Assessment Of Drought For Agricultural Impact And Crop Pattern Adjustment Countermeasures Of Drought

First we revise The Palmer Drought Severity Model , then we make a dry-wet regionalization of the study area . And make a analyze about the influence of dry-wet condition on crops production potential . At last , We use virtual water strategy and crop arrangement to deal with drought.The Palmer Drought Severity Model is an important model to estimate the severity of drought. After being introduced into China in the 20th century. A series of corrections have been made by An Shunqing etc, most of them did the operations with the data from single sites, but these are not appropriate for researches over a large scale. We averaged the single data and then do a intergration for each area. We construct the model with seven typical sites of Liaohe basin in Liaoning. And we used as basic data and relevant data gained at other 23 stations from the Haihe-Luanhe River basin,the Huai River basin,the Yellow River basin and the Changjiang River basin to obtain the weighting coefficient, and we use the Synthetical Water Equilibrium Model replace the former one. After the corroboration, it shows that the result accords with the fact, and be meaningful to the research of regional drought.When make the regionalization , we also link dry-wet to crop production potential , analyse the influence on crop production potential .We use virtual water strategy and crop arrangement to deal with drought . Virtual water is a new conception of the realm of Water resources , which was bring forward by some foreign scholar in the 90's past century , It reflects the requirement of water resources about the goods and services which produced by products .this text aim at the grain crops in different regions of Liaoning Province , analysis and deal with the interrelated data , thereby to reach the research purpose of the Virtual water of different regions' grain crops in Liaoning Province . Crop pattern means the Regional distribution of crops , A reasonable crop pattern can give full play to natural resources and economic condition . Increase output and quality of crops , and make a good benefit of economic, ecological and social . Reduce the unnecessary water resources waste . Achieve the purpose of abate drought influence .