AGRICULTURAL
Resilience in agriculture and water sustainability :
Towards 2025
Agriculture has managed to reshape our natural world more than anything else . To produce our food , an enormous amount of water is required . If the current trends in water consumption required for food production continue , we face a looming crisis . It is closer than we think .
� By Yolandi Schoeman Ecological Engineering Institute of Africa
Southern Africa is the second region in the world to be confronted by a debilitating water deficit . In addition , South Africa is classified as a semi-arid country . Future forecasts predict more erratic weather patterns for South Africa , where rainfall will become more infrequent and intense .
It is predicted that by 2025 South Africa will experience physical water scarcity and even a possible depletion , placing significant pressure on agriculture to become more efficient .
Only 12 % of South Africa is suitable for the production of rain-fed crops , with productivity tracking rainfall . Further , irrigation also accounts for approximately 63 % of the total water usage in South Africa that consequently takes place on approximately 1,1 % of South Africa ’ s total land surface area .
Agri-business remains a challenging business and is mostly regarded as being unsustainable towards conserving natural resources . More water-smart innovative thinking is required in agriculture to ma nage and utilise water more efficiently to promote sustainability and to ensure that agriculture survives and flourishes in the 21st century . With the application of water conservation and demand management principles , in both irrigation and rainfed crop production , the agricultural sector will have a significant positive effect on the availability of water to other sectors .
There are several efficiencies that can be implemented in the agricultural sector that include an increase in supply and reducing demand .
To increase water supply , the following can be applied in agricultural practices :
� Remove alien invasive plants and replace with indigenous water-smart vegetation , especially in wetland areas ;
� Conserve wetlands by removing alien invasive plants , coupled with controlled burning and grazing .
� Build constructed wetlands to treat agricultural wastewater that will increase water availability for both crops and livestock and that can mitigate fresh water salinity and nutrient enrichment resulting from agricultural practices .
� Leave at least a 30-40 m natural vegetation buffer between cultivated lands and a river , and a 25-70 m buffer around a wetland .
The following are also good practices that can be implemented to reduce demand :
� Build up soil organic matter to reduce evaporative water loss and to maximise the water holding capacity .
� Use more efficient and smarter irrigation systems , such as drip irrigation , that can save up to 80 % of water consumption and ensure regular maintenance takes place . Also consider crop type , soil water status , soil type and weather conditions with irrigation design .
� Register water usage with the Department of Water Affairs , where necessary .
� Know your water footprint and water balances by measuring water consumption and recording actual water usage .
� Implement water-recycling techniques and water harvesting where possible .
� Consider using drought resistant plant and animal species .
Virtual water and the exporting of water is also an upcoming innovative water management strategy that will become more important in South Africa in the near future . Eco-agriculture or nature farming is an emerging ecological engineering field that has already been successfully implemented in parts of South Africa ( for example the success story of ZZ2 ) and that is exponentially growing in implementation .
It is inevitable that we need to implement more proactive water conservation practices more aggressively towards 2025 and beyond , and ensure our agricultural practices become resilient . For , resilience is key to the survival of the agricultural sector . It just makes business sense .
For more information contact Yolandi Schoeman at schoeman . yolandy @ gmail . com .
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SENWES SCENARIO | SPRING 2018