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Environmental stressors and disturbances can cause changes in an ecosystem's community structure, which can be reflected in its functional diversity. As grazing intensity increases, this causes changes in the environment that inevitably lead to changes in the community structure, which can especially affect rodents due to their sensitivity to the environment. The effects of grazing prohibition and overgrazing on the functional diversity of desert rodent communities in Alxa were studied in April, July, and October of 2018–2020. The trap‐day method was used to study rodent communities in disturbed habitats. Five functional traits were selected and quantified: nutrition, life history, physiology, morphology, and activity rhythm. The results showed that: (1) The species composition of rodent communities in the Alxa Desert in spring and autumn was significantly correlated with the functional traits of the hibernation, reproductive cycle, and feeding habits. The species composition in the summer was only significantly correlated with the functional traits of reproductive cycle and diet. (2) The effects of overgrazing on the functional diversity of rodents in desert areas have significant temporal and spatial characteristics. (3) In spring and summer, overgrazing made the Functional Richness index of the rodent community lower than that of areas where grazing is prohibited, but the Functional Evenness index was higher than that of grazing‐prohibition areas. In autumn, overgrazing increased the Functional Richness index of the rodent community and decreased the Functional Evenness index. The Functional Divergence index was higher in overgrazing areas than in grazing‐prohibited ones. These results suggest that, in spring and summer, overgrazing reduced the ecological space utilization ability of rodent communities; however, the impact on the degree of utilization of community resources is more comprehensive. In autumn, overgrazing increases the ability of rodent communities to use ecological space but reduces resource efficiency. Overgrazing makes the niche differentiation of rodent communities higher, the degree of overlap lower, and the competition between species weaker. Therefore, overgrazing will affect the functional diversity of the community through the utilization of ecological space, resource utilization, interspecific competition, and niche. [ABSTRACT FROM AUTHOR]

Rodent pest population outbreaks occur frequently in grassland ecosystems in northern China. The Mongolian gerbil ( Meriones unguiculatus) is a dominant pest rodent which is distributed across the semi-desert grasslands of Inner Mongolia, China. In 2009, we studied the contraceptive effect of levonorgestrel-quinestrol (EP-1), concentration 50 ppm, on a wild Mongolian gerbil population. The one-off contraceptive treatment was compared with a control group using a semi-monthly live trapping method in the Ordos Semi-desert Grassland Region of Inner Mongolia. The results show that juveniles were not recruited in spring in the treatment group. Ratios of juveniles in the control and treatment groups showed significant semi-monthly differences from spring to summer (one-way ANOVA, F2, 14= 7.53, P < 0.05). Between both groups, annual fluctuations of juvenile and total population densities were significantly different respectively ( F2, 14= 4.64, P < 0.05; F2, 18= 7.72, P < 0.05). The contraceptive EP-1 delayed the normal reproductive pattern of Mongolian gerbil populations. This suppressed birth rates of gerbil populations, reduced their densities, and changed their age structures. The period of EP-1 baiting should be extended but it could be an ideal method for controlling Mongolian gerbil populations during each breeding season. [ABSTRACT FROM AUTHOR]

False zokor (Myospalax aspalax) is one of the subterranean rodents distributed in East Asia. Molecular data and demography ofM. aspalaxare unknown, and the population management is difficult, because it is specialized for underground life. In this study, the complete mitochondrial DNA genome ofM. aspalaxwas determined. The results suggested that the mitogenome was 16,436 bp in length, and consisted of 13 protein-coding genes, 22 transfer RNA genes, two ribosomal RNA genes, and one displacement loop. The overall base composition of the heavy strand was A 33.40%, T 29.34%, C 24.90%, and G 12.36%, with A + T > C + G.Myospalax aspalaxis a sister to the genusMyospalax,and have a most closely relationship withM. psilurus. The mitogenome data are potentially important for population management ofM. aspalaxand should contribute to the interspecies comparative analyses of genusMyospalax. [ABSTRACT FROM AUTHOR]