平原农区,光热水资源丰富,人口稠密,人均土地面积少,生态环境差,木材缺乏。在三边(路边、渠边、村边)等隙地建设农田防护林,不仅能改善生态环境,还可生产木材及林副产品。但设计什么结构的林带,生产木材较多较好?防护效益最佳?带着这个问题,对望都县的农田林网进行了调查。 Plain agricultural areas, light and hot water is rich in resources, densely populated, per capita land area is small, poor ecological environment, lack of timber. The construction of farmland shelterbelts on three sides (curb, canal side and village side) will not only improve the ecological environment but also produce wood and forest by-products. But what structure of the design of the forest belt, the production of wood is more good? Protection of the best? With this problem, Wangdu farmland Lin Wang conducted a survey.