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洞庭湖流域为我国重要农业生产区,而农业水灾却一直是制约农业可持续发展的最大障碍因素。以1950—2009年水灾统计资料为依据,用定性与定量相结合的方法,系统分析了该流域农业水灾演变特征及区域分异。结果表明:①年年发生流域性或区域性的农业水灾,其中重灾、特大水灾频率呈增大趋势;②在长时间尺度演变过程中,受灾率异常指数岀现2个波峰期和4个波谷期,成灾率异常指数岀现3个波峰期和3个波谷期,且水灾受灾率与成灾率大体上呈同步变化,但短时间內受灾率与成灾率却呈反向波动;③农业水灾具有突变性,但总体演变呈增加趋势;④受孕灾环境、洪涝致灾因子及经济发展水平组合差异的制约,农业相对灾情与绝对灾情在空间上的分布均呈明显的南北分异与东西分异。
Dongting Lake basin is an important agricultural production area in China, but agricultural flood disaster has always been the biggest obstacle to the sustainable development of agriculture. Based on the statistics of floods from 1950 to 2009, the characteristics and regional differences of agricultural floods in the basin were systematically analyzed by qualitative and quantitative methods. The results show that: (1) annual or regional agricultural floods occur, of which heavy disasters and extra-large floods tend to increase. (2) During the long-term evolution, the anomaly index of disaster anomaly is at 2 peaks and 4 The tidal wave and anomaly rates of anomaly index are at 3 peak periods and 3 trough periods, and the flood disasters rate and disastrous rate change in general, but the disasters rate and disastrous rate fluctuate in short time. (3) Agricultural floods have mutation, but the overall evolution shows an increasing trend; (4) Due to the difference in the combination of pregnancy disaster environment, flood and flood hazard factors and economic development level, the spatial distribution of relative disaster and absolute disaster in agriculture shows obvious north-south differentiation Differentiate with something.