The red imported fire ant, Solenopsis invicta (Hymenoptera: Formicidae), is an invasive pest, and it has spread rapidly all over the world. Predicting the suitable area of S. invicta growth in China will provide a reference that will allow for its invasion to be curbed. In this study, based on the 354 geographical distribution records of S. invicta, combined with 24 environmental factors, the suitable areas of S. invicta growth in China under current (2000s) and future (2030s and 2050s) climate scenarios (SSPs1-2.5s, SSPs2-3.5s and SSPs5-8.5s) were predicted by using the optimized MaxEnt model and geo-detector model. An iterative algorithm and knife-cut test were used to evaluate the important environmental factors that restrict the suitable area under the current climatic conditions. This study also used the response curve to determine the appropriate value of environmental factors to further predict the change and the center of gravity transfer of the suitable area under climate change. The optimized MaxEnt model has high prediction accuracy, and the working curve area (AUC) of the subjects is 0.974. Under climatic conditions, the suitable area is 81.37 × 10⁴ km² in size and is mainly located in the south and southeast of China. The main environmental factors affecting the suitable area are temperature (Bio1, Bio6, and Bio9), precipitation (Bio12 and Bio14) and NDVI. In future climate change scenarios, the total suitable area will spread to higher latitudes. This distribution will provide an important theoretical basis for relevant departments to rapidly prevent and control the invasion of S. invicta.

The Alligator Gar (Atractosteus spatula) is a very dangerous species that has an extremely destructive impact on the ecological environment in aquatic areas. As a kind of ornamental fish, it is spreading rapidly all over the world. In order to avoid or delay the spread of Alligator Gar in China, it is urgent to further monitor and clarify its distribution range within the country. In this study, a maximum entropy model (MaxEnt) and geographical information system (ArcGIS) were used to identify suitable regions under climate change scenarios in China, and the significance of environmental factors that shape this species’ distribution were evaluated. According to the geographical distribution data of Alligator Gar and selected environmental variables, the potential habitat area of Chinese Alligator Gar under four climate scenarios in the present (2000s) and future (2050s and 2070s) was predicted. (1) The main environmental variables affecting the potential geographical distribution of Alligator Gar are temperature factor variables (the mean temperature of the warmest quarter and the mean temperature of the coldest quarter), precipitation factor variables (precipitation in the driest month and in the driest quarter), and altitude. (2) Under the current climate conditions, the suitable breeding areas of Alligator Gar are mainly concentrated in the Guangxi Zhuang Autonomous Region, Guangdong Province, and Hainan Province. Under the four future climate scenarios, the distribution area of the total suitable area of Alligator Gar will gradually decrease, and the suitable area of Alligator Gar will spread to high latitudes.

The North and South Mountains of Lanzhou City are the ecological protection barriers and an important part of the ecological system of Lanzhou City. This study takes the North and South Mountains as the study area, calculates the soil erosion modulus of the North and South Mountains of Lanzhou City based on the five major soil erosion factors in the RUSLE model, and analyses the spatial and temporal dynamics of soil erosion in the North and South Mountains of Lanzhou City and the soil erosion characteristics under different environmental factors. The results of the study show that: The intensity of soil erosion is dominated by slight erosion, which was distributed in the northwestern and southeastern parts of the North and South Mountains in 1995, 2000, 2005, 2010, 2015 and 2018. Under different environmental factors, the soil erosion modulus increased with elevation and then decreased; the soil erosion modulus increased with a slope; the average soil erosion modulus of grassland was the largest, followed by forest land, cultivated land, unused land, construction land, and it was the smallest for water; except for bare land, the average soil erosion modulus decreases with the increase of vegetation cover; Soil erosion modulus was the greatest in the pedocal of the North and South Mountains, and the least in the alpine soil.

Biodiversity loss has become a global ecological crisis, and the conservation of Critically Endangered (CR) species is particularly urgent. In response, this study focuses on two CR bird species with markedly contrasting ecological traits, Emberiza aureola and Aythya baeri. Using species occurrence records and 22 environmental variables, we applied the MaxEnt model to simulate their potential suitable habitats. The results indicate that: the distribution of Emberiza aureola is primarily driven by precipitation of the driest month, precipitation seasonality, and slope. Its habitat suitability shows a unimodal response to isothermality and is enhanced in flat plains characterised by higher precipitation in the driest month and moderate precipitation seasonality. In contrast, Aythya baeri is strongly influenced by slope, precipitation of the warmest quarter, and mean temperature of the driest quarter, exhibiting a bimodal response to isothermality. Its suitability peaks under low precipitation conditions in the warmest quarter, reflecting its reliance on shallow, low-disturbance wetlands in open plains. The spatial distribution patterns of the two species differ markedly. Although both are confined to low-relief areas with slopes below 1°, the suitable habitats of Emberiza aureola are more extensive and continuous, with high-suitability areas concentrated in the Northeast China Plain and eastern Inner Mongolia. In contrast, the suitable habitats of Aythya baeri are highly fragmented and concentrated in the coastal wetlands of Liaodong Bay and the lake systems of the middle and lower Yangtze River Basin. By systematically comparing the distributional patterns of these two CR species at a macroecological scale, this study clarifies the constraints imposed by climatic and topographic factors, providing scientific support for optimising China’s protected area networks, implementing targeted wetland restoration, and advancing differentiated habitat management.