Study On Agricultural Cropping Systems Adjustment And Benefit Evaluation Of South-to-North Water Transfer East Route In Jiangsu

Water is the lifeline of agricultural production, The shortage number and uneven distribution of space is the main constraint factor in Chinese agriculture. South-to-North Water Transfer is an effective measure to solve the uneven distribution of water resources and the contradiction between supply and demand. It affect regional agricultural cropping systems and the sustainable development of regional agriculture.Jiangsu Province not only is the water source place of South-to-North Water Transfer East Route (SNWTER) , but also is the important reception basin. In order to play a more efficient function and efficiency of water diversion project, the paper recalled the research of relevant domestic and international water resources used effectively in the cropping systems, and analyzed systematically the influence of the water resources along SNWTER in Jiangsu on agricultural multiple index, distribution and plant efficiency.Among the main contents include the following:(1) On the basis of Cobb-Douglas production function, by using agricultural irrigation water per hectare, the total power of agricultural machinery per hectare, fertilizer use per hectare as a factor, the paper established multiple cropping index of the input-output production function, analyzed the influence of the SNWTER on multiple cropping index. 1996 as datum year and 2009 as planning years, this paper analyzed the water resources along SNWTER in Jiangsu contribution degree to the multiple cropping index. The results showed that the contribution of water resources to multiple cropping index in the 1997-2002 is gradually increasing , the average growth over 10%. Contribution to the rapid increase is Pizhou and Peixian, with an average increase of 26%, 28%. With the water-saving irrigation technologies and construction of water conservancy projects improved step-by-step, the contribution degree of water resources on multiple cropping index will gradually reduce and eventually tend to be balance after 2009.(2) The paper analyzed the changed direction of cropping structure and cropping efficiency after running water transfer project based on the mathematical model of linear programming in conditions of water resources, the greatest economic efficiency as the main target. The results showed that compared to 2005, the sown area of rice, vegetables and other crops along the Jiangsu section will increase in 2009, the average growth is 6 percent or more. Wheat, soybean, corn and other crops sown area reduced by an average of 8%. But cotton, potato and other crops that had unobvious regional advantage remained unchanged. With the operation of the water transfer project, agricultural output value of cities is expected that increased by 10% in 2009 than in 2005.(3) In accordance with comprehensive, scientific and operational principles etc., the paper established a multi-level cropping systems benifit assessment index system by comprehensive use of the Delphi method, expert evaluation and AHP. Based on the Analytic hierarchy -grey correlation complex model, the paper analyzed and evaluated the eco-efficiency, economic benifits, social benifits and comprehensive benefits about the agricultural cropping system of eight counties ( cities) in the study area. The results show that the social efficiency of cropping systems were stably developing in the cities; Compared to 1996, all regional economic benefits emerge upward trend and increase more than 100% in 2009, the growth rate of economic benefits is highest of Pizhou and Peixian, reaching nearly 150%; The ecological benefits of the study area increases about 20%; Study of comprehensive benifit of cropping systems shows a steady trend and increase by 50% in 2009.