| The rodent communitiy and population dynamics in Alashan desert of Inner Mongolia was investigated by mark-and-recapture method between 2002 and 2010. The study was performed in four different kinds of disturbed habitat: prohibited-grazing area, rotational-grazing area, over-grazing area and farmland area.The purposes of research were to reveal the dynamic characteristics of rodent community and each species populations, and their interference in response to the different disturbance. First of all, we analyze the population dynamic features of each species in the same kind of disturbed habitat, and the features of same species in four different kinds of disturbed habitat. Secondly, the species number, biomass, and diversity index of rodent community were analysed in different kinds of disturbed habitat, and then the month and annual dynamic of capture proportion of each species were analysed to understand the characteristics of rodent community succession. Finaly, to explore the decisive role of population density and community variables to the communities structure and dynamic, the correlation between population density of species and seven ecology variables of community were synthetically analysed. The results are as follows:(1) Between 2002 and 2010, 3400 individuals belong to 3 families and 9 species were captured and marked in four different kinds of disturbed habitat. The species number in over-grazing area was the most, and the farmland area was less, they were respective 9 and 6. The size order of species number was over-grazing area > rotational-grazing area > prohibited-grazing area > farmland area in four different kinds of disturbed habitat.(2) The population density of each species had significant season and annual fluctuation, especially the population density of dominant species in the highest was significantly higher than the lowest year. The annual dynamics of each species in the same disturbed habitat had a weak correlation, which suggested that the asynchrony of population dynamics can reduced the role interspecific competition, and can promoted the stability of the community.(3) The strong spatial synchrony of dominant species was detected, and the spatial synchrony of common species was weak. It was probably a significant ecological suitability that dominant species have the strong spatial synchrony while common species have weak spatial synchrony, and it was very important to balance and stability of animal community.(4) Desert rodent in four different kinds of disturbed habitat basically corresponds to two important metapopulation criteria, they were dispersal occurs between local populations and the dynamics of local populations are in asynchrony respectively. Desert rodent in four different kinds of disturbed habitat was an ideal system for the combination of metapopulation theory and experimental study.(5) The seasonal fluctuation of rodent community biomass was obvious differences, and appeared the shape of single peak type in four different kinds of disturbed habitat. The fluctuation range of prohibited-grazing area was largest, and rotational-grazing area took the second place, while the over-grazing area and farmland area had small fluctuation. The community biomass of farmland area was significantly lower than othe disturbed habitat, and there was no significant difference among other three disturbed habitat.(6) The succession of community structures occurred in four kinds of disturbed habitat between 2002 and 2010, and the succession process had a significant difference among the disturbed habitats. The dominant species played an important decisive role to community succession than the common species and rare species of community.(7) It was a significant positive correlation population density and community biomass (P<0.05), and their changing trend was similar. The population density of dominant species had a strong correlation with community biomass and total population density. Dominant species played an irreplaceable role to desert community. The population density and biomass of dominant species can determine the population dynamic, community biomass, community dynamic and succession.
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