广州市不同土地利用方式下冬季土壤动物群落结构的研究

对广州市越秀区和天河区3种土地利用方式(绿地、林地、农田)下、6种不同样地(人民公园东部绿地、天河体育中心广场绿地、华南植物园、华南农业大学树木园、郊区岑村农田和郊区凤凰街农田)中小型土壤动物群落的数量和结构组成、分布及其变化规律进行了研究。调查期间共获得中小型土壤动物1 365个,共25个类群,分别隶属于7门16个类群,优势类群为线虫纲(Nematoda)、蜱螨目(Acarina)和弹尾目(Collembola),共占总捕获量的83.44%。不同样地生境中土壤动物的类群组成以及个体数不同。各样地土壤动物群落复杂性指数(C)以华南植物园为最高,达2.822,人民公园绿地为最低。观测样地中小型土壤动物表现出明显的表聚现象,垂直分布有明显差异,类群数和个体数随深度增加而减少。群落排序的结果显示,土壤动物群落对人类活动干扰的响应有所不同,其中倍足纲(Diplopoda)和石目(Archaeognatha)这两类土壤动物为稀有类群,仅在观测的林地类样地中有分布,对干扰最为敏感,可用于指示城市化进程S中土地利用类型的变化。

Soil faunal community structure in winter season under variousland use types in Guangzhou

Rapid urbanization process changes the spatial pattern of land utilization, soil physical and chemical properties. As an important part of urban ecosystem, soil animals have been used in monitoring researches of many environmental problems from urbanization, in which some of them may be used as indicator species to monitor and evaluate soil quality and health as well as one of the main influential factors on material cycles. To better know the impacts of urbanization on soil animals community and soil ecosystem, we took Tianhe and Yuexiu Districts of Guangzhou City as a case study area, 6 sites from three different land use systems including the two woodlands, two grasslands and two farmlands were selected as the investigation sites in January 2008. Soil meso- and micro- faunal communities in six sites located in three different land use types were investigated. The total number and groups of soil meso- and micro- fauna genera sampled were 1 365 and 25 respectively, belonging to 7 phyla. Dominant genera were Nematoda, Acarina and Turbellaria, comprising 83.44% of total samples collected. The community complexity index (C), a measure of the complexity and diversity of the communities was highest (2.822) in forestland of the South China Botanical Garden plot and lowest in grassland of the Ren Min Park plot. The vertical distribution of soil meso- and micro-faunal communities in the six sampling plots showed clear surface assembly, with the total number of soil fauna and genera declining with soil depth. Detrended correspondence analysis indicated that soil animal communities responded differently to varying intensities of human activities. Rare genera within the Orders of Diplopoda and Archaeognatha could be only found in the two forestland plots and very sensitive to human disturbance, indicating that soil fauna within these two orders might be used to detect land use changes resulting from urbanization. The results of this study provided scientific and fundamental data for the indicative function of the soil quality change by giving a survey of variations of soil meso- and micro-faunal community's composition and distribution under the influences of rapid urbanization. Moreover, the study pointed out that future studies should integrate the studies of the soil animals and changes in land use type for the enhancement or improvement of soil quality.