Flood Risk Assessment Of Agriculture Based On GIS

The floods are the most serious natural disasters in the world, whose characters are broadinfluence, suddenly happening and high frequency. And it has posed a huge threat to people’sproduction and life. Due to the influence of climate and geographical conditions in China,large area is affected by the floods every year. According to statistics, about27.5%ofeconomic and food losses are caused by floods. In some individual serious rain waterloggingyears, loss is more serious. For example, flooding of Jianghuai areas in1991, only Anhui andJiangsu Provinces the Grain output reached12billion kilogram. In order to provide basis formanagement to make decision, disaster risk assessment research seems very important.The flood is the most serious disasters in Jianghuai areas. So in this research, taking Guzhenarea of Anhui Province as an example, analyzed the reasons of the disaster from three aspectsbased on the theory of regional disaster. Taking physical geography and natural disaster riskscience theories as basis, agriculture as the research object, using hydrologic-hydrodynamicmodel combine with high accuracy DEM data of the study area, using the ArcGISenvironment Python language to simulate possible inundation area and submerged depth by aheavy rain. Established exposure assessment model according to the concept of agriculturalflood disaster exposure framework. Using remote sensing processing technology combinedwith field investigations to extract Guzhen County crop farmland area, gridding the GuzhenCounty by grid GIS technology, then calculated the crop value of each grid and spreadGuzhen County agriculture exposure through statistical yearbook of Anhui Province.Calculated fragility curves of the wheat flood through historical statistics. At last, establishedagriculture flood disaster risk assessment model according to the concept of flood disaster riskmechanism, and then finish the agricultural flood disaster risk assessment of Guzhen by thegrid scale. The results show that: high risk and medium-risk staggered distribution alongHuihe river, medium-risk mainly exists in the southwest, Mopanzhang Town andWangzhuang Town, low-risk areas are located in the whole plains of the entire county. Thisresearch can provide an important thinking for disaster prevention and reduction.