岩溶山区石漠化生态治理的植物多样性动态响应——以贵州省花江示范区顶坛小流域为例

Response of Plant Diversity to the Rehabilitation for Rocky Desertification in Karst Mountainous Areas:A Case Study of the Dingtan Catchment of Huajiang Demonstration Area in Guizhou

以贵州省花江示范区顶坛小流域2005、2007、2010年治理区为研究对象,根据石漠化等级及植被演替特征,选择强、中、轻和潜4个等级的石漠化样地进行调查,研究其植物多样性变化。结果表明:1)在人为干扰作用下,植物数量特征的空间变异程度较高,但植物的高度、地径、冠幅、生物量均呈较明显增长趋势;2)植物种群特征中优势种较为突出,除强度石漠化区外,花椒(Zanthoxylum bungeanum)群落2005、2007、2010年在中度石漠化群落中占16.5%、16.5%、16.8%,在轻度石漠化群落中占26%、25.9%、29.2%,在潜在石漠化群落中占37.9%、39.2%、51.3%,呈现逐年增长趋势;3)在群落分类上以禾本科(Gramineae)、菊科(Compositae)、大戟科(Euphorbiaceae)、桑科(Moraceae)和凤尾蕨科(Pteridaceae)为主;4)植物物种多样性特征上,表现出随石漠化等级的降低而降低的趋势。上述结论表明,不同等级石漠化区植被生长、群落分布及多样性特征均不尽相同,应采取相应的恢复措施。

Ecological vegetation restoration is a core part of the rehabilitation project for rocky desertification. Dingtan Catchment of Huajiang Demonstration Area in Guizhou Province, which was rehabilitated in 2005, 2007 and 2010, was taken as the study area, 4 sample plots were selected at intense, moderate, slight and potential grades respectively according to the grades of rocky desertification and the characteristics of vegetation succession to research the changes of the plant diversity. The results show that under the disturbance of human activities, the number of plants varies spatially, but the height, ground diameter, crown width and biomass of plants present an obvious increase tendency.The flora feature is that dominant species： Zanthoxylum perform noticeably which accounts for 16.5%, 16.5% and 16.8% of the flora in moderate rocky desertification areas respectively in 2005, 2007 and 2010; 26%, 25.9% and 29.2% in slight rocky desertification areas; and 37.9%, 39.2% and 51.3% in potential rocky desertification areas, and there is an increasing tendency in the proportion. According to the flora classification, plants mainly belong to Gramineae, Compositea, Uphorbiaceae, Moraceae, and Pteridaceae. There is a decreasing tendency of plant diversity with degradation of rocky desertification. The above results indicate that relevant measures should be implemented in different areas with different grades of rocky desertification because of the difference of their vegetation growth, flora distribution and diversity..