Eroding food security - Cropland soil loss in the Rwenzori mountains of Uganda [Solozori]

• Applicants: Professor Dr. Peter Fiener; Dr. Florian Wilken
• Subject Area: Soil Sciences
• Term: since 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 549583590

A critical hotspot for rising food demands fused to massive soil degradation is Africas Albertine Rift due to steep terrain, heavy erosive rainfall and low soil cover conditions throughout the cultivation period. The pressure on land resources leads to various problems that will have a tense ecological and social impact (food insecurity, political unrest, migration). As soil loss under arable use tremendously exceeds soil formation at sloped fields, agricultural use is limited to a certain period of time. After the fertile soil mantle is removed (bedrock is exposed to the surface), these areas lose their ability to host any kind of healthy biotic community quasi-permanently (millennial-scale). The time it takes to remove the soil mantle is heterogenous and controlled by the local soil loss rate and soil depth to bedrock. The main objective of Solozori is to understand and quantify the ongoing soil degradation dynamics and its effects upon cropland productivity, soil health and finally ecosystem service collapse. The study is planned in the Rwenzori mountains in Uganda, where land use pressure leads to deforestation of steep slopes that rapidly degrade (within decades) and soil productivity collapses due to shallow soils. Due to these shallow soils, the region is a perfect showcase to study processes associated with soil resources limitations that will in the longer run accelerate food insecurity impacting vulnerable subsistence farmers and partially impedes the chance for successful reforestation in the entire Albertine Rift region. Solozori utilises remote sensing to understand land use history and patterns of vegetation dynamics, while proximal sensing topographic landscape features and fallout radionuclides shed light on long-term soil redistribution rates. Soil redistribution rates will be reflected against soil resources (soil depth to bedrock) to get a grip on the spatial extent and remaining time until cropland loss in the Rwenzori mountains. Thereby, Solozori provides a showcase on yield effects caused by soil resources scarcities and serves the vital need to understand long-term soil degradation dynamics to find sustainable solutions that reduce land use pressure on forest resources and mitigate the dramatic loss of forest resources and corresponding ecosystem services. Solozori puts soil system collapse into a temporal perspective and is a first stepping stone to predict soil ecosystem services loss in the African tropics.

• DFG Programme: Research Grants
• Co-Investigators: Professor Dr. Karl Auerswald; Dr. Paul Wagner