不同替代修复年限对飞机草种群和本土植物群落结构的影响

为研究替代修复对飞机草的治理效果以及对本地植物群落结构的修复效应，选择修复3、5、10 a和未修复（CK）的飞机草入侵生境为研究对象，调查飞机草密度、盖度、生物量、基径和本土植物群落的物种多样性、盖度等指标，采用“空间代替时间”的方法，分析不同修复年限飞机草种群特征和本地植物群落结构的变化.结果表明:①随着修复年限的增加，飞机草密度、盖度、基径、生物量等指标均呈显著降低趋势；修复10 a后，飞机草的盖度、密度、生物量、基径相比对照分别降低了97.3%、96.5%、98.6%、85.7%，飞机草入侵得到明显控制.②在植被替代修复过程中，飞机草入侵生境的群落结构得到明显改善，草本层物种多样性呈先升后降再升的趋势，草本层盖度在修复3 a后显著升高随后又显著降低，灌木层和乔木层物种多样性和盖度均呈显著增加趋势.研究显示，替代修复能有效治理飞机草入侵，促进植物群落的正向演替，提高本地植物群落结构的稳定性，增强生态系统对外来物种入侵的抵抗力. 

Effects of Different Replacement Restoration Years on Population of Chromolaena odorata and Native Plant Community Structure

In order to study the effect of replacement restoration on the control of Chromolaena odorata and the structure of native plant community, the habitats invaded by C. odorata with restoration for 3 years, 5 years, 10 years and non-restoration were taken as research objects. The density, coverage, basal diameter and biomass of C. odorata as well as the species diversity and coverage of native plant community were investigated. The method of 'space instead of time' was employed to analyze the changes in the population characteristics of C. odorata and the native plant community structure. The results showed that: (1) The density, coverage, basal diameter and biomass of C. odorata decreased significantly with the increase of restoration years, and decreased by 97.3%, 96.5%, 98.6% and 85.7%, respectively, compared with the control after 10 years restoration. The invasion of C. odorata was obviously controlled. (2) The plant community structure of the habitats invaded by C. odorata was significantly improved during the process of plant replacement restoration. The species diversity of herbaceous layer increased first, then decreased and then increased again. The coverage of herbaceous layer increased significantly after 3 years restoration and then significantly decreased with the increase of the restoration years. The species diversity and coverage of shrub and tree layers increased significantly during the restoration process. The study has shown that replacement restoration can effectively control the invasion of C. odorata, improve the stability of the native plant community structure, promote the positive succession of plant community, and strengthen the resistance of ecosystem to invasion by alien species.