太白山太白红杉林数量分类
Classification and Ordination of Larix chinensis Communities in Mt. Taibai

太白红杉(Larix chinensis)是秦岭特有物种和高山林线树种，主要集中分布在太白山，是国家保护物种。结合数量分类和排序方法分别对太白山南北坡太白红杉林进行分类，北坡共划分为5组，分别是太白红杉-牛皮杜鹃(Rhododendron aureum)+头花杜鹃(Rhododendron chrysanthum)-苔草(Carex sp)+乌头(Aconitum carmichaeli)群落，太白红杉-头花杜鹃+杯腺柳(Salix cupularis.)+高山杜鹃(Rhododendron lapponicum)-莎草(Cyperus rotundus)+苔草群落，太白红杉-高山杜鹃+陕甘花楸(Sorbus koehneana)+头花杜鹃-苔草+糙苏(Phlomis umbrosa)群落，太白红杉-陕甘花楸+峨眉蔷薇(Rosa omeiensis)-苔草群落，巴山冷杉＋太白红杉-牛皮杜鹃群落；南坡共划分为4组，分别是太白红杉-小叶忍冬+茶镳子(Ribes spp.)-莎草+风毛菊(Saussurea japonica)群落，太白红杉-高山柳+陕甘花楸+头花杜鹃-莎草+银莲花(Anemone cathayensis)+碎米荠(Cardamine hirsuta)群落，太白红杉-小叶忍冬+头花杜鹃-苔草+风毛菊群落，巴山冷杉＋太白红杉群落；此外，阐述了各类太白红杉林的群落特征（太白红杉种群特征、林下物种组成、盖度和高度）和生境特征（分布海拔、坡度、温度和降水）。本文对太白红杉林的分类及其群落特征描述可为科学保护、合理经营太白红杉林提供科学依据。
Larix chinensis is an endemic species in Mts Qinling and a national protected species. It is timberline trees and mainly concentrated in the Taibai Mountain. In this paper, we used quantitative classification and ordination methods to classify L. chinensis communities on southern and northern slopes of Mt. Taibai, respectively. Then we described the characteristics of various types of L. chinensis communities, including the characteristics of L. chinensis populations and the composition, cover and height of understory species. And we described the habitat characteristics, including elevation, slope, temperature and precipitation. The results showed that L. chinensis communities on the northern slope based on understorey species composition and dominance. L. chinensis communities on southern slope were divided into five groups. L. chinensis communities on southern slope were divided into four groups. Classifying of L. chinensis communities and describing their community characteristics of different groups can provide a scientific basis for conservation, management of this endangered species