Study On Assessment Of Utility Of Agricultural Water Resources

Coexistence between water shortages and wasting and water pollution are main problems existing in water resources development and utilization in China. These problems are becoming the constraint on national sustainable development. Agriculture sector is the first place among all economic sectors on water consumption. Unfortunately, water problems are even more serious in agriculture sector, which also means that agriculture sector is the field of the most water-saving potential. Due to Versatility of agricultural water resources, the utility of agricultural water resources (UAW) are made up of not only economic benefits but also social and environmental benefits. Assessing UAW scientifically and reasonably can correctly guide the development direction of agricultural water using and promote regional sustainable development. Since, however, there is not mature theory and method on the assessment of UAW, Study on assessment of UAW has the important theoretical and practical significance.In this paper, with the guide of the theory of Sustainable Development, EESCD and Partial Equilibrium, we did study systematically on the assessment of UAW.Firstly, form human activities of water resources development and utilization, people can receive four services. Based on these basic services, this paper defined the nature of UAW and its manifestation. UAW is the comprehension of social benefits, economic benefits and environmental benefits resulted from human activities of water resources development and utilization. Based on the nature define of UAW, this paper constructed the assessment index system of UAW, proposed Theory and Methods on value estimation of UAW.Secondly, regarding nature of UAW as the core and starting point, this paper constructed assessment System of Utilization of Agricultural Water Resources (ASUAW) based on the hydrological cycle. By using the hydrological modeling for regional hydrological cycle as link, ASUAW combined the assessment of integrated utility of agricultural water with value estimation. SWAT (soil and water assessment tool) was introduced into ASUAW to be the tool of the hydrological modeling. Using SWAT, ASUAW can model evaporation process and output of crops. ASUAW was calibrated and validated with observed ET and crop yields form Daxing irrigation area. The simulated processes coincide with the observed processes, which mean ASUAW can use the hydrological modeling result of SWAT to assess UAW.Thirdly, this paper tried to discuss scale effect of UAW and their conversion relation among different scales. Based on irrigation water cycle, WUE was emphatically discussed.In this paper, we try to do some innovation as fellow:First, starting from service functions of agricultural water resources, the nature of UAW and its manifestation were defined. Based on this, theory and methods of assessment of UAW are proposed.Second, According to the economics perspective, this paper tried to explain the source and nature of utility value of agricultural water resource. By using of idea of opportunity cost, the method on value estimation of agricultural water resources were proposed. ?Third, based on the hydrological cycle, ASUAW are constructed, which has two main jobs: assessing the integrated utility of agricultural water, estimating utility value of agricultural water.