A Comprehensive Evaluation Of Water Use In Agricultural Production Based On The Resource-and Environment-oriented Water Footprints:A Case Study In Lake Dianchi Basin,China

Water resource has become a critical factor of economic development in a river-basin environment.From the perspective of water consumption and pollution,water footprint(WF)was provided as an indicator to assess water resource utilization related to human activities.The resource-and environment-oriented water footprints are two vital indicators for water availability assessment.The purpose of this paper is to assess and forecast the resource-and environment-oriented water footprints of crop production in Lake Dianchi Basin,China.Results indicate that:Given the water quantity and quality,virtual water(VW)conception and life cycle assessment(LCA)can be effectively used to evaluate the resource-and environment-oriented water footprints of crop production in Lake Dianchi Basin.During 2001-2012,the resource-oriented WF experienced an upward tendency,while the environment-oriented WF showed the opposite.WFg,ey was much larger than WFgreen and WFblue.Water degradation footprint(WDF)far outweighed water scarcity footprint(WSF),indicating that water pollution has placed a heavy burden on agricultural water resource in Lake Dianchi Basin.Aquatic eutrophication footprint(AEF)presented a decreasing trend,and nitrogen fertilizer had a much higher effect on aquatic eutrophication than phosphate fertilizer.According to the percentage of annual average WF of different crop production,WF of wheat ranked the first,followed by tobacco,pulse and other cereals.Vegetable and melon became the two crops with relatively lower WF.Principal component analysis(PCA)and radial basis function(RBF)neural network can be effectively adopted to predict the resource-and environment-oriented water footprints of crop production in Lake Dianchi Basin.The simulated value calculated by the defined model accorded well with the primitive data.According to the forecast results in 2015,2018 and 2020,WFblue,WFgrey,WSF and WDF showed a downward tendency.Compared with the data in 2001-2012,the total WF is relatively lower in the predicting period,indicating that the agricultural water stress and the pollution problem may be alleviated in the next few years.Nevertheless,the percentage of WFgreen and WFbiue presented a downward trend,while WFgrey showed the opposite,which constantly accounting for the majority of the total WF.In addition,the percentages of WSF and WDF were basically consistent.The results above suggest that farming structure optimization should be prioritized to mitigate water stress in Lake Dianchi Basin.The improvements in waste treatment technology and fertilizer use efficiency are also perceived to cope with water contamination and aquatic eutrophication.More comprehensive predicting models in water utilization and sustainability need to be developed during a participative decision-making process.Findings provide a better understanding of WF research on lake-basin agricultural water management,which serves as a useful reference for future studies.