卧龙巴郎山川滇高山栎群落植物生活型海拔梯度特征

川滇高山栎林隶属于亚高山硬叶栎林类型,是一种广泛分布在横断山地区的特殊植被类型,研究同一群落生活型谱的海拔梯度特征,可以阐明控制群落的重要气候特征以及群落对其气候生境的反映,揭示川滇高山栎种群对空间的利用、群落内部种群间可能产生的竞争及其发展趋势。用环境梯度法,研究卧龙自然保护区巴朗山川滇高山栎群落植物生活型特性随海拔梯度(15个海拔梯度,海拔2200—3600 m)的变化。卧龙巴朗山川滇高山栎群落植物生活型以高位芽植物为主,占36.01%;地面芽和地下芽植物相当,分别为25.92%和29.36%,地上芽植物最少,占0.92%。高位芽生活型物种在各个海拔梯度都占重要地位,占巴朗山全部生活型物种的21.74%—50.00%,随海拔的升高逐渐下降;地面芽植物(H)具有随海拔升高先升高后降低的趋势;地下芽植物(G)生活型随海拔的升高而升高;一年生植物(Th)在整个海拔梯度内占10.00%以下,随海拔的升高波动不大,即在5.67%—8.94%之间。高位芽生活型植物主要以常绿高位芽植物为主,随海拔升高而下降,常绿高位芽植物丰富度呈现随海拔升高逐渐降低的趋势,而且其物种丰富度小于落叶高位芽植物丰富度;在卧龙巴郎山阳坡海拔3300 m以上范围内,大、中高位芽植物仅占3.09%—4.26%,说明森林植被特征在逐渐弱化。比较分析了不同类型植物群落植物生活型特征,阐明了川滇高山栎林是区别于其他常绿阔叶林的特殊类型。

Life-form characteristic of plants in Quercus aquifolioides community along an elevational gradient on Balang Mountain, Wolong Nature Reserve

Evergreen oak (Quercus aquifolioides Rehder & E.H. Wilson) forest is a type of subalpine sclerophyllous forest that is widely distributed in the subalpine zone of the Hengduan Mountains in southwestern China. In order to investigate the response of the forest''s plant life-form characteristics to climate environment, the adaptability of evergreen oak forest to space, and the possible competition among species, we documented the life-form characteristics of vascular plants from 15 different Q. aquifolioides communities along an elevational gradient from 2200 to 3600 m on Balang Mountain, Wolong Nature Reserve, SW China. The plant life forms of the community were mainly composed of Phanerophytes (36.01%), followed by Chamaephytes (25.92%) and Geocryptophytes (29.36%), and Hemicryptophytes were the least common (0.92%). Phanerophytes played an important role, accounting for 21.74% to 50% of all species living on Balang Mountain, although its prevalence gradually decreased with increasing altitude. In contrast, Hemicryptophytes initially increased with increasing altitude but then decreased, and Geocryptophytes increased with altitude. Meanwhile, the proportion of Therophytes fluctuated with increasing altitude, accounting for between 8.94% and 5.67% of the species present. In addition, the abundance of the evergreen Phanerophytes plants decreased with increasing altitude, and the richness of evergreen Phanerophyte species was lower than that of deciduous Phanerophytes. At 3300 m, the Macro-and Mesophanerophytes accounted for only 3.09% and 4.26% of the species present, respectively, this indicated that life-form characteristics of evergreen oak forest were gradually weakening. Finally, comparative analysis of the plant life-form characteristics of different plant communities indicated that the Q. aquifolioides forest is different from other special types of evergreen broad-leaved forest.