As a vital ecological security barrier and climate regulator in northwestern China, the spatial patterns and evolving formation mechanisms of ecosystem services within the Qinghai Lake basin hold significant strategic value for ecological conservation and national park development in the region. This study selected land use data during 2000–2020, integrating the equivalent factor method, spatial correlation analysis, and the geodetector approach to systematically investigate the spatial heterogeneity characteristics of ESV in the Qinghai Lake basin and its corresponding driving mechanisms. The results indicate the following: (1) During the period 2000–2020, grassland consistently constituted the primary land cover category within the Qinghai Lake Basin, accounting for over 60% of the total area; water bodies (16.67%) and unused land (16.56%) represented the secondary land use categories. Over this twenty-year period, the total ESV exhibited a slight increasing trend, rising from USD 30.30 × 10⁸ to USD 30.75 × 10⁸, representing a growth of 0.31%. Regulating services constituted the primary component of ESV. The highest contribution to ESV originated from water bodies, with grassland ranking second. (2) ESV displayed a spatial arrangement marked by “high values in the lake center and low values in the surrounding areas” and “higher values in the southeast and lower values in the northwest.” Its spatial correlation exhibits a pronounced positive relationship. The number of units classified as high-high clusters (primarily water bodies at low elevations) and low-low clusters (mainly grasslands and unused land at high elevations) both increased over the study period, indicating a continuous intensification of ESV spatial agglomeration. (3) Results from the geographical detector reveal that both natural and anthropogenic factors collectively drive the spatial variation in ESV, with natural factors exhibiting stronger explanatory capacity. Among these, elevation and temperature are identified as the dominant drivers of ESV spatiotemporal differentiation. The combined effect of two interacting factors surpasses the influence exerted by any single factor in isolation. This research clarifies that the spatial distribution of ESV in the Qinghai Lake Basin, which features “high values in the lake center and low values in the surrounding areas” as well as “higher values in the southeast and lower values in the northwest,” is jointly shaped by the combined control of vertical zonality governed by topographic and climatic factors and the spatial differentiation of human activities. In low-altitude lakeshore zones, ESV rose as a consequence of water body expansion and the enforcement of ecological conservation measures, leading to the emergence of high-value clusters. In contrast, ESV improvement in high-elevation regions remained limited, constrained by fragile natural conditions and minimal human intervention. The insights derived from this research offer a scientific foundation for refining the “one core, four zones, one ring, multiple points” functional zoning framework of the Qinghai Lake National Park, as well as for developing tailored management approaches suited to distinct elevation-based regions.

The Qinghai Lake Basin represents a critical ecological security barrier in the northeastern Qinghai–Tibet Plateau. Water yield and carbon storage within this basin are closely linked to regional ecological security and sustainable development. To investigate their spatiotemporal patterns, influencing factors, and spatial interrelationships from 1995 to 2020, this study integrated the InVEST model, the Optimal Parameter Geodetector model, and spatial autocorrelation analysis. The results indicate that water yield exhibited a fluctuating yet generally increasing trend over the study period, rising from 1.42 × 10⁹ m³ to 1.97 × 10⁹ m³. High water yield values were predominantly concentrated in high-altitude headwater areas, whereas low values mainly occurred in the lake area and its surroundings. Elevation, annual mean temperature, and precipitation were identified as the primary drivers of water yield. Carbon storage increased from 1.76 × 10⁸ t in 1995 to 2.14 × 10⁸ t in 2020. High carbon storage values were mainly concentrated in grassland and forested areas, while low values were largely distributed in built-up land, unused land, and the lake area. Elevation, NDVI, and water yield emerged as the main influencing factors of carbon storage. A significant positive spatial correlation was observed between water yield and carbon storage. Persistent patterns of high-carbon-storage–high-water-yield clusters and low-carbon-storage–low-water-yield clusters demonstrate a clear spatial synergy. These findings provide scientific support for ecological conservation, water resource management, and carbon sink enhancement in the Qinghai Lake Basin and are of practical significance for sustaining regional ecosystem services and safeguarding sustainability.

Poa alpigena Lindm is a dominant forage grass in the temperate grasslands of the Qinghai Lake Basin, commonly used for grassland restoration. Soil microorganisms are crucial in material cycling within terrestrial ecosystems. This study aimed to investigate the effects of P. alpigena on the microbial community composition and structure in rhizosphere and non-rhizosphere soils in the Qingbaya grassland area. Using high-throughput sequencing, we identified microbial gene pools and compared microbial diversity. Metagenomic analysis showed that non-rhizosphere soil contained 35.42–36.64% known microbial sequences, with bacteria making up 79.25% of the microbiota. Alpha diversity analysis indicated significantly higher microbial richness and diversity in non-rhizosphere soil, influenced by electrical conductivity, total carbon, and total nitrogen content. LEfSe analysis revealed that Alphaproteobacteria and Betaproteobacteria were major differential taxa in rhizosphere and non-rhizosphere soils, respectively. Key metabolic pathways in rhizosphere microorganisms were related to AMPK signaling, secondary metabolite biosynthesis, and starch metabolism, while non-rhizosphere microorganisms were involved in aromatic compound degradation, purine metabolism, and microbial metabolism in diverse environments. The enrichment of microbial taxa and functional pathways related to methane oxidation in rhizosphere soil suggests a potential role of P. alpigena in shaping microbial processes linked to greenhouse gas regulation, although direct evidence of methane flux changes was not assessed. Similarly, the presence of aromatic compound degradation pathways in non-rhizosphere soil indicates microbial potential for processing such compounds, but no direct measurements of specific contaminants were performed.

Lake-level rise driven by changing precipitation is increasing inundation in littoral wetlands, but responses of cbbL-harboring carbon-fixing microorganisms remain uncertain. A controlled soil-column experiment included four hydrological regimes: unflooded soil (CK), water level aligned with the soil surface (S0), and standing-water depths of 10 cm (S10) and 20 cm (S20). Amplicon sequencing of cbbL showed that the Shannon index was significantly higher in S20 than in CK (p = 0.0394), whereas Simpson, Chao1, and ACE did not differ significantly among treatments. Overall amplicon composition also lacked a significant treatment effect (PERMANOVA: R² = 0.344, p = 0.112). Pseudomonadota represented 96.9–97.7% of taxonomically assigned sequences and remained dominant across treatments, although several genera varied in relative sequence proportion. Exploratory LEfSe screening identified Rhodoblastus-, Hydrogenophaga-, and Azospirillum-related lineages as candidate indicators of CK, S10, and S20, respectively. Multivariate soil profiles did not differ significantly among treatments (PERMANOVA: R² = 0.374, p = 0.220). After collinearity filtering, EC had the highest normalized mean absolute out-of-fold SHAP contribution among EC, pH, and TC (43.8–59.1%). However, outer leave-one-out cross-validation produced negative predictive R² values (−0.43 to −0.11), indicating limited model generalizability. Overall, S20 was associated with higher Shannon diversity than CK, while Pseudomonadota remained dominant and several genera varied in relative sequence proportion. EC should therefore be regarded as an exploratory candidate correlate of cbbL alpha diversity rather than a validated environmental driver, and this association requires further evaluation under natural hydrological conditions.

As a vital ecological security barrier and climate regulator in northwestern China, the Qinghai Lake Basin (QLB) holds significant strategic value for regional ecological conservation and national park development. This study, utilizing land use data from 2010 to 2023 and integrating the InVEST and GeoDetector models, systematically investigated the spatiotemporal dynamics of soil conservation (SC) and its underlying driving mechanisms. The results indicate the following: (1) During the study period, SC services exhibited a gradual declining trend across the selected years, with total SC decreasing from 14.64 × 10³ t to 7.49 × 10³ t. Spatially, high-value areas were predominantly concentrated in the high-altitude forest–grassland ecotones along the basin margins, whereas low-value areas were mainly distributed in the low-altitude zones surrounding the lake and in the northwestern corner of the basin. (2) Among different land use types, forestland, bare land, and grassland constituted the dominant contributing categories, with bare land exhibiting the highest sediment export (SE) intensity (ranging from 8.93 to 19.13 t·hm⁻²·a⁻¹), thereby serving as the primary erosion source area. Along the elevational gradient, the mid-to-high elevation zones (3500–4500 m) contributed the most to total SC, with SC intensity increasing progressively with rising elevation. With respect to slope classes, total SC was predominantly concentrated in the gentle-to-moderate slope zones (5–25°), whereas SC intensity exhibited a non-linear increase with increasing slope steepness. (3) Slope was identified as the single factor with the strongest explanatory power regarding the spatial heterogeneity of SC, and the coupled interactions of “topography–soil–vegetation” exerted a synergistic regulatory effect on SC function. It is recommended that priority attention be given to the mid-to-high elevation contribution zones (3500–4500 m), the total SC contribution zones on gentle-to-moderate slopes (5–25°), and the extremely steep slope areas (>35°) with high erosion risk, so as to implement differentiated soil and water conservation measures. These findings provide a scientific basis for ecological protection, soil and water conservation strategy formulation, and sustainable development in the QLB.