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在宁镇丘陵地区的句容市３个国营林场，选用广西融水优良种源，采用３３３０～１６６５０株／ｈｍ２的１１种初植密度营建杉木短轮伐建材林，探讨不同密度对椽材（小条木）和小径材生产的效应。结果表明，初植密度对树冠、胸径、树高、高径比、幼林蓄积、地上部份生物量及其分配均有显著的影响。但对幼林木材基本密度（６年）影响不明显。３３７０～５５５０株／ｈｍ２造林密度是该地区短轮伐期小径材作业适宜的初植密度，可望８年间伐椽材，１２～１４年生产出小径材。９９９０株／ｈｍ２以上密度不经间伐很难在８～９年生产出椽材，不宜作为椽材作业的初植密度。
Three national forest farms in Jurong, Ningxia hilly region were selected from the provenances of Guangxi Rongshui to construct the short-rotation Chinese fir plantation with 11 planting density of 3330 ~ 16650 plants / hm2. Strips wood) and the effect of small diameter wood production. The results showed that initial planting density had a significant effect on canopy, DBH, tree height, height to diameter ratio, young plantation accumulation, aboveground biomass and its distribution. However, the basic density of young forest timber (6 years) has no obvious effect. The planting density of 3370 ~ 5550 plants / hm2 is the suitable initial planting density for small-diameter timber operations in this area. It is hoped that the cuttings will be cut in 8 years and small-diameter timber will be produced in 12-14 years. 9990 / hm2 above the density is not difficult to cut in 8 to 9 years to produce rafters, rafters should not be used as initial planting density.