Socio-ecological resilience to soil erosion driven by extreme climatic events: past, present and future challenges in East Africa.

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With growing land-use pressures and consequent severe soil erosion, many East African socio-ecological systems are at a tipping point. Continued and accelerating soil erosion presents a credible threat to community and ecological resilience to future climate change shocks.Soil erosion and downstream siltation problems challenge water, food and energy security, with growing threat from climate change. Even under 'normal' climatic conditions, soil erosion reduces water and nutrient retention, biodiversity and plant primary productivity on agricultural land putting stress on food production, notwithstanding ecosystem and water resource/power generation impacts downstream. This undermines the resilience of communities that depend on soil and water resources, and shocks are often amplified by physical and socio-cultural positive feedback mechanisms. Shocks can, however, lead to a learning experience that propels a system to a qualitatively different pathway. This can support greater-than-previous levels of resilience (sometimes termed 'bounce back'). Co-production of sustainable land management practises will help enable agrarian and pastoral communities to (1) withstand shock of future extreme hydro-climatic events and (2) recover from prior environmental impacts to a resilience level beyond the prior state through restoration/enhancement of degraded landscapes.Facilitating a step change in land management practice to reduce complex soil erosion impacts is a fundamental target within the UN Sustainable Development Goals, a challenge that requires an interdisciplinary approach. To bring about urgently needed change in land management practice behaviour, evidence is required to demonstrate how social resilience is intrinsically linked to landscape/ecological resilience through the coupled co-evolution of natural resource systems and dependent rural communities.The East African Rift System (EARS) region has the highest catchment sediment yields of sub-Saharan Africa linked in part to topography and rainfall but also to recent and historic land conversion to agriculture and, in particular, increasing livestock numbers on grasslands. Extreme drought and rainfall events, which are already a characteristic feature of tropical climatology (e.g., linked to ENSO), are widely accepted to increase in magnitude and/or frequency with global climate change. There is a real risk that, in the absence of community-owned soil management programmes, recent land use change will amplify hydro-climatic and consequent societal impacts. This is exacerbated by socio-cultural lock-ins such as power and esteem gained by owning livestock, putting pressure on fragile ecosystems and ecosystem services, with repercussions for economic and human health.Experts in soil erosion and land degradation problem identification are not necessarily experts in socio-economic and socio-cultural solutions. To tackle this challenge, we propose an interdisciplinary approach to designing sustainable land management practices that would enable rural communities affected by soil erosion to overcome post-erosion shocks and achieve a higher level of resilience than previously. Through novel integration of environmental science, arts and humanities and social science evidence, this project will map out potential behavioural changes and how these can be embedded in the design and implementation of soil conservation and restoration strategies. The interdisciplinary approach in this foundation-building programme will develop knowledge of complex interlinkages between soil degradation, climate change, and community resilience in the EARS region, as well as to explore pathways to possible solutions. Interdisciplinary evidence of the problem will be explored against complex socio-cultural community concerns and needs, and potential solutions will be considered with stakeholder groups to identify and underpin future behavioural change in land management.