河北平原区农田生态系统生产力稳定性及影响因子时序特征--以雄县为例

Stability of Farmland Ecosystem Productivity and Time-series Characteristics of Influencing Factors in Hebei Plain——A Case in Xiongxian County

生产力是农田生态系统的本质特征，为实现农田生态系统生产力持续稳定的增长，把握农田生产力的发展规律，研究农田生态系统生产力稳定性特征，分析影响农田生态系统生产力各因子的时间序列变化规律是十分必要的。论文以1974-2005年河北平原区雄县农村统计数据为依据，运用层次分析法计算农田生态系统生产力指数，采用剩余法剥离生产力波动趋势，从总体上研究农田生产力稳定性规律和时序分布特征；并进一步对影响农田生产力的6个因子波动特征进行比较分析，探索影响农田生产力稳定性的变化规律及其影响机制。结果表明，雄县农田生态系统生产力稳定性从总体上呈现分布比例均衡的趋势，在过去30年中基本处于稳定状态，作物生产供给基本平衡；生产力稳定性具有从不稳定向稳定发展的阶段性变化趋势；通过对生产力各影响因子的因子指数的波动特征分析发现，影响该区域农田生态系统稳定性的6个因子中，气候是波动因子，生产投入是稳定因子。

Productivity is the essential feature for the farmland ecosystem. It is necessary to study the stability of farmland ecosystem productivity and time-series dynamics of influencing factors to achieve sustainable and steady productivity development and to seize law of development of farmland productivity. Based on the statistical data of the years 1974 -2005 in Xiongxian County of Hebei Plain, the paper studied the stability of agro-produetivity and time-series characteristics. During calculation, the change of API （agro-ecosystem productivity index） was gained through the method of AHP （Analytical Hierarchy Process）, the agro-productivity waves was separated via residue method. In order to explore the impact mechanism and variety of agro-productivity stability, the time-series distribution and characteristics of influencing factors were analyzed. The results showed that ： （ 1 ） The ecosystem productivity of Xiongxian County was increased in the mass during the study period by analyzing of the productivity index. The fluctuation of agro-productivity could be divided into three phases, the mean amplitude of tide of agro-ecosystem productivity index was 0. 014, 0. 009 and 0. 003 at every phase. It can be said that the evolvement and development of farmland ecosystem productivity in Xiongxian County changed from instability to stability. （2） The proportion of harvest and lean year was the same as 21.86% in the total production vintage. It showed that distribution of farmland ecosystem productivity in Xiongxian County was balanced when viewed as a whole; and the agricultural productivity was in the warning line of monitoring stability while the fluctuation index was 0. 016. （3） Among the six factors which affect farmland ecosystem productivity stability in Xiongxian County, the fluctuation index of climatic had a large span, which could reach 0. 79. Thus it was a fluctuation factor. The input presented the great stability and the least fluctuation index, with an extent of fluctuation ranging between -0. 06 and 0. 05. Therefore, the input was a stable factor among the six factors.