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Climate warming and human disturbance are known to be key drivers in causing range contraction of many species, but quantitative assessment on their distinctive and interactive effects on local disappearance is still rare. In this study, we examined the association of climate warming and human disturbance stressors with local disappearance probability of Brandt's voles (Lasiopodomys brandtii) in a steppe grassland in northern China. We used logistic generalized additive models to quantify the relationship between local disappearance probability of Brandt's voles and environmental variables. The year following the last observation year was used to estimate the disappearance threshold of Brandt's voles. We projected the distribution change of Brandt's voles under future climate warming scenarios. We found climate warming attributed to local disappearance and range contraction for southern populations of Brandt's voles from 1971 to 2020. Human stressors and high vegetation coverage increased the probability of local disappearance of voles in years of abundant precipitation. The southern boundary retreated northward at a speed of 99.0 km per decade with the temperature rise of 0.36°C. The disappearance threshold of maximum air temperature of Brandt's voles in the warmest month (27.50 ± 1.61°C) was similar to the lower critical temperature of its thermal neutral zone. Our study suggests that the rapid climate change over the past decades contributed to the range contraction of its southern boundary of this keystone species in the steppe grassland of China. It is necessary to take actions to preserve the isolated populations of Brandt's voles from the effects of accelerated climate change and human disturbance.

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To evaluate the antifertility effects of crude ethanol extracts of Tripterygium hypoglaucum (Levl.) Hutch in Mongolian gerbils. Crude ethanol extracts of T. hypoglaucum root (ETH R ) was administrated orally at a dose of 160 mg/kg for 30 days. Sperm density, sperm motility levels and the percentage of misshapen sperm in the cauda epididymides were assessed. The fertility rate of mated female gerbils was calculated. The results indicate that ETH R has an effect in Mongolian gerbils. Oral administration of ETH R caused an increase of the percentage of misshapen sperm significantly. Testis and epididymis weights, the sperm density and motility were significantly reduced. Compared to the control group, there was a distinct reduction in the number of litters produced, and the average number of pups per male decreased from 3.4 to 0.87. Reversibility tests showed that testis and epididymis weights, sperm indices, and fertility started to gradually recover after 30-days cessation of medication. The ETH R brought a significant decrease in birth rate of Mongolian gerbils.