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杨树是我区农田林网的主栽树种,但是数年来营造的杨树林带植距过小,林木生长不良,病虫害严重,影响了防护效益的发挥和木材的产量、质量,为找出合理植距,近几年对生长和管护较好的农田防护林进行了调查观测,现将结果整理如下:一、调查概况数据主要取于枣强县老官里大队定植4年及安平县南大良大队定植7年的大关杨林带。两地均属黑龙港流域,地势平坦,砂壤土,
Poplar is the main species of farmland forest net in our district, but the planting of poplar forest belt over the past few years is too small, poor growth of trees, serious pests and diseases, affecting the protection efficiency and the yield and quality of timber, in order to find out the reasonable In recent years, investigation and observation of farmland shelterbelt with better growth and management and maintenance has been carried out. The results are summarized as follows: I. Survey Survey Data are mainly taken from the planting of Laoguanli Brigade in Zaoqiang County and Nan Da Liang of Anping County Brigade planting seven years mark Yang Lin belt. Both belong to the Heilongjiang River Basin, flat, sandy loam,