Paper for presentation at the 27th SSEA/6th ASSS Conference held on October 20-25, 2013 in Nakuru, Kenya | To evaluate the performance of drought tolerant maize varieties under different water harvesting technologies (zai pits, tied ridges and conventional), the treatments were laid out in a split plot design with water harvesting methods as the main plots, and maize varieties as the sub-plots. Four maize varieties were evaluated under the three water harvesting technologies. Maize yields in zai pits and tied ridges treatments were significantly higher than for conventional treatment. Maize constitutes a major component of the diet in the region, with more than 70% of maize cultivated by farmers in small holder units of less than 20 hectares of land.

As befits a CGIAR Challenge Program , the CPWF has welcomed a wide range of stake holders and partners in accord with their ability to achieve program goals. Decision on research investments (project selection) have been based on a competitive grants in which proposal quality was evaluated by an interdependent external panel. The usual weakness of a competitive grants approach - lack of coherence in research agenda has been address by Basin Focal Projects and synthesis research.

There are many options for enhancing food production from fish in managed aquatic systems.The most appropriate technology, however, will vary from place to place, and the conditions under which one technology is prefered over another are still not well defined.

Summary of ongoing PhD research presented as a poster at the University of Edinburgh Royal (Dick) School of Veterinary Studies Annual PGR Conference, 23 April 2024

This reports summarizes and synthesizes activities and achievements of the CGIAR Challenge Program on Water and Food (CPWF) through the end of 2007. The CPWF is an intiative of the CGIAR designed to take on the global challenge of water scarcity and food security. It is an international, multi-institutional researchfor- development initiative that brings together scientists, development specialists and river basin communities, and seeks to create and disseminate international public goods (IPGs) helpful in achieving food security, reducing poverty, improving livelihoods, reducing agriculture–related pollution, and enhancing environmental security. The CPWF conducts its research on water and food in nine ‘benchmark’ river basins, organized around five different themes. This work is being implemented through competitive-call projects, Basin Focal Projects (BFPs), small grant projects and synthesis research. This report is one example of the latter. Projects and outputs Part of the CPWF’s work has focused on increasing water productivity in rainfed environments. Achievements include the further development of conservation agriculture for no-till sowing into crop residues; “slash and mulch” to replace “slash and burn” practices in hillside agriculture; water harvesting systems for dryland locations; understanding livelihood vulnerability and farmers’ coping strategies; and developing and encouraging the distribution—through community ‘participatory’ varietal selection and seed schemes—of drought-tolerant sorghum, wheat, and other crops. Progress has also been made in increasing water productivity in irrigated and salt-affected environments, especially where water is scarce and there are opportunities to increase its productivity. Examples include the development and testing of salt-tolerant germplasm for rice and other crops to make more effective use of salt-affected areas; understanding how to use wastewater in irrigated peri-urban agriculture to produce safe and nutritious vegetables; and developing aerobic rice germplasm and management practices to produce more rice with less water.

The paper proposes a probabilistic approach to the assessment of the impacts of multipurpose dams. It is framed around the notion of Nature’s Contributions to People (NCP) in the setting of the Water-Energy-Food nexus. The socio-ecological context of the Tana River Basin in Kenya and the construction of two multipurpose dams are used to highlight co-produced positive and negative NCP under alternative river regimes. These regimes produce both damaging floods that ought to be controlled and beneficial floods that ought to be allowed. But the river regime that results from hydropower generation and flood risk reduction may not be the one that is most conducive to food and feed-based NCP. The approach relates the economic value of river-based NCP coproduction to the probability of flooding to derive the expected annual value of NCP and a NCP value-probability curve. The relation between NCP flows and flood characteristics is tested and estimated based on regression analyses with historical data. Results indicate that the net economic value of key NCP associated with multipurpose dams for local people and associated social equity effects largely depend on the frequency of flood events and on the way impacts are distributed across communities, economic sectors and time.