Study On Evaluation And Optimal Allocation Of Agricultural Water Resources In Liaoning Province

Liaoning Province is one of the provinces with the most severe water resource deficiency.The water quantity per capita and per unit area of cultivated lands are both one third of the country's average indices respectively,ranking the third last in the country. Agriculture,as the main water consumer,consumes approximately 68 per cent of the total water supply.With the increase of population and the acceleration of industrialization and urbanization,but with little potential for increase of total water supply,the weight of agricultural water consumption in the total social water consumption will definitely decrease gradually.The lack of agricultural water resources has become an important factor which hampers the development of agriculture as well as social economy of Liaoning.This paper studies on the situation of agricultural water resources targeting Liaoning Province which is divided according to administrative districts.The main research subjects and conclusion are as follows:(1)Calculating the quantity of agricultural water resource of Liaoning taking Year 2005 as the current year.The quantity of the Liaoning agricultural water resource in total is 79.777 billion m~3,or 74 per cent of the precipitation of that year.Among which,,soil water resources is 41.763 billion m~3,making up 52 per cent of the agricultural water resources. Therefore,soil water is an important agricultural water resource although it is not a gravitational water.(2)According to the amount of water resources of Liaoning from 1991-2000 and the statistical data of the area of cultivated lands in 2000,establishing a matching analysis model of agricultural land and water resources.Simulated analyses indicate that matching coefficient of water and land of Liaoning is low,with unbalanced temporal and spatial distribution is not balanced.The matching coefficient is 0.55,below the country's average. The distribution in each administrative district in Liaoning is unbalanced.The best one is Dandong whose matching coefficient is 3.16,and the worst one is Fuxin whose matching coefficient is 0.12,about 26 times.(3)In order to better achieve the assessment of sustainable utilization of agricultural water resources in Liaoning Province,this paper establishes an assessment index system for sustainable utilization of agricultural water resources in Liaoning and confirms the weight of each index,by a combination of Delphi and AHP(analytic hierarchy process) methods,applying the theory of agricultural water resources system.The index system consists of three layers including eighteen indices,then evaluates the present situation of the sustainable utilization of agricultural water resources in Liaoning based on fuzzy comprehensive evaluation method.The results show that the membership of sustainable utilization of agricultural resources is 0.4576,with the best city,Shenyang.The assessment index system is able to reflect the authentic condition of the sustainability of the agricultural water resources in Liaoning.(4)According to the relative information from 1996-2005,establishing a forecasting model applying the theory of grey system and the combination of the grey system and the logistic equation respectively.This paper forecasts the effective irrigation areas in Liaoning from 2006-2010 and the agricultural water consumption in Liaoning Province and each administrative district.The results show that the effective irrigation area will reach 1.534 million hm~2 by 2010,and the agricultural water consumption will be 10.575 billion m~3.(5)According to the principle of macro-system decomposition coordination and solving the dynamic programming model,conducting an optimizing allocation to the limited agricultural water resources in Liaoning.This paper mainly optimizes the agricultural irrigation water of the food crops.According to the planting and irrigating situation of the cereal crops in Liaoning,choosing 3 typical cereal crops:paddy rice,corns and wheats.The optimizing results show that the planting areas of the paddy rice,corn and wheat are 806.4 thousand hm~2,1.6374 million hm~2,50.2 thousand hm~2;the yeilds have reached 8.879 billion kg,13.584 billion kg and 0.173 billion kg respectively;the total profit has reached 42.447 billion yuan.Finally,it concludes the research results and points out the existing problems of the management and utilization of the agricultural water resources in Liaoning,and has a prospect of further research in this area.