东北农牧交错带旱涝特征对气候变化的响应

目的]从旱涝灾害角度分析气候变化对东北农牧交错带的影响,对该区的气候变化和旱涝特征进行研究,为充分利用气候资源,合理调配水资源,提高灾害应变能力提供科学依据。方法]统计1960—2011年东北农牧交错带21个气象台站的逐月气温、降水资料,应用Mann—Kendall气候突变检验法、标准化降水指数(SPI)、样条函数插值法对该带旱涝状况的时空分布进行了分析。结果](1)东北农牧交错带气候呈现出明显的暖干化趋势,SPI3表明春、夏、秋三季干旱事件增多,21世纪以来,春旱事件较为频繁,冬季降水略微增加;(2)气温突变发生在1988年,突变后,干旱的比例增加了20.7%,涝的比例增加了9.3%,降水处于"正常"的年份则大幅度减少,对该区极为不利;(3)SPI12低值中心由科尔沁沙地向东北延伸到松嫩平原,干旱面积有大幅度增加的趋势,东北农牧交错带中南部旱化较为严重。结论]东北农牧交错带暖干化的趋势给该区农牧业带来不利影响,受旱地区应及时启动干旱预警紧急方案,开展抗旱工作。

Droughts and Floods Response to Climate Change in Agro-pastoral Ecotone of Northeast China

Objective] This paper analyzed the characteristics of drought and flood disasters occurred in agro-pastoral ecotone of Northeast China and the precedent climate change, mainly from the view of the effects of climate change on drought and flood disasters, in order to provide the scientific basis for making full use of climate resources, allocating water resources reasonably and improving response capacity to disaster.Methods] Using the monthly temperature and precipitation data of 21 stations in agro-pastoral ecotone of Northeast China from 1960 to 2011, this paper analyze the temporal and spatial distribution of drought and flood conditions by Mann-Kendall climate mutation test, the standardized precipitation index(SPI), splining interpolation method.Results] (1) The area showed a tendency of warming and drying. SPI3 showed that flood events increased in spring and winter, while in summer and autumn drought event increased; (2) The temperature changed in 1 988 suddenly. After the mutation, drought increased at a proportion of 20.7%, flood rised in a proportion of 9.3%. Precipitation in the "normal" year reduced significantly, this is extremely unfavorable to the area; (3) Regions with low value center of SPI extended from Horqin sandy land to the Songnen Plain in the northeast area, drought was more serious in the middle and south of the agro-pastoral ecotone of Northeast China.Conclusion] The ecological environment of this area seems vulnerable, in order to offset the negative influence of warming and drying on farming and animal husbandry, emergency plan should be started early in drought areas.