to protect water resources?
It is well known that food and water are essential for the survival of all animals, however, the effects of a limited feed supply is not as critical as a water shortage. Water makes up 60 % to 70 % of live weight and is an important carrier of nutrients, chemicals, hormones and metabolic wastes. It helps regulate thermal temperature and is required for the production of saliva and milk. Shortages will result in impaired growth and reproduction, and decreased overall performance.
Water is lost through milk, excreta, evaporation and respiration and is replaced each day through drinking water, feed water and metabolic water. The daily water requirement varies greatly amongst species and with age, body size and production stage within a species. In general animals consume about 3 % of live weight per day for maintenance and require more for growth, reproduction and lactation. Consumption rates are affected by environmental conditions, most specifically temperature and relative humidity levels, as well as the animals' activity levels and management factors. The water content of feeds will also have an influence on the amount of drinking water consumed.
A factor often overlooked is the quality of the water provided. Animals provided with good quality water throughout the day will consume what they need. Through experience and observation, we know that animals will not "waste" water or "luxury consume" more than what's necessary. Factors such as temperature, salinity and impurities that alter the odour and taste of water will all have an effect on the amount of water consumed. Animals deprived of water through water shortages or poor water quality often show a drastic drop in feed intake.
Livestock owners can have a strong influence on the water available to their animals. Water is often degraded and devalued by livestock production. It is up to livestock keepers to take responsibility and protect water resources. Evaporation and seepage of water from storage containers should be limited and contamination of soils, ground and surface water must be prevented as it not only affects water quality but poses health risks as well. Controlled grazing can prevent destruction of the grazing land which will help maintain ground cover and soil moisture content. Water points should be correctly positioned, and animals provided with sufficient trough space to prevent excess trampling and muddy areas developing. Log on to AgriSuite® to find out more about water sources and daily requirements for animals.
The process of growing a cropis not the only challenge that farmers face daily; they must also ensure that the crop provides aviable and sustainable living for them, and marketing of the produce is often the key to a successful business. A common method of marketing is to sell produce to a local market... Read more
The process of growing a crop is not the only challenge that farmers face daily; they must also ensure that the crop provides aviable and sustainable living for them, and marketing of the produce is often the key to a successful business. A common method of marketing is to sell produce to a local market. However,this poses its own challenges for a small scale farmer, such as transport arrangements, market costs and market needs. The question also arises: does the farmer eventually get what is really due to him? Superficial analysis would suggest there must be a better and more efficient way to get food from the farm to the table, instead of through the traditional supply chain.
The idea of a farmer selling produce does not immediately evoke a high-tech image. Despite this, the question can be asked, considering the boom in mobile technology,why not develop technology that enables farmers to sell their produce on-line directly from their mobile phones? At the same time why not enable consumers,from the comfort of their homes, to seek, buy or request fresh produce (or other products), directly from the farm?
With the trend of buying local and fresh, using technology such as this to market this kind of product,makes a lot of sense. This concept has already resulted in an upsurge of online marketsacross the spectrum of farming and agricultural communities.
AgriSuite Online® "Bids and Offers" section offers exactly this, and more, on any mobile device connected to the internet. Not only is the farmer able to "advertise" produce, but the consumer has the opportunity to request a certain product online. The "Bids and Offers" section acts as a mouthpiece for any agriculturalist with a product to sell or a need to buy. This direct online method of selling goods can be beneficial to both the farmer and the consumer as it by-passes the middleman,increasing profits to the farmer. Selling fresh produce online obviously also benefits the consumer through availabilty of cheaper, fresher produce with greater variety. Consumers buying other goods will potentially have a greater range of options and prices.
Supporting a farmer from your home-town, rather than buying imported goods, empowers local farmers and helps build local communal structures, relationships and businesses. Mobile technology (AgriSuite Online®) is an important tool used in achieving this.
The Discussion Forum on AgriSuite Online® is the direct result of the need amongst farmers and other users to have a platform where they can interact with farmers from other provinces... Read more
The Discussion Forum on AgriSuite Online® is the direct result of the need amongst farmers and other users to have a platform where they can interact with one another. The Forum affords them the opportunity to communicate "across borders" so to speak and to discuss issues of common interest, between colleagues with similar problems and situations to deal with.
One definite way in which users can assist each other and ensure that the system grows into much more of a practical tool than it would be without user contributions, is to ask questions, and reply and answer where colleagues require help. A Discussion Forum is user driven and therefore practical, and users with expert knowledge or experience have a moral duty to impart with that knowledge.
Topics for discussion are broadly divided into Animal Production, Plant Production, and General allowing users to discuss just about anything to do with their subject.
Users should remember that questions posed to Manstrat should not be posted on the Forum as the Forum solely belongs to users and the aim is for them to increase the agricultural knowledge base through their interaction. All AgriSuite Online® users are therefore urged to use the Forum to pose relevant questions, even ones that are controversial in order to stimulate and learn, for the benefit of all.
The AgriSuite Online® Classified Section was created solely for the buying and selling goods and services online, at no additional cost. As this service is available to users of the system, the feature offers a relatively safe business environment as well as the knowledge that agriculture is a mutual... Read more
The AgriSuite Online® Classified Section was created solely for the buying and selling goods and services online, at no additional cost. As this service is available to users of the system, the feature offers a relatively safe business environment as well as the knowledge that agriculture is a mutual interest factor between sellers and buyers. This knowledge will make targeting the right audience a little easier.
Placing an advert on the AgriSuite Online® Classifieds is easy, and as long as advertisers offer the right product at the right price, they have a potential market. Users should ensure that they provide clear descriptions including the description, price and contact details.
An important plus for advertisers is that they can edit their ads and change them if required, while their ad remains active. The duration of an advert is a maximum of two weeks, but a user may re-enter an advert again after the initial two-week period has expired.
The classified section of AgriSuite Online® includes a number of including Agricultural Equipment, Feed, Implements, vehicles and many more.
AgriSuite Online® users should use the opportunity, and ensure that the section grows for their own benefit.
Market information is vital to farmers and assists them in becoming competitive as it keeps them informed about market trends and marketing requirements. It also helps them with decision-making and production planning to strengthen their bargaining power. Agricultural market information in South Africa is... Read more
Market information is vital to farmers and assists them in becoming competitive as it keeps them informed about market trends and marketing requirements. It also helps them with decision-making and production planning to strengthen their bargaining power. Agricultural market information in South Africa is scattered across a wide spectrum of different sources such as commodity groups, Department of Agriculture, Banks, and other organisations. Farmers, for this reason, need to consult a myriad of sources in order to gather the required information and in the process waste time while increasing costs. AgriSuite Online®, the agricultural information system for farmers, affords them up-to-date market information through its Market Information Section.
This section contains market information on agricultural produce and other related products. The information includes market data (economic trends, analysis), agricultural statistics, trade related information, policies, and commodity group reports, legislation and other published reports covering agricultural markets in South Africa. The system provides current and historical information to allow users to make informed decisions in their respective fields. This information is collected from various sources and publications such as Department of Agriculture Forestry and Fisheries (DAFF), STATS SA, Commodity Groups, BANKS and DTI. The well-structured information is easy to understand and displayed in a user-friendly manner. Agricultural market information presented on AgriSuite Online® is not only for the benefit of farmers but also available to participants in the value chain including traders, policy makers, researchers, processors and consumers.
AgriSuite Online® successfully bridges the gap between sources of market information (government and commodity groups) and producers and plays an important role in levelling the agricultural playing field.
GIS is an acronym often used to describe Geographical Information Systems. A GIS system is a computer-based system designed to capture, store, manipulate, analyse, manage and present all types of spatial data. GIS is playing an increasingly important role in agricultural... Read more
GIS is an acronym often used to describe Geographical Information Systems. A GIS system is a computer-based system designed to capture, store, manipulate, analyse, manage and present all types of spatial data. GIS is playing an increasingly important role in agricultural production throughout the world by helping farmers increase production, reduce costs and managing their land more efficiently. Balancing inputs and outputs on a farm is fundamental to its success and profitability. The ability of GIS to analyse and visualise agricultural environments and workflows has proven to be successful to those involved within the farming industry.
Manstrat AIS houses a wide variety of GIS environmental datasets. The purpose is to provide environmental information to users for application within the agricultural sector. GIS datasets are often large and complex, and this provides a challenge in terms of its presented on an online platform. Methods need to be developed to enhance the speed in which users can access and query these datasets online. Datasets are, for this reason, simplified and stored in databases where specially developed methods guarantee the speedy extraction of information out of the database.
Storing GIS data in a database, not only enhances the speed at which it can be used and accessed, but it also provides an opportunity to combine datasets in specialised queries. Queries vary from the identification of crop production areas to the probability of pest and disease outbreaks in certain areas, at specific times of the year. The true value of these datasets only comes to the fore during the performance of specialised queries.
Current GIS data that is active on AgriSuite® include:
Farm reports can be generated by AgriSuite® to indicate all the information relevant to that specific farm. The farm report goes one step further. It shows the agricultural activities that are most likely to be successful (Crop Suitability and Grazing Capacity) in that specific area based on a combination of several of the database layers above. The closest available infrastructure is also shown together with contact details should the farmer require specific services.
The GIS data is constantly updated and maintained to make sure the most relevant and updated information is available. New data sources are also being explored to find relevant datasets that might add further value and use to the farming community. Since the data is being stored in a database, the development of enhanced products and information systems is on-going.
Gone are those days when agriculture was perceived as a dirty field, where everything was only about working in the field, under unfavorable weather conditions with spades and forks. Today things have changed; agricultural sector is like any other sector where technology is advancing every day... Read more
Gone are those days when agriculture was perceived as a dirty field, where everything was only about working in the field, under unfavorable weather conditions with spades and forks. Today things have changed; agricultural sector is like any other sector where technology is advancing every day.
With more technology involved in agriculture, youth should be inspired to participate more in the sector as it has the platform that is relevant and exciting to them. Fields of professionalism are growing in agriculture and youth can engage in the different career paths that the sector can provide. Government as a support structure is investing in youth development programs encouraging youth to take part in farming and agricultural studies as a way of overcoming unemployment and reducing poverty. It remains a fact that agriculture is the main contributor in combating food security in the country.
The Honourable Minister of Agriculture, Forestry and Fisheries, Mr.Senzeni Zokwana was quoted saying,"The government will be working to strengthen the country's agricultural training institutions over the next five years in order to attract more young South Africans into the sector". This clearly states that there is massive support from the government and its stakeholders, and with the newly advanced invented systems that make farming sustainable and easy to practise.
Helpful tools are put in place to assist anyone with interest of practicing agriculture for both business and studies. Surfing for information through thousands of books has limited people with useful information. To close the gap of knowledge deficiency, Manstrat Agricultural Intelligence Solutions (Pty) Ltd invented AgriSuite®. AgriSuite® covers a variety of agricultural information, which includes animal production. With the new information system, there is a paradigm shift as most people perceive animal production as a complex enterprise to venture in and is seen as a gender based (male dominated). The misery of surfing through books looking for better ways of starting your livestock farm is simplified and made easy to understand and implement using AgriSuite®. This tool can be used for two things, for daily farming enterprise and for study purposes.
The term drought refers to period of water scarcity and is driven in South Africa by a natural climate variability resulting in water-limiting pressures on agricultural production. Grazing capacity and crop production vary significantly from year to year mainly due to inter-seasonal climate variability... Read more
The term drought refers to period of water scarcity and is driven in South Africa by a natural climate variability resulting in water-limiting pressures on agricultural production. Grazing capacity and crop production vary significantly from year to year mainly due to inter-seasonal climate variability. Agriculturalists produce in a continuous state of uncertainty and risk, exacerbated by the unpredictability of South Africa's climate. Successful farmers are those that implement risk management, response farming technologies and water conservation practices while climate change is seen as a future threat, making the effective monitoring of drought crucial.
Drought in South Africa is driven by natural climate variability. South Africa has an average annual rainfall of 450 mm, with 65% of the country receiving less than 500 mm per annum. Years with below-normal rainfall are more common than years with above-normal rainfall. South Africa is therefore affected more by drought events than severe flooding.
Drought events put severe pressure on South Africa's already limited water resources and agricultural production. Grazing capacity and crop production vary significantly from year to year due to inter-seasonal climate variability. Although irrigation is used in many of the South African farming systems, it is affected by lowering levels of groundwater, and dams and rivers across the country, during drought events. Drought events are a limiting factor for livestock farming and game range activities throughout the country. Drought has a negative effect on overall food production and food security.
The impact of drought can be managed and reduced by appropriate policies and actions. The development of early warning systems puts emphasis on the prevention and mitigation of, as well as the adaptation to drought events.
The development of institutions, methods and capacities at government through to community level can assist in the mitigation of drought.
DROUGHT ADAPTATION and ALLEVIATION
Adaptation to drought conditions consists of initiatives and methods to reduce the vulnerability of natural and human systems against actual or predicted effects.
The safeguarding of water resources is the first step in the process of adaptation. This may include the development and use of alternative water resources, including desalinization of sea water, sinking of new boreholes, building canals to redirect water or the development of new dams. The recycling of water, rehabilitation and protection of wetlands and the prevention of water pollution is critical to the safeguarding of water resources during drought periods. In extreme drought events, water restrictions are often implemented.
Adaptation to climate changes has led to the development of new crop and seed banks, focusing on drought and heat resistant, faster growing crops. An increase in water-use efficiency and conservation agriculture helps maintain production levels within a changing climate.
MONITORING DROUGHT
Although the characteristics of drought can vary from region to region, it occurs in all climate zones throughout the world. Even though some regions are arid with low mean annual rainfall, it should always be remembered that drought refers to a state of negative deviation from the norm.
According to the World Meteorological Organization (WMO), five types of drought can be identified [1]. These include:
To effectively monitor drought, a long-term dataset is needed to monitor the balance between precipitation and evapotranspiration. Other factors to consider when monitoring drought are the start of the rainy season and the effectiveness of rain and other climate influences such as temperature, wind and humidity. The first evidence of drought is found in rainfall records while soil moisture shows the effect of low precipitation after a short period, with vegetation cover showing the effects soon after. Groundwater is lost by evaporation and through transpiration by plants - the combined process is called evapotranspiration. The effect of drought on rivers and reservoir levels is only noticed several weeks or months later.
Market access remains a big challenge for grain farmers. The high costs of production coupled with high transportation costs incurred in accessing markets for their agricultural products, reduce farmers' profit margins. Maize farmers, for example, need to buy production inputs, produce maize in order to sell in the next season... Read more
Market access remains a big challenge for grain farmers. The high costs of production coupled with high transportation costs incurred in accessing markets for their agricultural products, reduce farmers' profit margins. Maize farmers, for example, need to buy production inputs, produce maize in order to sell in the next season. With the constantly increasing prices, it is difficult for maize farmers to budget without knowledge of the selling price of maize, for planting in the next season. There are also a number of other factors that farmers have to consider before planting can commence. Amongst others, they have to take production climate, production input costs and selling price after harvesting into account. As various market forces such as supply and demand determine market prices, producers are continuously faced with high price instability that makes any planning based on potential income, extremely difficult. As such, grain farmers' have no option, but to make use of predicted market prices to plan for the selling price of their grains at the end of the production season.
The official, and most reliable tool, South African Futures Exchange (SAFEX), is used to predict grain prices. It provides information on prices obtained from the spot, and futures market of the most commonly traded grains in South Africa. SAFEX grains include soybean, sunflower, maize (white and yellow), wheat and sorghum. Although most South African grain farmers have heard of the futures market, few of them probably know how to apply this knowledge. Trading for immediate delivery by the seller in exchange for immediate payment by the buyer is typical of the spot market. The spot price is the current market price at which a commodity is bought or sold for immediate payment and delivery. On the other hand, in a futures market, there is buying and selling of specific quantities of commodities at an agreed price for delivery at a specific time in the future.
AgriSuite® mobile, links farmers to SAFEX by providing SAFEX prices to grain farmers, animal feed manufacturers, food processors and retailers, on a daily basis. AgriSuite® shows prices of the most commonly traded grains at SAFEX like yellow maize, soybeans, sunflower, wheat and white maize. To access these prices, registered users can log in to AgriSuite®, click on markets, scroll right, and click on the type of grain under SAFEX. Graphs showing spot price and closing price trends (quoted in Rands/ton) will pop up. Users have access to daily information, the previous six-day period's spot price trend, and also view the monthly closing price trend. An explanation of prices used in each graph will show when the user clicks the light bulb icon in the top right-hand corner.
The grain industry has a well-organized commodity organisation (Grain SA) as well as marketing platforms like the South African Products Derivatives (a wing of SAFEX). Due to the small scale of production and inconsistencies in the quality of their grain, smallholder grain farmers still lack access to the formal markets. AgriSuite® mobile bridges the grain information gap between the main players in the grain industry.