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二十年来的实践证明,凡是农田防护林已构成一个防护体系,基本实现农田林网化的社、队,对防风固沙,蓄水保土、保肥,改善农业生产条件,提高产量等方面,都起到了较为明显的作用。但是,据调查目前已营造起来的农田防护林有的网格过大,网内的农田不能全面受益;林带有的过宽,不仅增加了占地比率,也相对的降低了防护效应。为了改变这种局面,我们对农田防林网格大小及林带宽度进行了观测研究。现将研究的结果归纳分析如下:
Practice over the past two decades has proved that all the farmland shelterbelts have constituted a protective system and basically realized socialization and teamwork of farmland shelterbelts with regard to windbreak and sand fixation, water conservation and soil conservation, fertilizer conservation, improvement of agricultural production conditions and increase of production Played a more obvious role. However, according to the survey, the number of grids of farmland shelterbelts that have been constructed so far is too large to fully benefit farmland in the network. Too much forest belt not only increases the occupation ratio, but also reduces the protective effect. In order to change this situation, we observed and studied the size of farmland anti-forest grid and the width of forest belt. Now the research results are summarized as follows: