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The paper describes a hydrological model for agricultural water intervention in a community watershed at Kothapally in India, developed through integrated management and a consortium approach. The impacts of various soil and water management interventions in the watershed are compared to no-intervention during a 30-year simulation period by application of the calibrated and validated ARCSWAT 2005 (Version 2.1.4a) modelling tool. Kothapally receives on average 800 mm rainfall in the monsoon period. 72 per cent of total rainfall is converted as evaporation and transpiration (ET), 20 per cent stored by groundwater aquifer and eight per cent exported as outflow from the watershed boundary in current water interventions. ET, groundwater recharge and outflow under no intervention conditions are found to be 64 per cent, nine per cent and 19 per cent, respectively. Check-dams helped in storing water for groundwater recharge, which can be used for irrigation, as well minimizing soil loss. In-situ water management practices improved the infiltration capacity and water holding capacity of the soil, which resulted in increased water availability by 10-30 per cent and better crop yields compared to no intervention. Water outflows from the developed watershed were more than halved compared to no intervention, indicating potentially large negative down-stream impacts if these systems were to be implemented on a larger scale. On the other hand, in the watershed development program sediment loads to the streams were less than one tenth. It can be concluded that the hydrological impacts of large scale 2 implementation of agricultural water interventions are significant. They result in improved rain-fed agriculture and improved productivity and livelihood of farmers in upland areas while also addressing the issues of poverty, equity and gender in watersheds. There is a need for case specific studies of such hydrological impacts along with other impacts in terms of equity, gender, sustainability and development at the meso-scale.

Bundelkhand region of Central India is a hot spot of water scarcity, land degradation, poverty and poor socioeconomic status. Impacts of integrated watershed development (IWD) interventions on water balance and different ecosystem services are analyzed in one of the selected watershed of 850 ha in Bundelkhand region. Improved soil, water and crop management interventions in Garhkundar-Dabar (GKD) watershed of Bundelkhand region in India enhanced ET to 64% as compared to 58% in untreated (control) watershed receiving 815 mm annual average rainfall. Reduced storm flow (21% vs. 34%) along with increased base flow (4.5% vs. 1.2%) and groundwater recharge (11% vs. 7%) of total rainfall received were recorded in treated watershed as compared to untreated control watershed. Economic Water productivity and total income increased from 2.5 to 5.0 INR m À3 and 11,500 to 27,500 INR ha À1 yr À1 after implementing integrated watershed development interventions in GKD watershed, respectively. Moreover IWD interventions helped in reducing soil loss more than 50% compared to control watershed. The results demonstrated that integrated watershed management practices addressed issues of poverty in GKD watershed. Benefit to cost ratio of project interventions was found three and pay back period within four years suggest economic feasibility to scale-up IWD interventions in Bundelkhend region. Scaling-up of integrated watershed management in drought prone rainfed areas with enabling policy and institutional support is expected to promote equity and livelihood along with strengthening various ecosystem services, however, region-specific analysis is needed to assess trade-offs for downstream areas along with onsite impact.

Biofuel production from feedstocks grown on wastelands is considered as a means to address concerns about climate change and improve energy security while at the same time provide an additional source of income. Establishment of biomass plantations on wastelands is likely to affect local livelihoods and can affect surrounding ecosystems by influencing hydrologic flows and processes such as erosion. We present an assessment of Jatropha plantation establishment on wastelands, using the ArcSWAT modeling tool.The assessment was made for a wasteland located in the Velchal watershed, Andhra Pradesh, India, which recently was converted to a biofuel plantation with Jatropha. The previous land-use, in this case grazing, could continue in the Jatropha plantations.Several desirable effects occurred as a result of the land-use conversion: non-productive 2 soil evaporation was reduced as a larger share of the precipitation was channeled to productive plant transpiration and groundwater recharge, and at the same time a more stable (less erosive) runoff resulted in reduced soil erosion and improved downstream water conditions. A win-win situation between improved land productivity and soil carbon content was observed for the Jatropha plantations. On the other hand, the results indicate that at the sub-basin scale, reductions in runoff generation as a result of largescale conversion of wastelands to Jatropha cropping may pose problems to downstream water users and ecosystems. From a livelihoods perspective, Jatropha production was generally positive, creating a complementary source of income to the farmers, thus strengthening the resilience of the local community. In the future, the potential gain from Jatropha cropping is expected to become higher as cropping systems improve and growing biofuel markets result in better conditions for biofuel producers.

The Upper Bhima River Basin is facing both episodic and chronic water shortages due to intensive irrigation development. The main objective of this study was to characterize the hydrologic processes of the Upper Bhima River Basin and assess crop water productivity using the distributed hydrologic model, SWAT. Rainfall within the basin varies from 450 to 5000 mm in a period of 3-4 months. The basin has an average rainfall of 711 mm (32 400 Mm 3 (million cubic metres)) in a normal year, of which 12.8% (4150 Mm ) ruissellent, et le reste (63%) est prélevé pour l'évapotranspiration. La productivité de l'eau agricole dans le bassin pour la canne à sucre, le sorgho et le mil ont été estimés à 2.90, 0.51 et 0.30 kg m¯3, ce qui est significativement plus faible que le potentiel maximal habituellement rencontré dans le monde. Il y a donc des marges de progrès qu'il convient d'explorer. Différents scénarios impliquant différents itinéraires techniques ont été testés dans le but d'accroître la valeur économique de la productivité de l'eau dans le système d'irrigation d'Ujjani. L'analyse suggère que la maximisation de la superficie grâce à la fourniture d'irrigation d'appoint pour les zones pluviales, ainsi que le recours à des pratiques agricoles de gestion plus économes en eau, peuvent offrir des possibilités pour améliorer la productivité de l'eau.