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杉木林不同间伐强度试验的定位观测分析结果表明，不同间伐强度对胸径生长的影响达到显著差异，对树高生长的影响差异不显著；不同间伐强度能提高林分单株材积和经济出材率；但不能提高单位面积产量。经济效益分析表明，不同间伐强度的经济效益以中度间伐为最高，净现值比对照提高２７％，内部收益率提高２．２％，每公顷增加收益１３５６元；其次是强度间伐，净现值比对照提高２５％，内部收益率提高１．２％，每公顷增加收益１２４８元。
The results of the location observation and analysis of the different thinning intensity tests of Chinese fir plantation showed that the effects of different thinning intensities on the DBH growth were significant and the differences were not significant for the tree height growth. Different thinning intensities could improve the stand volume per plant and economic yield ; But can not increase yield per unit area. Economic benefit analysis shows that the economic benefits of different thinning intensities are the highest among moderate thinning, the net present value is increased by 27% compared with the control, the internal rate of return increased by 2.2%, and the yield increased by 1356 yuan per hectare; secondly the intensive thinning, 25% higher than the control value, the internal rate of return increased by 1.2%, an increase of 1248 yuan per hectare yield.