中国农作物成灾面积的演化趋势及波动特征研究

Evolution trend and fluctuation characteristics of disaster affected crop area in China

综合运用经验模态分解法、剩余法和方差分解法,系统分析了1978—2012年中国农作物成灾面积的演化趋势、波动特征及引起成灾面积波动的灾害类型差异和地区差异,旨在为中国农业生产防灾减灾提供科学依据。结果表明:(1)农作物成灾面积"先增后降",旱灾和水灾是主要灾害类型;成灾面积主要分布在长江中下游区,黄淮海区和黄土高原区。(2)农作物成灾面积的波动特征明显,存在3a和8a左右的准周期波动。(3)在灾害类型上,旱灾和水灾成灾面积波动的总方差贡献为91.77%,是中国农作物成灾面积波动的主要灾害类型。(4)从八大粮食产区看,长江中下游区农作物成灾面积波动的总方差贡献率最大,其次为东北区和黄淮海区,应重点关注这几个地区的成灾面积变化和波动。

Based on empirical mode decomposition method, residual method and variance decomposition model, the evolutional trend and fluctuation characteristics of crop area affected by natural disaster in China during the period 1978 -2012 were analyzed firstly, and then the difference of the contribution to crop disaster area fluctuation be- tween natural disaster types and between grain production regions were revealed. The following results were ob- tained： （1） the crop area affected by natural disaster increases first and decreases afterwards, and drought and flood are the main disaster types. Crop area affected by natural disaster is mainly located in the middle - lower reach region of the Yangtze River, the Huang - Huai - Hai region and Loess Plateau Area. （2） Crop area affected by natural disaster shows significant fluctuation characteristics with 3 - year cycle and 8 - year cycle. （3） The total variance contribution rate of flood and drought in the total fluctuation is 91.77%, so they both are the main - con- trol disaster types for the fluctuation of crop disaster area in China. （4） Among the eight grain production regions in China, the middle - lower reach region of the Yangtze River play the prominent role in the total fluctuation, following by the northeast region in China and then the Huang- Huai -Hai region, more attention should be paid tothe disaster-affected crop area change and fluctuation of these regions..