1961~2010年中国农业洪旱灾害时空特征、成因及影响

搜集并分析了全国29个省份（不包括港、澳、台地区）1961~2010年农业洪旱灾害数据,深入探讨了中国洪旱灾害时空变异规律及其对粮食产量的影响。研究结果表明：中国大部分省份农业洪涝、干旱灾害具有明显的突变和趋势特征。中国中部、中西部及西北部洪涝灾害呈显著上升趋势;西北、东北地区及云南等地区干旱灾害呈显著上升趋势。除华北和东北地区外,洪涝灾害对农业的威胁日益严峻,而干旱灾害则无显著变化。这对中国粮食安全形成了重大挑战,尤其是西部以及北部地区粮食灾损率和灾损量显著上升。降水时空分布发生变化以及人类活动共同影响了中国农业洪涝、干旱时空变化特征。

Spatio-temporal Properties of Flood/Drought Hazards and Possible Causes and Impacts in 1961-2010

Data collection was done on flood/drought-induced loss of agricultural products and also crop fields from 29 provinces(municipality) in period of 1961-2010. Change properties were analyzed using trend test method such as Mann-Kendall trend test in this study to investigate spatio-temporal distribution of flood/ drought hazards and related impacts on agricultural productivity over China. The results indicated that: 1) Flood hazards are significant increasing trends in middle, mid-west and northwest parts of China. Evident increase of drought hazards, however, is observed in northwest, northeast parts of China and also in the Yunnan Province. In China except north China and northeast China, flood hazards have enhancing impacts and no evident negative impacts from drought hazards can be identified; 2) Abrupt changes of flood-affected and flood-damaged crop areas in the northeast, north and middle China are found mainly during 1980s and during 1990s in the south and southwest China. The abrupt changes of drought-affected crop areas however are detected mainly in 1984 and those of drought-damaged crop areas in south and north China are mainly in 1977 and 1984 in the middle and east China; 3) Spatio-temporal alterations of flood/drought hazards result in evident increase of hazard-induced loss and loss rate. Conspicuous impacts of flood/drought hazard on agricultural productivity can be detected in west and north China; 4) Increased seasonal precipitation amount and also the intensifying precipitation extremes give rise to increasing intensity and frequency of flood/drought hazards in northwest, southwest and middle China. Decrease of seasonal precipitation amount results in higher frequency of droughts in northeast and north China. This study is of great significance in planning and management of agricultural activities under the influences of climate change across China.