Water scarcity is already widespread and remains on the rise: it is found in nearly every region in the world. Around 36% of the world’s population is currently living in water-scarce regions. This publication shows that avoiding, reducing and reversing land degradation have positive long-term gains in water security. As land degradation and water scarcity are closely linked, and water is the most disruptive element in the on-going climate change crisis, how land is managed plays a major role in taming this disruption.
LDN and water
Water scarcity is already widespread and remains on the rise in nearly every region in the world. Around 36 per cent of the world’s population is currently living in water-scarce regions. Avoiding, reducing and reversing land degradation lead to positive long-term gains in water security. As land degradation and water scarcity are closely linked, and water remains the most disruptive element in the ongoing climate crisis, how land is managed plays a major role in taming this disruption.
The current decrease in water quality and availability due to more prolonged and intense droughts will continue if land degradation and climate change trends stay in place. Integrated land and water management provides a cost-effective, long-term solution to water scarcity, drought and air pollution. Sustainable farming practices help increase organic matter in the soil, which leads to improved water-retaining capacity and water use efficiency. Mulching with crop residues, introducing legumes as cover crops and inter-cropping with trees are all efficient ways to build soil organic matter, helping reduce water runoff and improve soil fertility.
A study of 40 sustainable land and water management technologies documented by the World Overview of Conservation Approaches and Technologies (WOCAT) found that nearly 88 per cent of assessed technologies led to an increase in soil moisture. Reduced runoff and increased water infiltration and storage in the soil also led to greater water availability. Additionally, sustainable land and water management technologies led to reduced evaporation in drier environments. Better land management practices make an important contribution to reducing competition for water resources. Water pollution caused by land degradation and unsustainable practices also affects water quality. Conventional water treatment removes unwanted contaminants such as pesticides and nutrients, but at significant energy and financial costs. Implementing SLM measures and reducing land degradation in drinking water catchments can prevent the pollutants from entering water supply, reducing the cost of water treatment. Promoting LDN in headwater catchment areas also helps minimize soil erosion, which in turn reduces siltation in water dams, bringing down maintenance costs and increasing the lifespan of water reservoirs and hydroelectric infrastructure. Planning and implementing LDN at the watershed level can revolutionize integrated natural resource management and help build resilience against drought and other climate change impacts.