Redundancy analysis between rodent communities and plant factors in desert

The rodent community were sampled by a trap-day method in four different disturbance habitats in April, July and October (spring, summer, autumn) from 2009 to 2011 in Alashan desert. The habitats were farmland, rotational-grazing, over-grazing and prohibited-grazing areas, and the relationships between rodent community and plant factors were analyzed by Redundancy Analysis (RDA). The results showed that rodent community diversity indices (H) between different disturbance habitats were significant difference (P＜0.05) in three seasons. The highest diversity index of rodent community was found in rotational-grazing area (1.42) and the lowest was the over-grazing area (0.91) in spring; in the same way, the highest index was found in farmland area (1.45) and the lowest was the grazing-exclusion area (1.06) in summer; the highest index was found in over-grazing area (1.23) and the lowest was the grazing-exclusion area (0.65) in autumn. The RDA with forward selection showed that variations of rodent community were significantly related to coverage of suffruticosa plant and density of herbaceous plant in spring and summer, density and coverage of herbaceous plant in autumn. We suggest that coverage and density of plants are the most important factors influencing the structures of rodent community in Alashan desert.