Abstract: Based on logarithmic mean weigh division index method (LMDI), empirical mode decomposition method (EMD) and variance decomposition model (VDM), the evolutive trend and fluctuation characteristics of corn production in China during 1978–2012 was analyzed. The contribution difference to corn output fluctuation during eight grain production regions was revealed. The following results were obtained. Corn output increased by 1.50×10⁸ ton from 1978 to 2012, and the corn production advantage in Huang-Huai-Hai region and Northeast Region in China was further highlighted. It was estimated that the accumulated contribution values of corn sowing area and corn yield per hectare at national scale were 0.79×10⁸ ton and 0.71×10⁸ ton respectively, and corn sowing area was the major contributor to the increment of corn output. The residual trend of corn output showed a trend of gradual increase and the grain output has 3-year periodic oscillation. During the eight grain production regions in China, Huang-Huai-Hai Region played the prominent role in the total fluctuation, following by the Northeast Region and Loess Plateau Region. The self-fluctuations in the three regions and their positively mutual affect were the main factors of China’s corn output fluctuation, including Huang-Huai-Hai Region, Northeast Region and Loess Plateau Region in China. For the high contribution ratio and drastic change, more attention should be paid to Huang-Huai-Hai Region and Northeast Region in China.

Key words: corn output, evolutive trend, fluctuation characteristics, logarithmic mean weigh division index method, empirical mode decomposition

摘要： 采用对数平均迪氏分解模型(LMDI)、经验模态分解模型(EMD)和方差分解模型(VDM), 系统分析 1978—2012 年中国玉米产量的变化趋势和波动特征。结果表明, 35 年间玉米产量增加1.50×10⁸ t, 东北区和黄淮海区的玉米生产优势进一步凸显; 玉米播种面积效应和玉米单产效应分别为0.79×10⁸ 和0.71×10⁸ t, 播种面积是中国玉米产量快速增加的主要因素。玉米产量以趋势增长为主, 且存在3 年左右的准周期波动, 玉米单产波动是准3 年周期波动的主要影响因素。从八大粮食产区看, 黄淮海区玉米产量的波动量最大, 其次为东北区和黄土高原区; 黄淮海区、东北区和黄土高原区自身的产量波动及其相互间的正向联动作用是中国玉米产量波动的主要因素; 黄淮海区和东北区的玉米产量波动量大且变化剧烈, 应重点关注这两个区的玉米生产。

关键词: 玉米产量, 变化趋势, 波动特征, LMDI 模型, 经验模态分解模型