陕北黄土高原典型草地土壤动物群落的基本特征--以吴起金佛坪小流域为例

Basic characteristics of soil fauna in typical grasslands on the Loess Plateau in northern Shaanxi

为研究陕北高原典型草地土壤动物群落的基本特征,于2021年春季和夏季就吴起金佛坪小流域的阴坡、阳坡和沟底共7个草地样点的的土壤样品进行采集,同时利用Tullgren干漏斗法和Baermann湿漏斗法进行干湿生土壤动物筛选,并通过室内鉴定,分析其群落组成和特征。结果表明:1)春夏两季共捕获土壤动物1232头,隶属于3门7纲14目。其中优势类群为真螨目(30.19%)、甲螨亚目(20.7%)、蚁科(14.69%)和弹尾目幼虫(10.39%),稀有类群有24个类群,共占总个体数的6.82%。2)土壤动物群落组成、密度存在明显的季节差异,春季各坡向土壤动物类群数和个体密度差异不显著,夏季沟底和阴坡极显著高于阳坡(P<0.01)。春夏两季多样性指数变化趋势不一致,春季不同坡向各指数均无显著性差异,夏季阳坡与阴坡和沟底的Shannon-Wiener指数以及Simpson指数均存在显著性差异(P<0.05)。3)PCA排序显示不同季节群落相似性特征不同。总体而言,陕北黄土高原草地土壤动物群落组成随季节和坡位变化的特征说明他们与环境的关系是非常密切的。

In order to study the basic characteristics of typical grassland soil fauna on the northern Shaanxi Plateau,soil fauna was collected from 7 grassland sample sites in the shady slope,sunny slope and ditch bottom in the Jinfoping small watershed in Wuqi county in spring and summer of 2021.At the same time,Tullgren method and Baermann method were used to screen dry and wet soil animals,and their community composition and characteristics were analyzed through indoor identification.The results showed that:1)A total of 1232 soil animals were captured in spring and summer,belonging to 14 orders,7 classes and 3 phyla.Among them,the dominant groups are Acariformes(30.19%),Oribatida(20.7%),Formicidae(14.69%)and Collembola larvae(10.39%).There are 24 rare taxa,accounting for 6.82%of the total number of individuals.2)There were obvious seasonal differences in soil animal community composition and individual density.In spring,the number of soil animal groups and individual density of each slope direction were not significantly different.The variation trend of diversity index in spring and summer was inconsistent,and there was no significant difference in each index among different slope aspects in spring.In summer,there were significant differences in Shannon-Wiener index and Simpson index between sunny slopes and shady slopes,and ditch bottoms(P<0.05).3)PCA ranking showed that the community similarity characteristics were different in different seasons.Overall,the characteristics of changes in the composition of grassland soil fauna on the Loess Plateau in northern Shaanxi with seasons and slope positions indicate that they are closely related to the environment.