The Potential Distribution and Risk of Flood Waterlog on Cropland in the Middle-Lower Reach of Yangtze River in China (PAP014411)

Código

PAP014411

Autores

Youhao E, Zhiguo Huo, Fei Mao

Tema

Land use and Floods, landslides and erosion

Resumo

The floods waterlog on crop and farmland induced by heavy rainfall is one of the primarynatural disasters and has resulted in large number of food losses across the world. Flood submerge cropsin whole plants or part of the plants for long time, leading to the insufficiencies of oxygen in plant roots andlodging, resulting in decrease in production. In China, the average 9.42×106 ha of croplands were sufferedby flood waterlog every year with more than 1000 tons loss of food, while more than 55% of them occurredin the middle-lower reach of Yangtze River. With the increase in extreme rainfall events in future?s climatechange, it is very important to map the potential risk areas of flood waterlog induces by heavy rainfall toselect the flood resistant cultivars and manage the farmlands. In this paper, based on the data sets from 74meteorological stations in southeastern China during the periods of 1961 to 2008, the times of day of heavyrainfall that the daily precipitation were more than 50 mm, the largest daily precipitation of every stations,the largest continual precipitation of every stations and the probable distribution region of a heavy rainfallprocess were statistically analyzed and mapped by the GIS methods. And then, the fine resolution DEMextracted from the Yangtze River watershed and the vector land use map were add to analyze the potentialsinking areas using the Hydrology Model according to different probabilities of heavy rainfall (P = 1%, 2%and 10%). The results showed that the times of rainstorm and the largest daily precipitation, the largestcontinual precipitation and the spatial distribution of a rainstorm process distributed in the middle-lowerreach of Yangtze River with the distribution center area from Wuhan to Jiujiang. The potential risk croplandareas suffering severe and moderate flooding waterlog would be 650 (P=1%), 430 (P=2%), and 270(P=10%) ×104 ha respectively, approximately accounting for 28, 18 and 11% of the cropland areas in studyarea. The severe, moderate and slight flood waterlog area would be submerged cropland in 1.5 to 3.5 m,1.0 to 2.5 m and 0.5 to 1.5 m respectively.