Application Of Improved Catastrophe Evaluation Method In Agricultural Drought In Henan Province

With the obviously change of global climate and the gradually increase of water resources demands.The drought risk of agricultural system in our country is also increasing.Therefore,it is necessary to strengthen the risk research and providing theory foundation for science management of agriculture disaster risk in China and the making strategy of preventing disasters and reducing damages.This paper takes Henan Province as the research object.It is based on the comprehensive analysis of agricultural drought risk and natural disasters risk and proposed an analyzed method of agricultural drought disaster risk based on catastrophe theory.It used this method to analyzed and evaluate the Henan Province agriculture drought risk.It achieves the results and conclusions as following:(1)This paper analyzes and research the characteristics of agricultural drought in Henan Province.It analyzed the causes of the drought from the risk factors,the vulnerability of the carrier,the exposure and the ability of drought resistance.Combing and analyzing the basic concepts of drought,drought disaster and agricultural drought risk,etc.In addition to the traditional drought risk analysis method,It also can make the agricultural drought disaster reduce to the natural disaster category and research it using the related concepts of disaster system.(2)Forming natural disaster risk can divided into four aspects of the formation of agricultural drought risk,dangerous,vulnerability,exposure and drought resistance according to natural disaster risk theory.On this basis,it build evaluation index system of agricultural drought in Henan Province,according to the selecting principles of evaluation indexes and combining actual situation in Henan Province and to determine the weight of each evaluation index,and build assessment model of the agricultural drought risk of Henan Province.(3)We established a comprehensive evaluation model according to catastrophe theory,and improve catastrophe assessment method through adjusting initial comprehensive value and the method of constructing the fitting function,so as to improve the level of resolution ratio of comprehensive assessment value and it can be more intuitive to difference grade and size evaluation value.(4)Using the catastrophe evaluation model to assess and analysis the risk of agricultural drought in Henan Province,on the one hand,assess and analyze from the hazard risk,vulnerability of carrier,exposure and drought resistance,etc.;on the other hand,evaluate crops production from the climate factors,agricultural materials,production conditions and water conservancy and other aspects.Having further rank classification of agriculture drought risk in Henan province through the analysis of grain production in each cities.Finally,having corncultivation in Henan Province as the research object.Making corn growth cycle divided into the following four stages according to areas corn growth cycle.The first stage,from sowing to seedling(June);The second stage,from jointing to heading(6-7 months);The third stage,from heading to ripeness(7-8 months);The fourth stage,from ripeness to harvest(8-9months),at each stage to calculate the from air pressure,temperature,humidity and precipitation based on category method.To analyze agriculture drought disaster in Henan Province based on the calculation result.