【摘要】 为了解土壤纤毛虫群落对退耕还林生态恢复的响应且将其作为评价生态恢复效果的重要参数,采用"非淹没培养皿法"、活体观察法和培养直接计数法对甘肃省陇南市徽县退耕还林区3个不同退还林型样点和1个撂荒地(对照)样点的土壤纤毛虫群落特征、植被群落特征和土壤理化指标进行了研究。结果显示:共鉴定土壤纤毛虫127种,隶属于9纲18目28科47属,恢复样点的土壤纤毛虫物种数、密度和物种多样性指数均显著高于对照样点;优势类群由对照样点的肾形目(Colpodida)演替为恢复样点的散毛目(Sporadotrichida),即随着退耕还林工程的进行,纤毛虫群落趋于复杂化。相关性分析显示,土壤纤毛虫群落与地上植被关系密切,且含水量、有机质、全氮和电导率为影响土壤纤毛虫群落组成的主导因子。该结果表明,退耕还林后,植被逐渐恢复,土壤理化因子发生变化,土壤纤毛虫群落对生态环境的恢复做出了积极的响应,因此土壤纤毛虫群落特征参数可以作为评价退耕还林效果的重要指标。更多还原

【Abstract】 The responses of soil ciliate communities to the returning of cropland to forest were investigated to examine whether ciliates can be used to evaluate the effects of ecological restoration.Four sampling sites were selected,with three different returned forest types and an abandoned land as control in Hui County of Longnan City,Gansu Province,China. At each site,the community characteristics of soil ciliates and vegetation,along with physical and chemical parameters of the soil,were analyzed. Ciliates were isolated from the soil using non-flooded Petri dish method and in vivo observation. Enumeration was carried out using direct-culture counting method. A total of 127 soil ciliate species belonging to 9 classes,18 orders,28 families,and 47 genera were identified. The species richness,density,and species diversity index of soil ciliates in the ecologically restored sites were significantly higher than those of the control site. The dominant group changed from Colpodida in control site to Sporadotrichida in ecologically restored sites,indicating that soil ciliate communities tended to complicate with the progress of the returning cropland to forest project. Soil ciliate community characteristics were closely related to vegetation type. Soil water content,organic matter content,total nitrogen content,and electrical conductivity were the dominant factors affecting soil ciliate community composition. After returning cropland to forest,the vegetation gradually recovered,soil physical-chemical factors changed,and soil ciliate communities showed positive response to the restoration of ecological environment. These findings suggest that ciliate community composition can be used as an indicator for the successful restoration of cropland to forest.更多还原