Search Results (346)

We introduce the Soil–Plant Coupling Principle (SPCP), a conceptual framework proposing that ecosystem stability emerges from the integrity of biological interactions rather than the condition of individual ecosystem components. Although current ecological assessments primarily rely on soil properties, plant performance, and microbial diversity, growing evidence indicates that ecosystems can remain apparently functional while progressively losing the coordination among processes that sustain resilience. This gap limits the ability of conventional diagnostics to capture interactional changes underlying early ecosystem vulnerability. Unlike ecosystem multifunctionality and resilience, which primarily describe the provision of multiple functions and the capacity to resist or recover from disturbance, respectively, SPCP focuses on the coordination among the processes that sustain these functions and resilience. SPCP reframes ecosystem degradation as progressive decoupling among carbon allocation, nutrient cycling, hydrological processes, and microbial interactions at the soil–plant interface. By integrating recent advances in soil ecology, plant physiology, microbiome science, ecological networks, and biogeochemistry, the framework provides a unified conceptual basis for understanding how interactional connectivity regulates ecosystem resilience. The objectives of this Perspective are to: (i) establish the theoretical basis for viewing ecosystem stability through soil–plant coupling; (ii) define the core dimensions of coupling integrity; and (iii) outline how coupling integrity could be operationalized using structural, functional, and interaction-based indicators. We further discuss the potential of coupling integrity as an early-warning property and identify key limitations and research needs for testing and validating the framework. By proposing an integrative and potentially testable framework, the manuscript provides a new lens for understanding ecosystem vulnerability and resilience across scales. Full article

Reservoirs, driven jointly by artificial regulation and natural processes, are semi-artificial complex ecosystems whose equilibrium states affect the water ecological security and management effectiveness of a river basin. Understanding how operational dispatch alters hydrodynamic processes, habitat structures, and biological succession pathways is necessary, as traditional steady-state theories based on natural lakes struggle to fully explain the responses of reservoir ecosystems. Therefore, this review constructs a theoretical framework for reservoir ecosystem regimes, defining the core connotation of their “conditional metastable state” as the long-term maintenance of physicochemical, biological, and hydro morphological parameters within limits that allow ecosystem functioning under anthropogenic regulation and natural disturbances. It identifies typical characteristics such as habitat reconstruction-driven dynamics, altered ecological resilience, dual threshold effects, and regulation-modified hydrological processes. We propose that reservoir regime shifts can be analyzed from three levels: the evolutionary sequence of the full life cycle, stage transitions during the operational period, and disturbance responses at multiple time scales. Full article

High-precision time-varying terrestrial absolute gravity observations provide a powerful tool for investigating mass redistribution processes within the Earth’s interior and at its surface. The southeastern margin of the Tibetan Plateau is a tectonically active region with frequent strong earthquakes, making accurate interpretation of local gravity observations critically important for earthquake prevention and disaster mitigation. Based on four epochs of absolute gravity measurements acquired using FG5(X) gravimeters at the Dongchuan station from 2017 to 2022, combined with co-located continuous GNSS vertical deformation data, a GLDAS Noah Land Surface Model, high-resolution remote sensing imagery, and forward numerical modeling, we performed quantitative corrections for crustal deformation and hydrological effects and analyzed the residual gravity variations. The results show that gravity change at the Dongchuan station exhibited an overall increasing trend with a maximum amplitude of 8.2 μGal during 2017–2022. While the 2017–2019 gravity changes were consistent with the combined effect of crustal vertical deformation and hydrological loading within uncertainty, a positive residual anomaly of several microGal remained after 2019, which was attributed to mass redistribution caused by nearby anthropogenic activities. This study confirms that the 2017–2022 Dongchuan observations meet the requirements for milliGal-level static gravity field research, with the 2017–2019 data suitable for time-varying gravity studies, while the post-2019 data require that gravity variations induced by anthropogenic activities in the vicinity of the station be accounted for when applied to such studies. Additionally, time-series high-resolution remote sensing can effectively identify hundred-meter-scale gravity disturbance sources near observatories, providing valuable support for gravity data interpretation and quality control. Full article

Against the backdrop of global climate change, wildfires have emerged as key disturbance factors accelerating permafrost degradation. However, how wildfires affect ground-surface deformation, including spatial patterns and potential driving mechanisms, remains unclear. Therefore, in this study, the permafrost region in the northern Da Xing’an Mountains affected by the catastrophic Great Black Dragon Fire (1987) is taken as a case study. On the basis of Sentinel-1 SAR imagery acquired from 2016 to 2021, the small baseline subset interferometric synthetic aperture radar (SBAS-InSAR) technique was employed to derive surface deformation rates. These rates were combined with historical fire severity (dNBR) and topographic factors. Random forest and spatial autocorrelation analyses were used to evaluate the long-term association between wildfire disturbance and surface deformation and its potential controls. The results indicate that (1) thirty-five years after the wildfire, vegetation in the permafrost region had not fully recovered to prefire levels; (2) surface deformation from 2016 to 2021 was dominated by subsidence overall. When unburned patches within the same region were used as controls for climate-driven background subsidence, the proportion of areas experiencing severe subsidence (annual rate ≤ −50 mm yr⁻¹) reached 12.86% in high-severity fire zones, compared with 10.21% in unburned areas, suggesting that high-severity fires may amplify regional background subsidence; and (3) the random forest model had low explanatory power (R² = 0.03) and was therefore used for exploratory comparison of the selected predictors rather than for accurate prediction of surface deformation. Among the selected variables, dNBR had the greatest relative importance, followed by terrain ruggedness and slope, whereas the remaining spatial variability may reflect unmeasured hydrological and subsurface controls. This study provides a quantitative basis for understanding the wildfire-induced “abrupt degradation” of permafrost, defined here as disturbance-driven acceleration of thaw and subsidence beyond gradual climate-driven degradation, and contributes to understanding carbon–climate feedback mechanisms in permafrost regions. Full article

Black-sand mining is an under-studied anthropogenic pressure on arid coastal environments, where sparse vegetation and slow natural recovery limit conventional impact assessment. Despite the recent expansion of heavy-mineral extraction along the Mauritanian coast, no spatio-temporal analysis has quantified its effects on land cover and surface-water dynamics in the N’Diago region. We analysed the N’Diago–LGUWYCHICH coastal sector (south-western Mauritania) using three Landsat scenes (2014, 2020, and 2026) in QGIS (free and open-source Geographic Information System), four spectral indices (NDVI-Normalized Difference Vegetation Index, NDWI-Normalized Difference Water Index, BSI- Bare Soil Index, and CI -Coloration Index), supervised Support Vector Machine classification and a 30 m SRTM Digital Elevation Model over a 97.82 ha area of interest. Bare soil dominated the landscape at every date (92.6–95.7%) and vegetation stayed below 7%, indicating that canopy-based metrics underestimate disturbance in this setting. The clearest change was hydrological: an inland water body shrank from 1.02 ha in 2020 to 0.40 ha in 2026, a 60.6% loss. This individual inland water body, measured directly and independently from the NDWI index, is our primary hydrological observation: the wet feature was smaller in the 2026 image than in the 2020 image and was located near the mapped concession areas, but the available data do not establish the cause of this change. Similar bare-soil and colour index values (BSI ≈ 0.23, CI ≈ 0.79–0.80) were observed in the processed images, while residual seasonal and radiometric differences between the Landsat 8 and DOS-corrected Landsat 9 products cannot be excluded; BSI and CI are treated only as candidate or contextual spectral patterns, so any delineation of the disturbed footprint is provisional and requires confirmation from independent field data. This study illustrates a low-cost exploratory workflow that may support preliminary monitoring in data-scarce arid coastal settings, pending validation with denser time series and field observations. Full article

Wetland ecosystems in large lake basins play a critical role in maintaining regional water security and ecological balance. Despite their importance, the long-term spatiotemporal dynamics of basin wetlands and their effects on lake water quality under intensive human disturbance remain elusive. This study leveraged multi-source satellite archives from 1986 to 2025 to construct a framework for extracting and classifying potential wetlands in the Chaohu Lake basin, Anhui province, China, and examined its evolution and its relationship with water quality. The resulting wetland maps are highly reliable, with overall accuracy ranging from 81.63% to 94.22% and precision approaching 99%, effectively addressing spectral confusion and boundary instability caused by hydrological fluctuations. In total, the basin contains approximately 2139.9 km² of potential wetlands (16%), which are spatially concentrated along the lake and river corridors. Over the 36-year period, wetlands underwent distinct phases of “relative stability—rapid decline—Emerging recovery,” with shrinkage primarily in the west and relative stability in the east, while ponds and paddy fields experienced the most frequent conversions. In recent years (2010–2025), changes in the water environment of Lake Chaohu showed strong spatiotemporal consistency with wetland dynamics. As partial wetland recovery emerged after 2015, concentrations of total nitrogen (TN), total phosphorus (TP), and chlorophyll-a (Chla) declined and stabilized, and the area affected by cyanobacterial blooms decreased by 46%, suggesting a potential role of wetland recovery in improving water quality and mitigating non-point-source pollution. This study provides a comprehensive characterization of wetland dynamics and their influence on water quality, offering valuable data and guidance for wetland conservation, ecological restoration, and integrated lake management in the Chaohu Lake Basin. Full article

Water scarcity strongly constrains the revegetation of disturbed mine substrates in cold-arid regions. This study compared soil-moisture dynamics between a microtopographic reclamation area and an adjacent flat reclamation area in an abandoned stone quarry within the Kalamaili Ungulate Nature Reserve, northwestern China. The integrated restoration treatment, established in 2018, combined linear trenches 30–40 cm deep and spaced 60 cm apart, native seed sowing, transferred seed-bank topsoil, and water-retaining material. From January to December 2024, sensor-derived apparent volumetric water content was monitored at five depths—0–10, 10–20, 20–30, 30–40, and 40–50 cm—at 10 min intervals using sensors operated with the manufacturer’s standard calibration. Following quality control and temporal synchronization, 41,475 valid timestamps were retained for each monitored profile. The study provides a continuous full-year, multi-depth record from an unirrigated, cold-arid reconstructed quarry substrate, a setting that remains underrepresented in previous micro-catchment and dryland-restoration research. However, this study is based on a single hydrological year and does not directly measure plant physiological responses or long-term restoration outcomes. Therefore, elevated soil moisture should be interpreted as a preliminary indicator of restoration potential rather than a definitive measure of ecological recovery success. The monitored microtopographic profile maintained higher mean apparent water content than the flat profile during most of the year. The largest annual relative profile difference occurred at 10–20 cm depth, reaching 18.0%, followed by 11.7% at 0–10 cm, whereas differences decreased below 20 cm and reached 1.9% at 40–50 cm. During selected rainfall and probable snowmelt periods, the microtopographic profile exhibited larger wetting responses and slower post-event recession. These patterns indicate contrasting upper-profile wetting and drying dynamics between the two monitored reclamation configurations. However, runoff, infiltration, evaporation, snow accumulation, soil-water potential, and vegetation responses were not measured directly. Moreover, monitoring began several years after vegetation establishment, and trenching, seed addition, seed-bank transfer, and water-retaining material were not evaluated independently. The findings should therefore be interpreted as a site-specific post-establishment comparison rather than evidence of the isolated effect of microtopography. Replicated, multi-year studies are required to determine the mechanisms, effectiveness, and broader transferability of this integrated reclamation configuration. Full article

Western Siberia is one of the largest high-latitude lowland peatland regions on Earth and stores vast amounts of organic carbon in landscapes where vegetation, hydrology and fire are strongly regulated by permafrost. However, the long-term interactions among fire disturbance, permafrost dynamics, peatland development and forest–mire vegetation change remain insufficiently resolved. Here, we reconstructed regional vegetation dynamics, local mire succession, permafrost evolution and fire activity in the subarctic Pur–Taz interfluve, Western Siberia, during the Early to Middle Holocene from 11.2 to 4.4 cal kyr BP. The study combines pollen, non-pollen palynomorphs, microcharcoal records, principal component analysis and comparison with modern surface-sample analogues. The record documents a transition from Early Holocene larch–birch forest-tundra with no close modern analogue to increasingly heterogeneous forest–mire and shrub-tundra landscapes. After 9.5 cal kyr BP, Betula pubescens declined and Picea obovata pollen increased, with the strongest spruce signal between ca. 5.5 and 4.7 cal kyr BP. However, this pattern did not necessarily reflect a uniform regional expansion of spruce. Integrated fire reconstruction, based on microcharcoal peaks, Gelasinospora-type and declines in Betula pubescens-type pollen, indicates that recurrent fires after 8.0 cal kyr BP preferentially affected well-drained birch–larch uplands, whereas wetter riparian habitats acted as refugia for spruce. This landscape contrast increased the relative contribution of Picea pollen from fire-protected valleys, producing an apparent, partly artefactual spruce expansion signal. Locally, an open lake present at 11.2 cal kyr BP was transformed into a peatland after ca. 9.7 cal kyr BP. Cooling associated with the 8.2 cal kyr BP event promoted permafrost aggradation and polygonal mire initiation, whereas subsequent thaw and subsidence favoured waterlogging and mesotrophic fen development. Repeated alternation between permafrost aggradation, oligotrophication, degradation and renewed waterlogging culminated in polygonal microrelief by 6.1–5.3 cal kyr BP. These results show that Holocene vegetation change in the Pur–Taz interfluve was not controlled by climate alone, but by spatially heterogeneous feedbacks among permafrost state, peatland hydrology, fire disturbance and pollen-source structure. The West Siberian record provides a palaeoecological analogue for anticipating nonlinear vegetation and fire-regime responses in permafrost lowlands under ongoing Arctic warming. Full article

The Huaibei region is a critical grain and energy–chemical base in northern China, characterized by substantial water demand for industrial and agricultural production. Karst groundwater systems constitute the primary water supply source in this area. Under the superimposed impacts of intensive exploitation, climate change, and anthropogenic activities, karst aquifers have encountered a series of geo-environmental problems, including groundwater level decline and expansion of cones of depression. Most previous studies have predominantly focused on water quality assessment and groundwater resource quantification, yet systematic investigations into the multi-scale characteristics and driving mechanisms of karst groundwater level dynamics remain insufficient. In this study, based on long-term groundwater level and rainfall monitoring data (2014–2024) from three monitoring wells representing different types of karst aquifers, continuous wavelet transform (CWT) and wavelet coherence (WTC) approaches are introduced to identify the periodic patterns of karst groundwater levels and reveal the dominant controlling factors of groundwater level dynamics. The results demonstrate that groundwater levels in all types of karst aquifers exhibit distinct multi-scale periodic variations. The groundwater levels of HB01 and HB02 share dominant oscillation periods of 18~19 months and 9 months with regional rainfall, while the groundwater level at HB03 displays a more complex, multi-scale, periodic combination of 41 months, 18~19 months, and 9 months. Periodic variations in regional rainfall serve as the dominant controlling factor for the intra-annual and inter-annual periodic fluctuations of karst water levels, with a prominent resonance relationship identified between the two variables at dominant periodic scales. Distinct heterogeneity is observed in the response magnitude and lag time of different karst aquifer types to rainfall; specifically, the lag time of water level response to rainfall on the annual periodic scale ranges from 2.7 to 2.9 months. The correlation between annual average water level and pumping discharge is moderate for boreholes HB01 and HB03, whereas a strong correlation is detected for borehole HB02, implying that its water level regime is likely subjected to pronounced pumping disturbance. The degree of karst development, aquifer burial depth, and overlying stratum architecture are the key geological factors accounting for such heterogeneous response patterns. For the first time, this study utilizes long-term water level time series data from the karst water exploitation zone of the Huaibei Plain, complemented by synchronous precipitation and pumping records. Integrated with regional hydrogeological settings, wavelet analysis is employed to conduct an in-depth investigation into the dynamic variations in karst water levels in the Huaibei region from the perspective of groundwater recharge–discharge relationships. The results provide a scientific underpinning for the remediation of karst water over-exploitation and the optimal allocation of water resources. Specifically, pumping and artificial recharge schemes can be proactively adjusted based on periodicity forecasts. Zoned management strategies for water resources are put forward: artificial regulation and storage are recommended for zones with sensitive hydrological responses, while preventive protection is prioritized for zones with sluggish responses. By incorporating periodic characteristics and lag durations, targeted pumping strategies for dry and wet seasons can be developed, and a coupled water level–rainfall–pumping early warning system can be established to realize the long-term sustainable regulation of karst water resources. Full article

Winter imposes severe ecological constraints on Eurasian otters (Lutra lutra), yet the environmental characteristics of their winter marking sites remain poorly understood. We characterized winter sprainting sites along a human disturbance gradient in Changbai Mountain, northeastern China. In January 2025, 55 sites were recorded along three rivers and assigned to urban or wild river-reach contexts based on the broader spatial and management context of each reach. We measured topographic, hydrological, riparian, fish-diversity, and anthropogenic variables. Broad environmental gradients were summarized using Factor Analysis of Mixed Data (FAMD), and five local variables were compared between river-reach contexts using exploratory tests with Holm adjustment. Of the 55 sites, 54 were beside flowing, unfrozen water. Intermediate-to-deep water, natural banks and forested riparian backgrounds were common. The first two FAMD dimensions explained 52.5% of environmental variation, representing a spatially coupled gradient involving anthropogenic remoteness and river-section fish resource background, and a topographic and channel-structure contrast. Urban and wild sites differed in water depth, bank type, and vegetation cover, while sprainting sites occurred in both. These findings show that winter marking activity was concentrated within accessible river sections embedded in contrasting landscape contexts. Full article

Karst river basins require restoration approaches that identify vulnerable connections while distinguishing ecological constraints from governance implementation conditions. This study developed a sequential Structure–Resistance–Connectivity–Governance (SRCG) framework for the Chengjiang River Basin, Guangxi, China. Ecological sources were identified from vegetation vitality, habitat quality, landscape integrity, and hydrological proximity. Natural landscape resistance and anthropogenic disturbance were integrated to delineate potential source-pair corridors. Bottleneck Intensity combined corridor load, minimum corridor width, and high-resistance overlap, and was integrated with ecological movement resistance to delineate Ecological Restoration Priority Zones (ERPZs). Governance Mismatch Index and Administrative Boundary Proximity Index values were applied only after ERPZ delineation. The analysis identified 28 ecological sources covering 312.4 km², 76 potential connections, three principal bottleneck clusters, and six ERPZs covering 118.5 km². The upper basin retained a relatively continuous network; whereas, the middle and lower reaches were increasingly constrained by roads, settlements, quarry disturbance, fragmented cropland, and discontinuous riparian vegetation. ERPZ-A, D, E, and F were resistance-dominated, ERPZ-B was bottleneck-dominated, and ERPZ-C was compound-priority. Governance assessment differentiated four implementation contexts. Overall land-cover accuracy was 0.896, Cohen’s kappa was 0.874, and 14 of 16 field sections were concordant with mapped landscape conditions; sensitivity tests retained the principal sources, bottlenecks, and ERPZ cores. The framework separates ecological restoration urgency from implementation difficulty, while its outputs represent potential structural rather than confirmed functional connectivity. Full article

Mangrove forests provide essential ecosystem services but are increasingly threatened by anthropogenic pressures and climate-related disturbances. Effective and accessible tools for assessing mangrove ecosystem condition are therefore needed to soundly support their conservation and management. This study adapted the “Coastal Health” framework originally proposed for assessing coastal ecosystems health to evaluate the health status of mangrove forests along the Caribbean coast of Colombia. Using freely available high-resolution imagery from Google Earth Pro 7.3, complemented by field observations, technical reports, and unpublished literature, 56 mangrove sites distributed across eight coastal departments were assessed according to their ecological integrity, hydrological connectivity, sediment dynamics, freshwater and marine inputs, mangrove species condition, and their potential for landward and seaward migration. The results showed that 54% of the evaluated sites were classified as being in “Good Health”, while 2% were categorized as “Health Warning”, 3% as “Surface Wounds”, 14% as “Minor Injury”, 25% as “Major Injury”, and 2% as “Deceased”. Mangroves in good condition were generally associated with protected areas, river mouths, estuaries, and relatively isolated coastal systems, whereas degraded ecosystems were affected by urban expansion, tourism infrastructure, hydrological alterations, coastal engineering works, and reduced freshwater inputs. The proposed methodology proved to be a simple, low-cost, and easily replicable tool for large-scale mangrove health assessment. It provides valuable information for prioritizing conservation and restoration actions and can be adapted to support mangrove monitoring and ecosystem-based coastal management in other regions worldwide. Full article

Purpose: To address the measurement inaccuracies of weighing-type rain gauges caused by environmental disturbances such as vibration, temperature drift, and creep, this study aims to develop a robust error modeling and compensation framework adaptable to complex conditions. Method: A nonlinear error model was constructed by analyzing multi-source disturbance factors and incorporating both linear and nonlinear temperature terms. A BP neural network was employed to compensate for complex error patterns, and several intelligent optimization algorithms (a genetic Algorithm (GA), a particle swarm algorithm (PSO), and a GOOSE algorithm (GOOSE)) were used to enhance training performance. An improved adaptive GOOSE algorithm (ADGOOSE) was further proposed to optimize the BP network by integrating dynamic control coefficients and perturbation-based restart strategies. Results: Experiments under various rainfall intensities and temperatures demonstrated that the ADGOOSE-BP model outperformed traditional filtering and other optimization methods, achieving the lowest RMSE of 0.0494 and the highest R2 of 0.9835. Conclusion: The proposed method effectively models and compensates for environmentally induced errors in weighing rain gauges, demonstrating strong potential as a high-precision, adaptive compensation framework that provides a solid foundation for future field-deployable hydrological monitoring systems. Full article

Freshwater resources constitute a fundamental component of coupled natural–human systems, underpinning ecosystem functioning, biogeochemical cycling, and socio-economic development. Anthropogenic climate change (i.e., climate change attributable to human activity, as distinct from natural climatic variability), driven primarily by greenhouse gas emissions and land-use change, is exerting significant pressure on the global hydrological cycle, resulting in increased hydroclimatic variability, intensification of extreme hydrometeorological events, and progressive degradation of freshwater quality and availability. This review synthesizes recent scientific evidence on climate-induced impacts on water systems together with emerging adaptation and resilience strategies. The analysis is based on a systematic assessment of 100 peer-reviewed studies indexed in the Web of Science Core Collection (2010–2025) and synthesized following a PRISMA-informed (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) narrative review protocol. Beyond confirming well-established trends in precipitation regimes, cryospheric decline, increasing evapotranspiration, and the growing frequency of droughts and floods, this review quantifies the magnitude of these changes across the reviewed literature, including an approximately 134% increase in flood-related disasters since 1980 and a 29% increase in drought duration since 2000. More importantly, it provides an integrated synthesis that links physical climate impacts with adaptation strategies and socio-ecological resilience frameworks within a unified analytical perspective, thereby complementing previous domain-specific reviews that have generally examined these dimensions separately. Prominent adaptation pathways identified across the reviewed literature include nature-based solutions, integrated water resources management frameworks, and the deployment of digital water technologies. In parallel, resilience is increasingly conceptualized as the adaptive capacity of socio-hydrological systems to absorb disturbances, reorganize, and transform under changing climatic conditions. The findings highlight the need to strengthen integrated and cross-sectoral water governance, enhance climate-informed decision-making, and expand monitoring and data infrastructures to improve long-term water security and socio-ecological resilience under accelerating climate change. Full article

Tugai forests represent key riparian ecosystems of the arid landscapes of Central Asia, where vegetation dynamics are strongly influenced by seasonal hydrological variability and increasing anthropogenic pressure. Assessing the population structure of dominant shrub species can provide important insights into the condition and resilience of these floodplain ecosystems. This study examines the demographic structure, vitality, and morphological variability of Lycium dasystemum populations in the Syr Darya River valley. Field surveys were conducted in six subpopulations located in Tugai forests differing in hydrological conditions and levels of anthropogenic disturbance. Population structure was assessed using ontogenetic spectra, ecological density, and regeneration indices, while vitality indices and morphological traits were analyzed to evaluate population condition and phenotypic variability. Species turnover dominated β-diversity patterns (βsim up to 81%), indicating floristic differentiation among the studied communities. Clear spatial differences in demographic parameters were detected among subpopulations. Subpopulations occurring in relatively stable habitats showed more balanced ontogenetic spectra, higher vitality indices, and signs of active regeneration, whereas subpopulations exposed to stronger anthropogenic pressure were characterized by demographic imbalance, reduced recruitment, and lower ecological density. Morphological analyses revealed moderate phenotypic plasticity, suggesting that some traits may be associated with local floodplain habitat conditions. These findings indicate that maintaining suitable floodplain moisture conditions and regulating grazing pressure may contribute to the persistence of L. dasystemum populations and the conservation of Tugai vegetation in the Syr Darya basin. Full article