How Do Droughts Affect Food Systems

The global food production depends on many driving forces and the availability of water is one. So, what are the effects of drought on crop production? What can farmers do at times of water scarcity?

1. How does drought affect agricultural production and crop yields?

It takes some 2,000 liters of water to produce 1 kg of wheat. When it comes to water withdrawal for human use, agriculture accounts for roughly 70 per cent of water abstractions worldwide. The ongoing droughts in Western Europe and in Texas will impact yield and quality of summer crops – e.g., maize , sorghum and sunflower – due to the lack of water for optimal vegetative growth, reproduction and seed development.

2. What are the effects of water scarcity on soil health and fertility?

Water scarcity means fewer leaching losses and more nutrients - especially nitrogen - remaining in the soil. Assuming heavy rainfall does not flush them out from the soil, these nutrients will be available for the following cropping season. Testing soils before the next planting season is a good practice.

3. What can farmers do to reduce – and nourish – soil during droughts?

Water helps transport nutrients to plants’ roots, and it regulates chemical and biological processes in the soils. Fertigation, the simultaneous application of water and nutrients through irrigation systems, optimizes water and nutrient use efficiency, a priority for agriculture, even more so during times of water scarcity.

4. How can farmers maintain crop productivity at times of drought and heat stress?

Climate change will increase the frequency and intensity of drought and heat stress. More resilient farming systems need to be developed. Examples include improved water conservation, no-till farming, crop and variety choices. Fertilizer best management practices can also enhance water productivity, and some nutrients such as potassium and zinc can improve tolerance to water and heat stress.