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位于三江平原中部的宝泉岭国营农场管理局,七十年代以来营造以杨树为主的农防林近10万亩.该地区属于半干旱半脊薄的立地条件,年降水量平均450mm左右.土壤大部分为暗棕壤和白浆土,有机质含量低在1-3%.五百万亩耕地上的农防林网是逆转目前垦区农田生态环境恶化的主要生物措施,是改善农田水、热、风、湿、温性状的重要链条.是农田高产稳产、建立良好的现代化大农业生态体系的重要保证.经考察发现:农田防护林由于初植密度过大,土壤贫脊,生长季节水分缺乏.生长速度缓慢.通
The Baoquan Ridge State Farm Authority, located in the middle of the Sanjiang Plain, has built nearly 100,000 mu of poplar-dominated agricultural and forestry-protected forests since the 1970s. The area belongs to semi-arid and semi-ridges site conditions with an average annual rainfall of about 450 mm . Most of the soil is dark brown soil and albic soil, with low organic matter content of 1-3% .In five million mu of arable land, the forest and forest network is the main biological measure to reverse the deterioration of the ecological environment in the reclamation area and to improve the farmland water , Heat, wind, wet, temperature properties of the important chain is high and stable yield farmland, to establish a good modern large-scale agroecosystem important guarantee.After investigation found that: farmland shelterbelts due to the initial planting density is too large, the soil ridges, the growth of seasonal water Lack of growth slow