Scoping of promising land management and water use practices in the dry areas of Uzbekistan

Addressing water scarcity in dryland areas requires identification of promising water-saving practices. This paper reviews the effect of land management and water use practices on Water Productivity (WP) in Uzbekistan and makes an inventory of strengths and constraints. Peer-reviewed articles were screened for various local practices including furrow, deficit and drip irrigation. The performance of practices was analysed using the WP concept, defined as ratio of crop yield per unit of water consumed (irrigation water supply and evapotranspiration). Strengths, weaknesses, opportunities and threats (SWOT) of selected practices were studied by conducting semi-structured interviews with local stakeholders in Tashkent province. This scoping process showed that overall drip irrigationhas the highest potential to improve WP in comparison with deficit and furrow irrigation, with a WP supply and WP evapotranspiration for cotton of 1.44 and 1.70 kg m(-3), respectively. An excess use of irrigation water is not necessarily leading to increased cotton yield. There is an opportunity to decrease the gap between low and high values of WP, which vary from 0.12-1.44 kg M-3 for cotton. Low water use efficiency rates of furrow irrigation are one of the key-issues to resolve for improved water management. The return on investment of drip irrigation is viable for private farms growing fruit and vegetables, which is mainly due to government support through export trade agreements and favorable policy incentives. WP values of deficit irrigation within 0-25% water stress shows that its water saving potential is high, but with certain yield reduction. The high risk of crop yield reduction is a trade-off between yield and adopting deficit irrigation. To conclude, the large gap between low and high WP values can be minimized with economically affordable technology. Beyond the technical improvements of each water-saving practice, it is also crucial to better design the system of policy incentives supporting users of the practices. Although the paper focused on Uzbekistan, the results can be beneficial to other semi-arid regions and the scoping process can be replicated elsewhere.