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农田防护林是防护林体系的主要组成部分,是人类改造自然的重要生物工程。它的功能具有多样性和稳定性。所谓多样性,是指通过林带的动力作用,对气流的阻挡、抬升、分割,改变气流的结构,影响水分、热量的分配,从而发挥热力效应、水文效应、生物效应、土壤改良效应,达到提高农业效应的目的。林带本身又是再生的绿色资源。所谓稳定性,指其多种效益具有长期性和稳定性。以杨树为主的农田防护林,其防护成熟龄一股为15—20年。营造针阔混交或针叶树林带,防护成熟龄还可以延长。农田防护
Farmland shelterbelts are the main components of the shelterbelt system and an important bioengineering project for mankind to transform nature. Its versatility and stability. The so-called diversity means that the dynamic effect of forest belt can block, lift and divide the air flow, change the structure of the air flow and affect the distribution of moisture and heat so as to exert the heat effect, hydrological effect, biological effect and soil improvement effect The purpose of the agricultural effect. Belt itself is a renewable green resource. The so-called stability refers to its long-term stability and a variety of benefits. Poplar-based farm shelterbelts, the protective maturity of a 15-20 years. Coniferous and coniferous forests or conifers to create, protective maturity can also be extended. Farmland protection