关键词: 白符跳, 存活率, 转基因大豆, 繁殖率, 体长

Abstract: Understanding changes in species composition, community structure and biodiversity during natural vegetation restoration can provide important basis for the selection of tree species and the optimization of community structure in artificial vegetation restoration. In this study, different natural vegetations (herbosa, shrub and forest) in Jianshui County of Yunnan, a typical area of karst graben basin, were phytocoenologically investigated using the method of space substitutetime. Plant communities were stratified into tree, shrub, and herb layers at different restoration stages. The species composition, horizontal and vertical structure, and biodiversity of plant communities at different restoration stages were analyzed. The results showed that a total of 94 vascular plant species belonging to 43 families and 72 genera were recorded in 12 plots with a total area of 3200 m². Dominant species were mainly from Fagaceae,Rhamnaceae, Myrsinaceae, Rosaceae, and Oleaceae. During the herbosa shrubforest restoration, the number of families, genera, and species in community composition increased, the proportion of short and smallstature individuals decreased, but the whole community was still dominated by short and smallstature individuals. Richness and Shannon index of herbaceous plants were the highest in the early stage of vegetation restoration, i.e., the herbosa stage, while evenness was the highest in the shrub stage. Richness and Shannon index of woody species increased gradually with vegetation restoration, but evenness decreased gradually with vegetation restoration. With vegetation restoration, the ecological dominance of herbaceous layer and tree layer increased and that of shrub layer decreased. The herbaceous plants changed from the early annual or perennial herbs which were heliophilous, droughtresistant and tolerant of poor soil to the perennial herbs with strong resistance, and gradually changed to the neutral and sciophilous. Among them, Arundinella setosa could well adapt to the environment. The heliophilous tree species such as Rhamnus leptophylla,Myrsine africana,Carissa spinarum and Osteomeles anthyllidifolia were the pioneer species in this area. Their presence created conditions for other species, and they were gradually replaced by sciophilous species. These species could be used in the early stage of vegetation restoration. In the later stage of vegetation restoration, Quercus cocciferoides (Fagaceae) became a dominant species, which could be used in the shrub stage of vegetation restoration, or in the condition of artificial afforestation when conditions permitted. In the whole process of vegetation restoration, the predominance was shifting from short and small-stature species to tall and large-stature species, with increasing life span.

Key words: survival rate, body length., genetically modified soybean, reproductive rate,  Folsomia candida