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通过对甘南县音河乡农田防护林带的主要树种有(盛) 叶期与无(枯) 叶期的疏透度观测, 得出落叶的杨树林带, 落叶松林带有、无叶期的疏透度变化较大, 变化率大于100% ;常绿的樟子松林带盛、枯叶期的疏透度变化较小, 变化率不到15% 。研究结果表明了“以松改杨”的农田林网优化的必要性和可行性。
Through the observation of the main tree species of farmland shelterbelts in Yinhe Township of Gannan County, the leaf density of the major tree species in the field of shelterbelts was compared with that of the non-leaf stage, the deciduous poplar forest belt, The change of permeability is larger, the rate of change is more than 100%. The evergreen Pinus sylvestris var. The result of the research shows the necessity and feasibility of optimizing farmland network of forest by “Replacing Song with Yang”.