Water scarcity is considered to be one of the largest threats for many parts of Africa. Under water scarce conditions reducing the consumption of water and preventing pollution of accessible water resources is essential. Combating water scarcity in both dimensions of quality and quantity is of special relevance for the LNV priority regions (including those in Water Mondiaal). Future LNV policies to address food security in Africa will affect the use, spread and fate of agrochemicals as well. Very little information is available on how this might effect the ecosystem approach (including biodiversity, increased resilience, and multiple-use potential) in land use planning

In this knowledge compendium a series of contributions illustrates how Wageningen UR cooperates with African organizations in finding innovations to combat water scarcity and to deliver the scientific knowledge necessary for future actions. In most of these activities, the integration of the formal knowledge of WUR with the tacit knowledge of the local stakeholders plays an important role. The Dutch Ministery of Economic Affairs, Agriculture and Innovation (EL&I) has stimulated the preparation of this compendium to disseminate the knowledge on these innovations among stakeholders throughout the African continent. This knowledge compendium presents a selection of recently finished research projects or on-going projects on water challenges in African food security. They are clustered under four themes: (1) challenges; (2) advances in research; (3) adaptation and implementation; (4) knowledge transfer. The contributions aim to stimulate further research and cooperation as a basis for the development of further management measures.

In this knowledge compendium a series of contributions illustrates how Wageningen UR cooperates with African organizations in finding innovations to combat water scarcity and to deliver the scientific knowledge necessary for future actions. In most of these activities, the integration of the formal knowledge of WUR with the tacit knowledge of the local stakeholders plays an important role. The Dutch Ministery of Economic Affairs, Agriculture and Innovation (EL&I) has stimulated the preparation of this compendium to disseminate the knowledge on these innovations among stakeholders throughout the African continent. This knowledge compendium presents a selection of recently finished research projects or on-going projects on water challenges in African food security. They are clustered under four themes: (1) challenges; (2) advances in research; (3) adaptation and implementation; (4) knowledge transfer. The contributions aim to stimulate further research and cooperation as a basis for the development of further management measures.

In a context of future population increase and intensification of water cycle by climate change, water demand for irrigation is projected to double. However, freshwater resources have been degraded the last decades especially in rivers via fragmentation, dam contraction and pollution. Flow alteration and degradation lead to 80% of freshwater ecosystem species loss. In this thesis, a robust and reliable Environmental Flow (EF) method was developed for global scale: the Variable Monthly Flow (VMF) method. This method allowed estimating EF deficit at global scale including its origin, timing, frequency and magnitude. By setting EFRs as priority user in a global vegetation and hydrological model (LPJmL), irrigation loss due to EFRs implementation were assessed at 30% leading to 5% global calorie loss. To maintain water allocation to humans and ecosystems under global change, food imports would require to increase by 15% especially from Latin America to South of Asia.

In a context of future population increase and intensification of water cycle by climate change, water demand for irrigation is projected to double. However, freshwater resources have been degraded the last decades especially in rivers via fragmentation, dam contraction and pollution. Flow alteration and degradation lead to 80% of freshwater ecosystem species loss. In this thesis, a robust and reliable Environmental Flow (EF) method was developed for global scale: the Variable Monthly Flow (VMF) method. This method allowed estimating EF deficit at global scale including its origin, timing, frequency and magnitude. By setting EFRs as priority user in a global vegetation and hydrological model (LPJmL), irrigation loss due to EFRs implementation were assessed at 30% leading to 5% global calorie loss. To maintain water allocation to humans and ecosystems under global change, food imports would require to increase by 15% especially from Latin America to South of Asia.