热振森林大型土壤动物群落特征及其影响因素

为了解西藏拉萨市林周县热振国家森林公园不同海拔大型土壤动物群落的空间分布特征及其与环境因子的关系,于2021年7月(夏季)根据其地理特征设置了三个不同海拔共9个样地.采用手捡法对大型土壤动物进行收集,并将其保存在75%酒精的收集管中,同时测定相应的环境因子.共捕获大型土壤动物1427个,经形态学鉴定隶属于2门5纲15目21科,其中优势类群为姬马陆科(Julidae)和蚁科(Formicidae),占总捕获量的66.0%.常见类群共10类,占总捕获量的31.3%;稀有类群占总捕获量的2.7%.热振国家森林公园大型土壤动物的类群、Shannon多样性指数、均匀度指数和优势度指数在三个不同海拔之间无显著性差异(P>0.05).大型土壤动物群落Jaccard相似性系数位于0.15~0.77.Pearson相关性结果显示,大型土壤动物个体数与海拔呈极显著负相关(P<0.01),与土壤温度和pH呈显著正相关(P<0.05);冗余分析显示,排序轴1和轴2共同解释了的类群组成变化的55.0%,全磷(TP)和有效磷(AP)为显著性解释变量,对大型土壤动物群落的解释率分别为29.6%和18.5%,是影响大型土壤动物群落的主要环境因子.

Community characteristics of soil macrofauna and its influencing factors at Rating Forest

The spatial distribution characteristics of soil macrofauna communities and their relationship with environmental factors were analysed with 9 plots. The soil samples were set up at three elevation zones according to the geographical features in July 2021. The soil macrofauna were collected by hand and stored in 75% alcohol, and the influencing environmental variables were recorded at the same time. A total of 1427 soil macrofauna were captured belonging to 21 families, 15orders, 5 classes and 2 phyla. Among them, the dominant groups were Julidae and Formicidae, accounting for 66.0% of the total soil macrofauna. There were 10 common taxa accounting for 31.3% of the total number of soil macrofauna, and 2.7% of rare taxa. There were no significant differences in the number of group, Shannon diversity index, evenness index and dominance index of the soil macrofauna between three different elevation zones (P>0.05). The Jaccard similarity coefficient ranged from 0.15 to 0.77 of soil macrofauna communities. The number of soil macrofauna was negatively correlated with altitude (P<0.01) and positively correlated with soil temperature and pH (P<0.05) significantly. Redundancy analysis (RDA) showed that RDA axis 1and axis 2 explained 55.0% of the accumulative variation in soil macrofauna group composition. Total phosphorus and available phosphorus were significant explanatory variables, accounting for 29.6% and 18.5% of the variation in soil macrofauna communities, respectively.