Xue Hui-Ying, Luo Da-Qing, Yu Bao-Zheng
College of Resources and Environment, Tibet College of Agriculture and Animal Husbandry, Linzhi 860000, Tibet, China.
Ying Yong Sheng Tai Xue Bao. 2012 Dec;23(12):3402-8.
In order to understand the present status of nematode diversity in soil ecosystem of Abies georgei var. smithii forest, the typical forest type in subalpine zone of southeastern Tibet, an investigation was made on the nematode community in different soil layers of 0-30 cm depth from the summer, 2010 to the spring, 2011. The nematode individual density, diversity index, and trophic group index were taken to analyze the composition and structural characteristics of the soil nematode community. A total of 7915 soil nematodes belonging to 2 classes, 6 orders, 38 families, and 67 genera were collected by shallow dish method. The nematode individual density was averagely 620 nematodes x 100 g(-1) dry soil, and the nematode individuals in surface soil layer (0-5 cm) accounted for 56.9% of the total, indicating the obvious surface gathering characteristics of the nematode community. Tylencholaimus, Helicotylenchus, and Plectus were the dominant genus. Plant-parasite nematode was the dominant trophic group, while fungi-feeding nematode had the largest proportion among the non plant-parasite nematodes. Soil organic matter was mainly decomposed by fungi. The ANOVA analysis indicated that there were no significant differences in the Shannon, Pielou, Margalef, and Simpson indices of soil nematode community among different seasons. The Pielou index had no significant difference among different soil layers, while the differences of Shannon, Margalef, and Simpson indices tended to be increased with increasing soil depth. It was concluded that the A. georgei var. smithii forest ecosystem in Sejila Mountain had a high maturity, with strong resistance to environment disturbances.
为了解西藏东南部亚高山带典型森林类型急尖长苞冷杉林土壤生态系统中线虫多样性现状，于2010年夏季至2011年春季，对0-30厘米深度不同土层的线虫群落进行了调查。采用线虫个体密度、多样性指数和营养类群指数分析土壤线虫群落的组成和结构特征。通过浅盘法共采集到7915条土壤线虫，分属2纲、6目、38科、67属。线虫个体密度平均为620条线虫×100克-1干土，表层土壤（0-5厘米）中的线虫个体占总数的56.9%，表明线虫群落具有明显的表聚特征。盘旋线虫属、螺旋线虫属和小杆线虫属为优势属。植物寄生线虫是优势营养类群，而非植物寄生线虫中食真菌线虫所占比例最大。土壤有机质主要由真菌分解。方差分析表明，不同季节土壤线虫群落的香农指数、皮洛指数、玛格列夫指数和辛普森指数无显著差异。皮洛指数在不同土层间无显著差异，而香农指数、玛格列夫指数和辛普森指数的差异随土壤深度增加呈增大趋势。研究得出结论，色季拉山急尖长苞冷杉林生态系统成熟度高，对环境干扰具有较强的抗性。
