文峪河上游河岸林群落类型及其生态适应性

以文峪河上游河岸林为研究对象,采用TWINSPAN法对研究地区河岸林进行群落分类,对各群落类型特征进行分析.在提出河岸林群落生态功能适应性指标的基础上,对研究地区河岸林群落进行生态功能适应性分组.通过研究,文峪河上游河岸林可划分为阔叶混交林、华北落叶松阔叶混交林、云杉落叶松混交林、云杉阔叶混交林、阔针混交林、油松阔叶混交林、青杨林、沙棘灌丛和柳树灌丛等9个群落类型,但群落类型之间的分异性总体表现不高,且表现出突出的多样性特征;群落乔木层和灌木层的物种组成复杂,草本层多为一些耐干扰种和耐水湿种,总体上越远离河岸,高地群落中的物种比例越高,表现出高地森林与河流之间生态过渡带的典型特点和河岸带生态环境的高度异质性;根据本文构建的群落的生态功能适应性指标,研究地区9个河岸林群落类型可以划分为强入侵性功能组、中等入侵性功能组、弱入侵性功能组和高逃避性功能组等4个生态适应性功能组,不同生态适应性功能组的群落中,乔木层和灌木层的主要物种具有明显不同的生态对策,而草本层物种的差异不明显.

Community types and ecological adaptation characteristics of the riparian forest in upper reach of Wenyuhe Watershed

This study was conducted on riparian forests in the upper reach of Wenyuhe watershed. The community types were classified by the method of TWINSPAN. The community characteristics and diversity were also analyzed. We proposed the eco-functional adaptation indices of the riparian forest communities, based on which the riparian forests were divided into different functional groups. The riparian forests in the upper reach of Wenyuhe watershed were classified into 9 community types: broad-leaved mixed forest, Larix principis-rupprechtii + broad-leaved mixed forest, Picea meyeri + Larix principis-rupprechtii mixed forest, Picea meyeri + broad-leaved mixed forests, broad-leaved + needle-leaved mixed forest, Pinus tabulaeformis + broad-leaved mixed forests, Populus davidiana forest, Hippophae rhamnoides bush and Salix bush. The differences between these types were not very significant, but the diversity was obvious. The species composition of tree and shrub layers were complicated and various, and the species of herb layer were often disturbance-tolerant and humidity-tolerant ones. Generally, the far away from the river bank, the more species of alpine community appeared which was the typical characters of ecological transition zone between the alpine forest and river bank, and was also closely related with the spatial and temporal heterogeneity of riparian zone. According to the eco-functional adaptation indices, the riparian forests were divided into four eco-adaptation functional groups, i.e. the strong invasion group, the intermediate invasion group, the weak invasion group and the strong avoiding group. The eco-strategy of tree layers and bush layers were significantly different from each other among the four groups, but the differences of the herb layers were not significant.