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In recent decades, alpine meadows have experienced severe degradation owing to external disturbances. Although soil microorganisms are critical for ecosystem services, little is known about their responses to soil degradation and the potential patterns in alpine meadows. To solve this question, we collected and analyzed soil samples from three degraded alpine meadows situated on the Qinghai-Tibet Plateau. We aimed to examine the effects of degradation on soil microbial diversity and identify the ecological predictors for the diversity of bacteria and fungi. Our results showed that alpine meadow degradation significantly changed soil bacterial and fungal diversity and community composition. Specifically, the relationship between bacterial and fungal diversity and degradation intensity was a hump-shaped, with the highest diversity observed at a moderate degradation level. Additionally, alpine meadow degradation-induced changes in microbial diversity were strongly correlated with decreased plant production, with fungal diversity showing a closer link with below-ground biomass (BGB) than with bacterial diversity. Our findings offer empirical evidence that intermediate disturbance (i.e., moderate degradation) may be beneficial for supporting soil biodiversity. This has important implications for informing policy and management strategies meant to conserve soil biodiversity and ecosystem services when facing anthropogenic change.

In ecologically vulnerable regions with intricate land use dynamics, such as ecotones, frequent and intense land use transitions unfold. Therefore, the precise and timely mapping of land use becomes imperative. With that goal, by using principal component analysis, we integrated Sentinel-1 and Sentinel-2 data, using an object-oriented methodology to craft a 10-meter-resolution land use map for the forest–grassland ecological zone of the Greater Khingan Mountains spanning the years 2019 to 2021. Our research reveals a substantial enhancement in classification accuracy achieved through the integration of synthetic aperture radar–optical remote sensing data. Notably, our products outperformed other land use/land cover data sets, excelling particularly in delineating intricate riverine wetlands. The 10-meter land use product stands as a pivotal guide, offering indispensable support for sustainable development, ecological assessment, and conservation endeavors in the Greater Khingan Mountains region. [ABSTRACT FROM AUTHOR]

Under global change and climate variations, determining the impacts of climate change and human activities on cropland net primary productivity (NPP) in Bangladesh, India and Myanmar (BIM) is of great significance for identifying yield-limiting factors, making adaptive agricultural management plans, and improving yields. Based on the GLOPEM-CEVSA model, through an integration of remote sensing data and LAI simulation, we investigated the impacts and spatiotemporal changes of water and human activities on BIM from 1982 to 2015. Three types of cropland NPPs were considered: actual NPP (NPPA), NPP affected by temperature and water (NPPWT), and NPP only affected by temperature (NPPT). Our analysis revealed that the water factor plays a predominant role in determining the NPP level in the BIM. Temperature variability was found to be conducive to NPPT, exhibiting an increasing trend of 10.66 g C m–2 yr–1. However, this trend was partially offset by precipitation variability, resulting in a net increase of 0.96 g C m–2 yr–1. In comparing temperature-driven NPP to temperature and water-driven NPP, water stress caused NPPT to decrease by 65.46% compared to NPPWT for the entire region. Cropland NPP in northwestern India and the central Deccan Plateau were significantly affected by water stress. Moreover, the influence of water on NPP in the BIM exhibited a substantial upward trend from 1982 to 2015, with Myanmar experiencing the most significant increase. The gap between NPPWT and NPPA in BIM demonstrated a notable decreasing trend during the same period, underscoring the positive impact of human activities on NPP. Inferences drawn from our findings suggest that with the implementation of rational and efficient crop management practices, there is a 36.80% potential improvement in NPPA compared to NPPWT in the BIM region, with India and Myanmar showing potential increases of 39.20% and 38.29%, respectively. These insights provide guidance for practical measures aimed at water resource management to enhance cropland productivity in the BIM, and they present a methodology for quantifying the effects of climatic changes and human activities at a regional scale. [ABSTRACT FROM AUTHOR]