棉田生态系统能流经济阈值的初步研究

PRELIMIN ARY STUDY ON THE ECONOMICAL THRESHOLD OF ENERGY FLOW IN COTTON FIELD

系统能流经济阈值（ＥＥＴ）为本项研究提出的新概念。它是指系统的初级生产者─—作物向其它亚系统输出能量的允许临界值，由此产生的期望收益最大。系统能流经济阈值是一条仅与作物现存量相关的动态曲线，与其他亚系统无直接关系。本文以未施药棉田为系统，提出能流经济阈值的研究方法为：建立能流动态模型；确定害虫防治代价，计算期望产出；运用计算机仿真语言对作物的能流输出参数进行优化并建立系统能流经济阈值模型。

new idea concerning economical threshold of energy flow(EET)was advanced.EETis meant by that the energy flowed out of the crop to the subsystem of pest amounts to suchan extent of allowable threshold,as a result that the economic gains should be the maximum.The EET,relating only to standing-corp of producer,shows a dynamic curve.In this paper,regarding the cotton field without appling insecticides as an object of system,a program wasput foward for researching EET:to construct the models of energy flow in this system;to de-termine the cost,spending on pest control and to estimate the expecting yield;to get optimumparameter and finally to result in EET model on completion.