典型农业生态工程运行机制分析—以山东省西单村为例

通过对典型农业生态工程结构的研究，分析了生态农业系统的运行机制，结果表明，结构多样性与主导性关系的协调问题，是目前制约农业生态系统良性循环的根本问题，山东省西单村农业生态系统之所以以前期能够保持持续稳定发展，后期出现减缓趋势，主要原因也是由于其系统的结构多样性比较高，结构多样性指数最高达0．6556，结构链内部各组分之间的协调性超过90％，而系统实际主导性则较低，结构主导性指数最高为0．2574，系统的最高协调性指数只有0．1327，因此，要保证系统的可持续发展，必须保证系统结构的协调性。

Running mechanism of a tvpical agricultural eco-engineering model - Taking Xishan village as an example.

The prerequisite for an agricultural ecosystem that wants to be run benignly is its structural diversity, while the major dynamics is the structural dominance.This paper dealt with the running mechanism of agricultural eco engineering (A EE ) by analyzing the structure of a typical AEE model in Xishan village, Shandong P rovince. The harmony between structural diversity and dominance is considered as one key issue for good function of an agroecosystem. The important reason that the agroecosystems in Xishan village have developed sustainably in a long term, w ith a tendency of slowing down its speed recently, is the harmony between struct ural diversity and dominance. The structural diversity index has kept in a high level for a long time with the highest 0.6556, and harmony among components in d ifferent structural chains is all over 90%. Meanwhile, the dominance index has k ept in a low level with highest 0.2574, and the highest harmony index is only 0. 1327. It is suggested that the system structure harmony should be maintained in order to guarantee the sustainable development of AEE.