茂兰喀斯特植被恢复过程群落数量特征及健康度研究

为揭示茂兰喀斯特植被恢复过程群落数量特征及健康度特点,以茂兰国家级自然保护区退化喀斯特植被自然恢复演替过程6个阶段群落为研究对象,选择10个数量指标,从群落组织力、能量和稳定性三方面对各恢复阶段群落数量特征及健康度进行综合分析,结果表明:(1)草本层中I阶段草本高度和密度最大;灌木数量在V阶段最多,在900 m~2内达5174株;(2)群落各层次生物量差异显著,演替过程中,木本植物及总体群落的生物量均呈增长趋势,全光照利用率以各阶段建群层最佳;(3)乔木层多样性指数H'、生态优势度λ、稳定性系数变化均呈递减趋势,且都在IV-V阶段下降最快,而后平缓;草本层、灌木层则变化各异;(4)随着植被正向演替,群落乔木层健康度指数为上升型,灌木层为单峰型,草本层为下降型;(5)草本层贡献率为下降型,灌木层为单峰型,乔木层为上升型。

Study on the Quantitative Characteristics and Health Index of the Natural Restoration Process of Karst Vegetation in Maolan Nature Reserve,Libo County,Guizhou Province

In order to reveal the quantitative characteristics and health index of vegetation restoration process in Maolan Karst areas, six stages of the natural restoration process of degraded Karst forest in Maolan National Nature Reserve were selected as research object.Based on 10 quantitative indexes, the organization, energy and stability of the community in each stage were analyzed for the quantitative characteristics and health index.The results showed that: 1) The height and density of herbs were the largest in stage I, and the number of shrubs was maximized in stage V, reaching 5174 stems in an area of 900m2.2) The level of community biomass was significantly different in the process of succession;the biomass of woody plants and the whole community showed an increasing trend, and the utilization ratio of solar radiation was the highest at the building layer of each stage.3) Tree layer diversity index, ecological dominance index and stability coefficient showed a decreasing trend, and declined fast at stages IV-V and then slowly stabilized;while those of herb layer and shrub layer varied.4) With the positive succession of vegetation, the health index of tree layer was up, that of shrub layer was a single peak type, and that of herb layer was a declining type.5) The contribution rate of the herb layer decreased, that of shrub layer was single peak type, and that of tree layer increased.