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在水杉人工林内设立标准地，定量机械间伐，定期测定生长量，对其抚育间伐效果及经济效益进行分析，结果表明：（１）不同初植密度的林分采用较小的强度Ｐｎ＝２５％、３３％进行间伐，与对照林分相比，平均每公顷生长量分别提高５．９７ｍ３、９．２７ｍ３，增加９．５７％、１４．８７％；采用较大强度Ｐｎ＝５０％进行间伐，与对照林分相比，平均每公顷生长量下降９．７ｍ３，减少１５．５７％。（２）抚育间伐过的林分（间伐强度Ｐｎ＝２５％、３３％、５０％）与对照林分相比，单位面积保留木平均生长率分别提高１．３４％、２．００％、１．９７％。（３）抚育间伐的林分与对照林分相比，平均每公顷总产值和利润分别增加６２７８元、５７８４元，增长７．７％、９．５％。
In the metasequoia plantation set up a standard, quantitative mechanical thinning, regular measurement of growth, its tending thinning effect and economic benefits analysis, the results showed that: (1) different planting density of the forest with a smaller intensity Pn = 25% , 33% respectively. Compared with the control stand, the average growth per hectare increased by 5.97m3 and 9.27m3, increased by 9.57% and 14.87%, respectively. Compared with the control stand, thinning was carried out with the higher intensity Pn = 50% Compared with the control stand, the average growth per hectare decreased 9.7m3, a decrease of 15.57%. (2) Compared with the control stand, the average growth rate of reserved wood per unit area increased by 1.34%, 2.00% and 1% respectively in thinning stand (thinning strength Pn = 25%, 33%, 50% .97%. (3) Compared with the control stand, the average yield per hectare and profit increased by 6,278 yuan and 5,784 yuan respectively, up by 7.7% and 9.5% respectively.