African rainforest moisture contribution to continental agricultural water consumption

Abstract

Precipitation is essential for food production in Sub-Saharan Africa, where more than 80 % of agriculture is rainfed. Although ∼40 % of precipitation in certain regions is recycled moisture from Africa's tropical rainforest, there needs to be more knowledge about how this moisture supports the continent's agriculture. In this study, we quantify all moisture sources for agrarian precipitation (African agricultural precipitationshed), the estimates of African rainforest's moisture contribution to agricultural precipitation, and the evaporation from agricultural land across the continent. Applying a moisture tracking model (UTRACK) and a dynamic global vegetation model (LPJmL), we find that the Congo rainforest (>60 % tree cover) is a crucial moisture source for many agricultural regions. Although most of the rainforest acreage is in the DRC, many neighboring nations rely significantly on rainforest moisture for their rainfed agriculture, and even in remote places, rainforest moisture accounts for ∼10–20 % of agricultural water use. Given continuous deforestation and climate change, which impact rainforest areas and resilience, more robust governance for conserving the Congo rainforest is necessary to ensure future food production across multiple Sub-Saharan African countries.