Modeling Impacts Of Climate Change On Water Resources And The Yields Of Winter Wheat In The Haihe River Basin

Haihe river basin is located in North China with high population density and rapid economic development, which occupies an important position in china’s politics and economy. However, extremely scarce water resource in the area has become an important limiting factor of the development of agriculture. Under the influence of global climate change, the average temperature in Haihe River basin is undergoing a significant upward trend while precipitation is gradually declining. It is significant and urgent to scientifically assess the impact of climate change on water resources and food production, which may be helpful to water resources management and agricultural management.Based on the studies of the characteristics of the climate change, water resources, agricultural productivity in this basin, a distributed hydrological model-SWAT model was used to establish the hydrological cycle and the winter wheat crop management processes, and model parameters were calibrated and validated. Then nine different climate change scenarios including irrigation were projected to analyze the average changes in water resources and food production. Finally the adaptation measures responding to climate change were proposed for water management and agriculture management. The results revealed that:1) The average precipitation has a decreasing trend for many years, with an average reduction rate of20.7mm/10a, the average temperature has fluctuated upward trend, warming with the rate of0.32℃/10a; total water resources shows a downward trend and interannual variability significantly while the amount of surface water resources is reducing with the rate of3.23billion m3/10a; per capita food production is relatively lower.2) When precipitation decreasing by10%, temperature rising1℃and the combination of the two factors, the Blue water resources will reduce by19%,3%and29%, while the ratio of green water to blue water, respectively increases to4.6,4.9and5.8.3) under different climate change scenarios as well as irrigation scenarios, watershed average changes of winter wheat, water consumption, irrigation, crop water productivity and the irrigation productivity are in range of-13.38%-+2.03%,-2.81%-+6.19%,-4.43%-+10.35%and-2.58%-12.71%, respectively.4) In order to cope with the impact of climate change on water resources, food production and crop water productivity, some adaptation strategies are proposed including:improving water use efficiency, increasing water conservancy constructions, strengthening coping strategies and optimizing the allocation of water resources management, unifying management of water resources for water resources management responded measures, and improving irrigation facilities and warning and mitigation capabilities and transformation of government functions for crop management responded measures.At the end of the paper, the limitations and prospects for future courses of the study are discussed, and I expect that a more comprehensive of the current and further research will really apply practical use to the management and decision-making.