广西元宝山南方红豆杉群落特征的研究

Studies on the phytocoenological feature of Taxus chinese var. mairei community in Yuanbaoshan, Guangxi, China

根据 16 0 0 m2 样方统计 ,群落区系组成有 4 3科 6 4属的 80个种 ,平均 10 0 m2 5种 ,虽种类组成不复杂 ,其中 87.5%的属仅出现 1种 ,6 .3%的属含少数种。乔木层多数优势种为稳定型种群 ,所以乔木层优势区系成分相当稳定 ,表明该群落为一种顶极群落。 59个种子植物属只有 10个分布区类型和 4个变型 ,地理成分不复杂 ,其中热带分布 2 7属占 4 6 .6 % ,温带分布 31属占 53.4 % ;热带分布以泛热带和热带亚洲分布为主 ,分别占 52 .6 %和 4 7.4 % ,温带分布为北温带和东亚分布各占50 %。 2 5个乔木层树种中 ,中亚热带地理分布类型的占 76 % ,南亚热带地理分布类型的占 16 % ,北亚热带地理分布类型占 8% ,重要值指数排列前 6名的均为中亚热带地理分布类型 ,所以该群落为亚热带性质。已知 79种组成种类常绿成分占 595% ,落叶成分占 4 0 .5% ,其中以中高位芽植物最多 ,占 2 7.8% ,又以常绿阔叶中高位芽植物为多 ,占 15.2 %。 79种组成植物 ,小型叶多于中型叶 ,分别占 55.7%和 32 .9%。乔木层种类 6 0 0 m2 有 18种 ,16 0 0 m2 有 2 9种 ,均不多 。

According to a statistics in 1 600 m 2 field of 7 samples, it is found that the specific composition in Taxus chinese var. mairei community is discomplex, for 80 species of 64 genera of 43 families compose the community flora, average 5 species in 100 m 2. However, it was almost composed of the genera with few species distributed in the community, in which 87.5% of the genera were found with one species only in the community and 6.3% of the genera contained few species. The results also showed that it was a climax community, as most of the dominant species in arborous layer were stable populations, so that the dominant elements of community floristic were stable. There were only 10 areal types and 4 sub types in 59 seed plants genera of which 27 belong to tropical genera, accounting for 46.6%, and 31 temperate genera, accounting for 53.4%, and tropical genera mainly constituted by pantropic (52.6%) and Trop. Asian (47.4%) and temperate genera mainly constituted by North temperate (50%) and E. Asian (50%). So that the geographical elements are discomplex. In the 25 species of arborous layer, 76% is the middle subtropical zonal type, 16% south subtropical zonal type and 8% north subtropical zonal type, of which the first 6 positions of important value index (IVI) were all middle subtropical zonal type. This showed that the community was subtropical characteristic. There are 59.5% evergreen and 40.5% deblade of 79 known species in which the mid phaenerophytes is the first position of all, accounting for 27.8%, and the evergreen broad leaved species constituted the majority of meso phaenerophytes which accounts for 15.2%. Meanwhile the number of Microphyll species (accounting for 55.7%) was more than that of Mesophyll one(accounting for 32.9%). There were 18 species constructed the arborous layer in sample of 600 m 2, and 29 species in sample of 1 600 m 2, the numbers were not large enough but the species diversity index approximately equaled to that index of standard community of subtropical zone. [WT5”HZ]