| The metacommunity concept has provided a new and revolutionary paradigm for community ecology by emphasizing integrated variation among communities at the regional level that is accentuated by biotic interactions and spatial variation in environmental characteristics and modulated by dispersal among sites.The basest problem of metacommunity research is the multiple species coexistence mechanism, and the formation of diversity reason and maintaining mechanism in the same system. So we must test the explaination of metacommunity structure of four ecological paradigm:the species sorting (SS), the mass-effect (ME), the neutral model (NM) and patch dynamics (PD) type.A variety of studies have been performed to verify the four ecological paradigm, but only less concerning about the terrestrial vertebrates system. The research is based on Alashan desert rodents fauna investigation, and from2006to2012, in the8fixed sample of Inner Mongolia Alashan zuoqi southern desert landscape, we examined the relative contributions of regional spatial characteristics and local environmental conditions to determine desert rodent species composition, and further analyze the community dynamics in different time scale and different season.The results showed that:(1) In the rodent faunal survey, Jaccard and Sorenson diversity index of rodent were the same variation trend, Cody diversity index fluctuation and variation was on the contrary with the Jaccard and Sorenson diversity index, and vegetation is important factor to affect rodent coexisting.(2) The investigation of the faunal rodents show that the environmental component to rodent species composition was greater than the spatial component and both pure spatial and pure environmental characteristics accounted for significant amounts of variation in rodent species composition. Results from variance decomposition suggest that the mass effects model describes the rodent metacommunity structure.(3) The investigation of fixed sample plot rodent show that the environmental component to rodent species composition was greater than the spatial component and pure environmental characteristics accounted for significant amounts of variation in rodent species composition. Results from variance decomposition suggest that the species sorting model describes the rodent metacommunity structure. (4) In different time scale, rodents dominant species in the region did not change, the rodent dispersal was proliferation of rat species and actual quantity increasing.(5) In different time scale, herb coverage were significantly affect rodent species composition, spatial axis and the relationship between rodent species are weaker than environmental axis and the relationship of rodent species. The species sorting model describes both metacommunity structure of rodent.(6) In different seasons (spring, summer, autumn), as the change of seasons rodent species change composition. In different seasons, the environmental component to rodent species composition was greater than the spatial component and pure environmental characteristics accounted for significant amounts of variation in rodent species composition. In different seasons, the species sorting model describes both metacommunity structure of rodent. |
