黄土高原弃耕地不同地形下植物群落演替初期的群落结构及多样性研究

采用样方调查方法对不同地形下典型黄土高原弃耕地植物群落发育初期阶段的植物群落物种组成及其相似性和多样性进行了研究。结果表明,不同地形下弃耕地植物群落演替初期的植物生活型结构不同,主要体现在以地面芽植物或一年生植物居多。植物群落演替初期坡顶和阴坡的群落相似性较大,而阳坡和坡底植物群落相似性较大。不同地形下植物群落多样性有差异,群落均匀度差异较小,各个多样性指数在不同地形的群落间的差异显著性不同,综合多个多样性指数值的大小,坡顶的植物群落多样性最大,而阳坡植物群落多样性最小。笔者推测,未来几年坡顶植物群落和阴坡植物群落将向多年生植物群落方向演替,而坡底和阳坡将向一年生植物群落方向演替。建议弃耕地植物群落学特性研究应长期进行,以便为黄土高原植被恢复和重建提供更加科学的依据。

Studies on diversity and structure of plant communities in early succession stage in abandoned land at different landforms on the Loess Plateau

The species component, similarity, diversity of plant communities at early succession stage in abandoned land at different landforms on the Loess Plateau were studied by sampling methods. The results showed that the structure of plant life forms was different among landforms and the number of hemicryphtophytes or annual plants were more than others. The similarity of top slope communities to north-facing slope communities was higher and it was in the same situation between south-facing slope and bottom slope. There were certain differences at community diversity among different landforms, and the differencs of community evenness were not significant. The significant level of diversity differencs with four different landforms were dissimilar, the diversity of top slope was the highest, and the south-facing slope the lowest. It could be concluded that, the plant communities of top slope and north-facing slope would develop toward perennial plant communities, and the plant communities of bottom slope and south-facing slope would develop toward the annual plant communities in the future. Therefore, the ecological characteristics of abandoned land needed to be studied in longterm, and this might provide more scientific foundations for the vegetation restoration and rehancement on the Loess Plateau.