Oasis landscape change and its pattern dynamics are considered one of the vital research areas on global land use and landscape change in arid regions. An agricultural oasis is the main site of food security and ecosystem services in arid areas. Recently, the dramatic exploitation of agricultural oases has affected oasis stability, inducing some ecological and environmental issues such as water shortage and land degradation. In this study, the Qira oasis on the southern margin of Tarim Basin, Northwest China, was selected as a study area to examine the spatiotemporal changes in an agricultural oasis and the influence on oasis landscape pattern. Based on the integration of Thematic Mapper, Enhanced Thematic Mapper Plus, and GF-1 images, the agricultural Qira oasis has rapidly increased, with annual change rates of −0.3%, 1.6%, 3.7%, and 1.5% during 1970–1990, 1990–2000, 2000–2013, and 2013–2016, respectively. With the agricultural oasis expansion, the agricultural land has increased from 91.10 km² in 1970 to 105.04 km² in 2016. The percentage of farmland area has increased by 15.3% in 2016 compared with that in 1970. The natural vegetation is decreasing owing to the reclamation of desert–oasis ecotone. The oasis landscape change and pattern are mainly affected by agricultural expansion under water-saving technological utilization, land use policy, and regional economic development demand. The expansion of agricultural oasis is alarming due to human overexploitation. Thus, the government should adjust the layout of agricultural development and pay considerable attention to the oasis environment sustainability. This study can provide a valuable reference on the impact of climate change and human activities on a landscape.

Soil moisture is a vital factor affecting the hydrological cycle and the evolution of soil and geomorphology, determining the formation and development of the vegetation ecosystem. The previous studies mainly focused on the effects of different land use patterns and vegetation types on soil hydrological changes worldwide. However, the spatial heterogeneity and driving factors of soil gravimetric water content in alpine regions are seldom studied. On the basis of soil sample collection, combined with geostatistical analysis and the geographical detector method, this study examines the spatial heterogeneity and driving factors of soil gravimetric water content in the typical alpine valley desert of the Qinghai–Tibet Plateau. Results show that the average value of soil gravimetric water content at different depths ranges from 3.68% to 7.84%. The optimal theoretical models of soil gravimetric water content in 0–50 cm layers of the dune are different. The nugget coefficient shows that the soil gravimetric water content in the dune has a strong spatial correlation at different depths, and the range of the optimal theoretical model of semi-variance function is 31.23–63.38 m, which is much larger than the 15 m spacing used for sampling. The ranking of the influence of each evaluation factor on the alpine dune is elevation > slope > location > vegetation > aspect. The interaction detection of factors indicates that an interaction exists among evaluation factors, and no factors are independent of one another. In each soil layer of 0–50 cm, the interaction among evaluation factors has a two-factor enhancement and a nonlinear enhancement effect on soil gravimetric water content. This study contributes to the understanding of spatial heterogeneity and driving factors of soil moisture in alpine deserts, and guidance of artificial vegetation restoration and soil structure analysis of different desert types in alpine cold desert regions.

The vertical distribution understanding of undergrowth herbaceous plants in high altitude mountain areas is of great significance to reveal the environmental gradient change law of plant diversity. However, the species composition of herbaceous plants at different altitude gradients and the relationship between diversity and environmental factors is still vague. This study takes the Sejila Mountain in southeast Tibet at an altitude of 2,000–3,300 m as the study area to analyze the vertical distribution differences of the understory herbs and their driving factors on shady and sunny slopes. The results showed that: (1) The number of families, genera and species of herbaceous plants on sunny slope is greater than that on shady slope. Asteraceae on shady and sunny slopes has the largest number of species; (2) The α diversity index of the herbs on shady slope shows a U-shaped trend. The Cody heterogeneity index (β_C) is negatively correlated with the β diversity index. The herb richness index (R) on sunny slope is unimodal. The β diversity index displays the same as that of shady slope; (3) Different environmental factors have different effects on herb diversity. The correlation between environmental factors and diversity indicators indicates that there is a certain degree of clustering among samples. The environmental factors of shady slope and sunny slope are separated; and (4) The difference of water and heat conditions caused by altitude and slope aspect is an important driving factor for the diversity of herbage species, followed by soil clay content, silt content and slope gradient. This study will help to understand the species diversity and ecosystem characteristics of the region, and provide a reference for the study of plant community structure and function and rational utilization of understory plant resources in high-altitude mountain areas.

The intensifying global climate warming caused by human activities poses severe challenges to ecosystem stability. Constructing an ecological security pattern can identify ecological land supply and an effective spatial distribution baseline and provide a scientific basis for safeguarding regional ecological security. This study analyzes land-use data from 2000 to 2020 for Golog Tibetan Autonomous Prefecture. The PLUS model was utilized to project land-use potential for the year 2030. The InVEST model was employed to conduct a comprehensive assessment of habitat quality in the study area for both 2020 and 2030, thereby pinpointing ecological sources. Critical ecological restoration zones were delineated by identifying ecological corridors, pinch points, and barrier points through the application of the Minimum Cumulative Resistance model and circuit theory. By comparing ecological security patterns (ESPs) in 2020 and 2030, we proposed a dynamic restoration framework and optimization recommendations based on habitat quality changes and ESPs. The results indicate significant land-use changes in the eastern part of Golog Tibetan Autonomous Prefecture from 2020 to 2030, with large-scale conversion of grasslands into bare land, farmland, and artificial surfaces. The ecological security pattern is threatened by risks like the deterioration of habitat quality, diminished ecological sources as well as pinch points, and growing barrier points. Optimizing the layout of ecological resources, strengthening barrier zone restoration and pinch point protection, and improving habitat connectivity are urgent priorities to ensure regional ecological security. This study offers a scientific foundation for the harmonization of ecological protection and economic development and the policy development and execution of relevant departments.

Understanding the spatial distribution of herbaceous vegetation is critical for assessing how biodiversity may respond to climate change, particularly in high-elevation ecosystems. The Qinghai-Tibet Plateau in China is a hotspot of biodiversity research in the world, and the relationship between plant species distribution in alpine communities and topography and soils is understudied in the Anyemaqen Mountains in the northeast of the Qinghai-Tibet Plateau. This study investigates the patterns of α and β diversity of herbaceous plants and their key environmental drivers in the subalpine ecosystem of the Anyemaqen Mountains on the Qinghai-Tibet Plateau. Data on vegetation and environmental variables were collected across a gradient of 10 elevations ranging from 3600 to 4600 m during the 2021 growing season. Statistical analyses, including one-way ANOVA, redundancy analysis (RDA), and Monte Carlo significance tests, revealed significant differences between sunny and shady slopes in species composition and diversity. Species richness decreased with increasing elevation on sunny slopes, while the reverse trend was observed on shady slopes. Elevation and gradient were the most influential factors in both slope aspects, while soil thickness was significant on shady slopes. These findings contribute to understanding the environmental mechanisms that regulate biodiversity in alpine ecosystems and provide valuable insights for formulating conservation strategies in response to climate change.

Urban blue–green spaces (UBGSs) serve as irreplaceable ecological infrastructure that underpins ecosystem service provision and human well-being improvement in densely populated urban regions. Based on 10-year (2014–2023) Landsat 8 OLI remote sensing imagery, this paper systematically investigates the temporal–spatial evolutionary characteristics and potential socioeconomic and policy-related associations with UBGS changes in the Shandong Peninsula urban agglomeration (SPUA), a pivotal coastal urban agglomeration in eastern China. The results demonstrate that the total UBGSs in the SPUA exhibited a pronounced increasing trend throughout the study period: the area of urban green spaces (UGSs) expanded from 28,311.66 km² to 30,194.39 km², while urban blue spaces (UBSs) grew from 1108.02 km² to 1699.04 km². Concurrently, the ecological quality of UGSs has markedly improved, with NDVI showing a significant upward trend in over one-third of the built-up areas, and vegetation greenness in cities such as Binzhou, Jinan, and Zibo increasing by more than 35%. Landscape pattern analysis reveals that the spatial structure of UGSs has transformed from a fragmented and scattered distribution to a centralized and contiguous layout. Specifically, the aggregation index (AI) and largest patch index (LPI) increased overall, while the landscape shape index (LSI) decreased by approximately 18.3%, indicating that the connectivity and structural integrity of urban green spaces have been substantially enhanced. National strategic policies, particularly the outline of ecological protection and high-quality development planning for the Yellow River basin, have effectively alleviated the encroachment pressure of population agglomeration and economic expansion on UBGSs, and played a decisive regulatory role in promoting the structural optimization of blue–green spaces. These findings provide empirical evidence for cross-city collaborative planning and integrated ecological governance of blue–green spaces at the urban agglomeration level, and offer valuable reference for achieving sustainable urban development in other rapidly urbanizing areas.