巴郎山川滇高山栎群落植物科组成的海拔梯度特征

Characteristics of Plant Family Composition of Quercus aquifolioides Community along an altitude Gradient on the Balang Mountain

川滇高山栎林是中国植被非常特殊的亚高山硬叶栎林类型,广泛分布在横断山地区。为了阐明川滇高山栎群落植物科组成对海拔梯度的响应,用群落学调查方法研究了组成群落的植物科沿海拔梯度(15个海拔梯度,海拔2 200 m^3 600 m)的变化特征。研究结果表明:巴郎山川滇高山栎群落植物科的分布区类型,有世界分布31科、热带分布21科和温带分布21科,分别为占42.47%、28.77%和28.77%。川滇高山栎群落的植物科数具有低海拔比高海拔多的特点,在海拔3 100 m以上,分布的植物科数没有变化。在各个海拔梯度以世界分布科占主要地位,其次为热带分布科和温带分布科。热带分布科随海拔的升高具有递减的趋势,温带分布科随海拔的升高出现2个峰值。在海拔2 200 m^2 800 m范围,热带分布科和温带分布科相当,海拔2 900 m以上,温带分布科明显增多。

The evergreen oak（ Quercus aquifolioides Rehder E. H. Wilson） forests are widely distributed in the subalpine zone on the Hengduan Mountains,southwestern China. In order to understand the response of plants to the elevational gradient,studies were made of the plant family composition of Q.aquifolioides community from 15 different sites along an elevational gradient from 2200 to 3600 m. a. s. l.on the Balang Mountain,Wolong Nature Reserve,SW China. The distribution types of Q. aquifolioides community included the world distribution of 31 families,21 families of tropical distribution and 21 families of temperate distribution,respectively,accounting for 42. 47%,28. 77% and 28. 77%. The number of plant families in Quercus aquifolioides communities at low altitudes was more than that at high altitudes.Above 3100 m. a. s. l.,the distribution of the number of plant families did not changed. The world distribution families were dominant in each altitudinal gradient,followed by families of tropical and temperate distributions. Tropical distribution families had a decreasing trend with the increasing altitude,temperate distribution families exhibited two peaks with the increasing altitude. From 2 200 m to 2 800 m,tropical and temperate distribution families were basically the same. Temperate distribution increased significantlyabove 2 900 m. a. s. l..