模拟增温、施氮对荒漠草原土壤中小型动物群落的影响

Effect of simulated warming and N addition on soil mesofauna community in desert steppe of Inner Mongolia

为了解全球气候变化对内蒙古荒漠草原土壤动物的影响,以四子王旗短花针茅荒漠草原为研究对象,采用野外增温、施氮、增温施氮和对照处理,观测土壤中小型动物群落的变化。结果表明,荒漠草原土壤动物不同类群对增温、施氮的响应不同:1)增温显著降低短花针茅荒漠草原鞘翅目幼虫类群数,对其它土壤动物无显著影响;施氮显著提高弹尾目昆虫的密度以及中气门亚目昆虫的密度和类群数,对其它土壤动物无显著影响;增温施氮显著降低鞘翅目幼虫密度和类群数,对其它土壤动物无显著影响。2)短花针茅荒漠草原土壤中小型动物有明显表聚性,其中增温施氮0-10cm密度显著高于10-20cm;施氮0-10cm密度和类群数均显著高于10-20cm。研究表明,气候变暖和氮沉降有可能影响土壤动物的群落组成和垂直结构。

To understand the effect of global climate change on soil fauna in Inner Mongolian desert steppe,we studied the effect of warming,N addition,their interaction of the warming and the N addition and control on soil mesofauna community in the Stipa breviflora desert steppe of Siziwang Banner. The results showed that soil fauna in various groups in desert steppe responsed to warming and N addition differently： 1） Warming significantly reduced the taxnon of Coleoptera larvae in Stipa breviflora desert steppe,however,had no significant effect on the other soil fauna; N addition significantly increased the density of Collembola and the density and group number of Mesosigmata,however,has no significant effect on the other soil fauna; The interaction of the warming and the N addition significantly reduced density and group number of Coleoptera larvae,however,has no significant effect on the other soil fauna. 2） Vertical distribution of soil fauna in Stipa breviflora desert steppe had obvious surface assembly： in the interaction of the warming and the N addition,the density in 0- 10 cm was significantly higher than 10- 20 cm. In N addition treatment,the density and group number in 0- 10 cm was significantly higher than10- 20 cm. Our study found that climate warming and nitrogen deposition may affect soil fauna community composition and vertical structure.