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本文研究了自然林下和深入林内２ｋｍ新开公路的斜坡（当作特殊的林窗）的幼苗的种类组成、多样性、分布格局和生长。林下幼苗种的丰富度（９９种）和Ｓｈａｎｎｏｎ－Ｗｉｅｎｅｒ多样性指数（５．４３）与所在林分立木种的丰富度（１１７种）和多样性指数（５，４２）相当，而比公路斜坡相近面积上幼苗的相应值（５９种，多样性指数４．２１）高。林下幼苗的乔木种类占的比例（４６％）较公路斜坡幼苗的乔木种类的比例（３４％）高，而草本种类占的比例（２３％）较后者（３２％）低。林下幼苗的木本种类和林分立木的Ｓφｒｅｎｓｅｎ相似系数（０．５００）较公路斜坡幼苗木本种类和林分的相似系数（０．１７１）高得多、林下幼苗的种类组成和公路斜坡幼苗的种类组成的相似性很低（Ｓφｒｅｎｓｅｎ系数０．２４７）。两个生境中大多数优势种群都表现为集群分布。公路斜坡上的幼苗种群似乎集群程度更高。先锋树种的幼苗在公路斜坡较瘦瘠的土壤条件下，１～５年生幼苗的平均相对生长率为：０．９４４～１．５５５ｇ·ｇ－１·ａ－１，比在林下耐阴树种幼苗的相对生长率（０．７６５～１．４０２）高或相当，但生物量积累较后者慢。在森林中，耐阴树种的幼苗未显出休眠的特性。先锋树种的幼苗有较高比?
This paper studied the species composition, diversity, distribution pattern and growth of seedlings under the natural forest and on the slope of 2km newly opened highway in the forest, which is regarded as a special canopy gap. The richness (99 species) and Shannon-Wiener diversity index (subslice) of understory seedlings are comparable with the richness (117 species) and diversity index (5,42) The corresponding values (59 species, diversity index 4.21) of the seedlings in similar area on the slope were high. The percentage of undergrowth tree species (46%) is higher than that of roadside seedlings (34%), while the proportion of herbaceous species (23%) is lower than the latter (32%). The Sφrensen similarity coefficient (0.500) of tree species and stand standing wood of seedlings under shelterbelts was much higher than the similarity coefficient (0.171) of woody woody species and stand of hillside seedlings. The species composition and highway The similarities in the species composition of the slope seedlings are very low (Sørensen coefficient 0.247). Most dominant populations in both habitats showed cluster distribution. The population of seedlings on road slopes seems to cluster more. Pioneer tree seedlings in the road slopes of relatively barren soil conditions, the average relative growth rate of 1 to 5-year-old seedlings: 0.944 ~ 1.555g · g-1 · a-1, than in understory shade trees The relative growth rate of seedlings (0.765 ~ 1.402) is high or equivalent, but the biomass accumulation is slower than the latter. In the forest, shade-tolerant seedlings did not show dormancy characteristics. Pioneer tree seedlings have a higher ratio?