Plant community stability and diversity play crucial roles in maintaining the stable performance of grassland ecosystem functions. In this study, we selected 55 representative grassland community sample plots in the Habahe Forest region of the Altai Mountains, Xinjiang. We examined the number of species, the number of individuals, and the cover of each species in the sample plots. Additionally, we determined the aboveground biomass of grassland communities, the stability of M. Godron communities, and plant diversity (using the Margalef index, Simpson index, Shannon–Wiener index, and Alatalo evenness index) in the sample plots. We analyzed community stability, plant diversity, and the correlation between community stability, plant diversity, and environmental factors (such as longitude, latitude, altitude, slope, humus thickness, soil thickness, air temperature, precipitation, and soil moisture). The results show that the plant coverage and height of different grassland types in the Habahe Forest area decrease from mountain meadow to desert steppe. The aboveground biomass and species diversity of meadows are significantly higher than those of steppes. The stability of different grassland types is as follows: montane steppe > montane meadow steppe > mountain meadow > desert steppe. The species richness of the four grassland types is positively correlated with community stability, while evenness is negatively correlated with community stability. Dominance in montane steppe and montane meadow steppe is significantly positively correlated with community stability, whereas diversity in desert steppe and montane steppe is significantly negatively correlated with community stability. Precipitation and soil moisture are the main factors affecting species diversity and stability in the Habahe Forest area. Soil nutrients and slope can also impact community stability by affecting species diversity. In summary, the ecological management of grasslands in the Habahe Forest area should consider climate, soil, and terrain factors, and different management measures should be selected to adapt to different grassland types.

This study quantitatively analyzes the effects of flooding on the growth and species diversity of riparian forests along the Yarkant River and the Tarim River, Xinjiang, in northwest China, and provides important information for the efficient utilization of water and water resource management in arid regions. Monitoring of species diversity of riparian forests was conducted every year from 2016 to 2019 in the Xiamale forest district in the lower reaches of the Yarkant River, and in the Shaya forest district and the lunnan forest district in the upper and middle reaches of the Tarim River. The Pielou index, Shannon–Wiener index, Simpson index, and importance value were used to analyze the influence of flooding. The results showed the following: (1) After three years of flooding, indices for the lower reaches of the Yarkant River and Tarim River were significantly increased and 11 new plant species appeared. (2) With increasing distance from the river channel, plant density and species diversity decreased. Flooding trends are the main factors affecting the distribution of plant species and water is the main restricting factor that influences plant growth in arid areas; thus, desert riparian forests improved significantly after flooding. (3) Flooding increases the regeneration capacity and species diversity of plant communities in desert riparian forests. In order to maintain the current trend of ecological improvement, flooding irrigation must continue.

As a key project of China’s western development, the West-East Natural Gas Transmission Project (WENGT) has effectively alleviated China’s uneven energy distribution and supply-demand issues. It has promoted the optimization of China’s energy structure and sustainable development in the new era, helping to achieve the goal of “double carbon”. Based on pollution data from Chinese industrial enterprises from 2000 to 2012, this paper analyzes the impact of the West-East Natural Gas Pipeline Project on the air pollution emissions of industrial enterprises using a difference-in-difference model and explores the moderating role of local government environmental regulations. The findings indicate that the project significantly reduced air pollutant emissions from industrial enterprises in cities along the route, with a more pronounced reduction effect in areas with higher environmental regulation intensity. Additionally, the emission reduction effect varied among different types of enterprises and regions, with private enterprises showing the smallest reduction impact and the eastern coastal region exhibiting the most significant effect. This paper delves into the relationship between sustainable cross-regional energy development and air pollution emissions from industrial enterprises, providing a theoretical basis for energy conservation and emission reduction policies in China.

Altitude, as a key environmental factor, shapes the spatial patterns of species diversity, phylogenetic diversity, and community phylogenetic structure. Studying grassland diversity and phylogenetic structure along altitudinal gradients helps clarify how altitude-driven environmental changes influence community assembly, and reveal vertical patterns in community formation. This study examines grasslands at 1300–2500 m elevation in the Two-River Source Forest Area, Altai Mountains, Xinjiang. Six elevation gradients (200 m intervals) were surveyed with 90 grassland quadrats, documenting community characteristics and environmental data. The study analyzes the patterns of species composition, diversity, and phylogeny across different elevation gradients and explores their relationships with key environmental factors. The results indicate that the grassland species composition is dominated by species from the Poaceae, Rosaceae, and Asteraceae families, with Poa annua (annual bluegrass) being the dominant species within Poaceae. The species diversity along the elevation gradient exhibits a bimodal trend, with an initial increase, followed by a decrease, another increase, and finally a decline as the elevation rises. In contrast, phylogenetic diversity shows a unimodal pattern, characterized by an initial increase followed by a decline with increasing elevation. Although the phylogenetic structure did not exhibit a significant trend of transitioning from divergence to clustering along the altitudinal gradient, the overall phylogenetic pattern of grassland communities tended toward clustering. Further analysis reveals significant correlations between species diversity and environmental factors such as temperature, precipitation, forest cover, and soil moisture. However, no environmental factors were found to have a significant correlation with the phylogenetic indices.

The stability, diversity, and biomass of grassland plant communities directly impact the functionality and resilience of ecosystems, making them a focal point for ecological research. This three-year study (2021–2023) in the Habahe pastoral area of Xinjiang, China, aimed to investigate the long-term effects of grazing on grassland vegetation structure, community stability, species diversity, and productivity. The results indicate the following. (1) The Habahe pastoral area hosts a relatively rich plant species diversity, with 40 species distributed across 17 families and 37 genera, predominantly comprising perennial and annual herbs. (2) Grazing significantly affected grassland structure and function, resulting in a 4.35% decrease in plant community stability, a 40.74% decrease in species richness, a 21.55% decrease in species dominance, a 5.08% decrease in species diversity, a 46.79% decrease in aboveground biomass, a 61.86% decrease in coverage, and a 72.12% decrease in height. (3) Grazing alters the relationship between species diversity and community stability, shifting it from a positive correlation to a negative one (p < 0.01) or rendering it non-significant after grazing. (4) Grazing affects the correlation between aboveground biomass and both species diversity and community stability. While the positive correlation between aboveground biomass and species diversity persists, it is not statistically significant (p > 0.05) after grazing. Conversely, the correlation between aboveground biomass and community stability shifts from positive to negative (p < 0.01). These results emphasize the need for integrated management strategies that consider both grazing intensity and plant community composition to maintain the health of grassland ecosystems.

Tree-ring width records provide crucial insights into historical vegetation dynamics and climate change. This study integrates tree-ring width index (RWI), MODIS NDVI remote sensing data, and 11 monthly extreme climate indices from Larix sibirica Ledeb. chronologies in the Burqin and Two-River Source regions of the Altai Mountains, Xinjiang, to investigate tree-ring-NDVI relationships and reconstruct vegetation coverage since the 19th century. Using LASSO regression to identify dominant extreme climate drivers and CMIP6 future climate scenarios, we projected radial growth trends and potential tree decline risks. Results demonstrate significant positive correlations between RWI and growing-season NDVI ( p < 0.05), reflecting tree-ring sensitivity to vegetation productivity changes. Pettitt tests revealed significant pre-mutation declining trends in historical vegetation coverage at both sites. Pearson correlation analysis revealed distinct response patterns of tree-ring width to extreme climate events between the two sampling sites. At the Burqin site, extreme precipitation during the previous autumn (October RX1day) significantly constrained radial growth. Conversely, elevated daytime temperatures (TX90p), greater diurnal temperature ranges (DTR) prior to the growing season, and short-duration heavy precipitation events (RX5day) during transitional periods and critical growth months exerted positive effects on tree growth. The Two-River Source site exhibited contrasting responses: anomalously warm autumn conditions (TN90p) following the previous growing season led to subsequent growth suppression. Extreme temperature events during the current year demonstrated dual effects - while temperature extremes (TXx) and warm events (TX90p/TN90p) inhibited radial growth, cold extremes (TX10p/TN10p) and increased diurnal temperature ranges (DTR) exhibited moderate growth-enhancing effects. CMIP6-based projections indicate significant future growth declines across the Altai Mountains. This study advances understanding of extreme climate impacts on forest ecosystems through a novel multi-proxy approach combining dendrochronology and remote sensing. Our findings provide scientific foundations for conservation, restoration, and adaptive management of forest ecosystems under climate change.