Search Results (1,718)

Reservoir drawdown zones are repeatedly affected by water-level fluctuations and anthropogenic regulation, making vegetation recovery an important issue for ecological restoration and sustainable reservoir management. This study focused on Cynodon dactylon, a dominant herbaceous species in the drawdown zones of five reservoirs in the Jinsha River Basin, southwestern China. Drawing on the existing concept of stress memory, which emphasizes the retained effects of previous environmental stress exposure on subsequent plant responses, we established an integrated assessment framework based on species dominance, functional traits, landscape pattern indices, and the soil seed bank. This framework was used to evaluate variation in the stress memory of C. dactylon across different successional stages and inundation gradients. The results showed that the overall stress memory of C. dactylon increased with successional progression in both the upper and lower zones, indicating continuous adaptive accumulation under long-term hydrological disturbance. The memory reflected by individual component indicators also generally increased, although their accumulation patterns varied among indicators. These findings suggest that dominance, functional traits, landscape pattern, and the soil seed bank can jointly characterize the adaptive responses of C. dactylon during vegetation recovery. Overall, the stress memory framework provides a systematic approach for identifying stage-specific vegetation changes, evaluating restoration potential, and informing ecological restoration and sustainable management in reservoir drawdown zones. Full article

Reservoirs supplying urban areas are often managed according to their primary function, which may constrain ecological functioning. This paper presents a multiscale environmental assessment of the Serra Serrada Reservoir, NE Portugal, to identify environmental pressures and mitigation measures across landscape, catchment, reservoir-surroundings, reservoir, and urban scales. The assessment was based on field observations, available site-specific information, and technical data. Key pressures included marginal habitat disturbance, seasonal water-level fluctuations, drawdown-zone exposure, and urban water demand. Among the mitigation measures identified, urban water-efficiency interventions were further examined as a demand-side response in selected public buildings. These buildings accounted for about 31,500 m³ of annual water consumption, with potential savings of 1.5–74.4%. The case study highlights the value of linking environmental mitigation with urban water-efficiency measures. Full article

The invasive plant Datura stramonium L. possesses strong reproductive capacity and ecological adaptability, showing a tendency to spread rapidly, especially in highly human-disturbed habitats. To explore its resource utilization pathway—turning waste into wealth—and to address toxic metal pollution in strongly human-disturbed areas (such as mining regions), this study evaluates its phytoremediation potential in contaminated soils on the Qinghai–Tibet Plateau. We established a non-planted control and three planting density treatments to compare the removal rates of Pb, Cd, Cr, and As. To our knowledge, this is the first study to assess how planting density influences the multi-metal phytoremediation performance of this invasive species in a high-altitude plateau environment. The results showed that planting significantly increased toxic metal removal rates, with overall efficiency generally improving at higher densities, particularly for Cr. Analysis of bioconcentration and translocation factors revealed distinct element-specific accumulation patterns. Pb and As were primarily enriched and retained in the roots. Interestingly, while Cd exhibited a strong localized tendency to accumulate in the leaves, its overall root-to-shoot translocation remained relatively restricted at the whole-plant level, similar to Cr. Overall, D. stramonium functions primarily through root stabilization for Pb, As, and Cr, alongside partial aboveground accumulation for Cd. However, given its toxic and invasive nature, any practical phytoremediation application requires strict post-harvest biomass management and ecological monitoring to prevent secondary spread. Full article

The Dwarf Ombú, Phytolacca tetramera, is a rare and highly unusual plant endemic to the northeastern Pampean grasslands of Argentina and is currently considered of high conservation priority. In order to better understand its biology, ecology, and conservation requirements, we studied its anatomy, reproductive traits, life history, and distribution based on field observations and herbarium material. Our results show that P. tetramera possesses a combination of traits consistent with the concept of ecological anachronism. The species produces large fleshy fruits whose size and shape are comparable to those interpreted as adapted for dispersal by extinct megafauna. In addition, the plant exhibits morphological and ecological adaptations associated with intense grazing, trampling, and drought tolerance, including robust underground structures and a growth pattern comparable to underground trees from seasonally dry open habitats. These findings suggest that P. tetramera evolved under ecological conditions markedly different from those existing today, including megafaunal disclimax environments that disappeared after the late Pleistocene extinctions. This ecological mismatch may help to explain its present rarity, fragmented distribution, and low population numbers. Our results also indicate that current conservation strategies for P. tetramera should consider the role of disturbance regimes and extinct ecological interactions in shaping the biology of this species. Full article

Herbicides considered selective to rice are generally evaluated based on their direct crop safety and weed suppression effects, yet it remains unclear whether they may also trigger indirect or context-dependent effects on rice under rice–barnyardgrass co-cultivation. To address this question, we compared rice performance and associated microbial dynamics under six conditions: rice–barnyardgrass co-cultivation and rice monoculture, each treated with a water spray control or sublethal doses of propanil (Pro, 66.7 mg a.i. L⁻¹) or cyhalofop-butyl (Cyh, 5.86 mg a.i. L⁻¹). Barnyardgrass exhibited visible injury and stronger leaf-level oxidative stress responses, whereas rice displayed no discernible phytotoxic symptoms. Nevertheless, under co-cultivation, herbicide treatment significantly suppressed rice growth, with up to 17.8% lower root lengths and 24.8% lower shoot fresh weights, with reductions varying by herbicide and trait. By contrast, comparable suppression was not observed under herbicide exposure or co-cultivation alone, identifying this response as an emergent, context-dependent negative effect. Microbiota reassembly emerged as an early and stage-specific component of the herbicide-associated response under co-cultivation, with the most pronounced changes detected on day 5 and occurring primarily in bacterial communities. Moreover, bacterial community variation was negatively correlated with root length (ρ = −0.664), and urease activity declined under herbicide treatment. Together, these findings indicate that in paddy fields, herbicides act not only on individual plants but also as an external disturbance to the coupled rice–barnyardgrass system, for which microbiota reorganization represents a key component of the ecological response. Our results suggest that herbicide selectivity should be interpreted within a crop–weed–microbiome context, rather than being inferred solely from their direct crop safety and weed suppression effects. Full article

The construction of green mines is a core strategy for promoting ecological civilization in China’s mining sector, yet its long-term ecological effects require quantitative assessment. Using a cement-grade limestone mine operated by Linyi Zhonglian Cement Co., Ltd. in Shandong Province as an illustrative case, we employed Landsat 8 OLI/TIRS imagery acquired in 2015, 2020, and 2025 to develop a five-indicator framework for assessing ecological environment quality. The selected indicators comprised greenness (NDVI), wetness, dryness (NDBSI), land surface temperature (LST), and dust concentration (MECDI). These five indicators were subsequently integrated via principal component analysis to generate the Mine Ecological Quality Index (Mine-EQI). Using this index, we applied the Theil–Sen median slope estimator alongside zonal statistics to examine ecological change trajectories across the full study area and three functional zones—the industrial square, haul roads, and active mining area—over the 2015–2025 period. The ecological outcomes attributable to the green mine policy were then quantified. The results show that (1) the mean Mine-EQI of the study area decreased from 0.3713 in 2015 to 0.3460 in 2025, exhibiting a slight overall decline. However, the rate of decline decreased from −6.1% during 2015–2020 to −0.7% during 2020–2025, yielding a Temporal Change Intensity index (TCI) of +88.5%, indicating that the ecological degradation trend has been effectively curbed. (2) Significant spatial heterogeneity was observed. The industrial square showed substantial improvement (Theil–Sen slope = +0.0726), while the haul roads (slope = −0.0705) and mining area (slope = −0.0408) continued to exhibit degradation trends. The improved areas (9.7% of the study area) were spatially coincident with green mine engineering projects. (3) The dust indicator (MECDI) decreased by 24.7% during 2020–2025, and the vegetation index (NDVI) increased by 19.5% over the decade, representing the dominant contributors to ecological improvement. This study reveals that China’s green mine policy has yielded remarkable ecological improvements in relatively stable functional zones such as industrial squares. In contrast, ecological restoration within persistently disturbed areas, including haul roads and mining pits, demands long-term sustained investment and governance. By integrating remote sensing techniques with policy analysis, this research establishes a replicable framework for evaluating progress toward sustainable mining practices. The findings directly support the monitoring of SDG 12 (Responsible Consumption and Production) and SDG 15 (Life on Land), providing a quantitative pathway to balance mineral resource extraction with ecological protection—a core sustainability challenge for resource-dependent regions. Full article

Runoff on the Chinese Loess Plateau has declined substantially over recent decades, but the relative roles of climate change and non-climatic disturbance remain debated. Here, we provide a robust regional attribution of runoff reduction across 14 major catchments during 1961–2009 by integrating seven Budyko-based climate elasticity methods with long-term hydro-meteorological analysis and change-point detection. Across the region, runoff and runoff coefficients decreased markedly, while evapotranspiration and leaf area index increased, indicating a widespread reduction in catchment water yield. Runoff showed consistently greater sensitivity to precipitation than to potential evapotranspiration, highlighting precipitation as the primary climatic control on runoff variability. However, the Budyko-based climatic component explained only part of the observed runoff decline, and the residual component not explained by annual precipitation and potential evapotranspiration was large in many catchments, with estimated contributions generally exceeding 50% and reaching more than 80% in several basins. Independent evidence, including vegetation greening, the expansion of ecological engineering measures, and increasing anthropogenic water demand, suggests that this residual was at least partly associated with human disturbance, although other non-Budyko climatic and hydrological processes may also contribute. These results indicate that annual precipitation and potential evapotranspiration alone cannot explain runoff decline across much of the Loess Plateau and underscore the need to jointly consider climatic forcing, land surface alteration, and direct human water use in regional water management. Full article

The Lhalu Wetland National Nature Reserve, the largest natural urban wetland on the Qinghai–Tibet Plateau, plays a critical role in maintaining regional ecological balance and biodiversity. However, the baseline biodiversity of this reserve remains unclear because of the extensive temporal span of historical records, shifts in taxonomic systems, and inconsistent survey methodologies, which impedes a robust scientific understanding of its ecological dynamics. This study systematically compiled and taxonomically verified species records from over 50 sources spanning the 1950s to the present. The records cover plants, fish, birds, and amphibians/reptiles, thereby resolving issues of synonyms, homonyms, and misidentifications. Each species record is annotated with its original survey time, allowing users to distinguish historically reported occurrences from those recorded in recent surveys. Species accumulation curves were constructed for major taxa and compared with 45-year climatic trends (1979–2023) and socioeconomic indicators for Lhasa City. A total of 438 vascular plant species (82 families, 251 genera) and 311 animal species (39 orders, 98 families), including 30 fishes, 174 birds, and 11 amphibians/reptiles, were documented. Invasive species comprised 55 alien plants and 13 alien fishes, while 4 plant and 46 animal species are under national protection. Temporal synchrony between increases in alien taxa and anthropogenic pressures (gross domestic product (GDP) and population growth, infrastructure development) suggests that human activities may be a potential driver of biodiversity change, but formal causal inference is precluded by heterogeneity in survey methods and sampling effort. This work provides a structured dataset of the biodiversity baseline of the Lhalu Wetland and offers a descriptive assessment of its temporal patterns in relation to climate and human disturbance, while explicitly acknowledging data limitations. It provides essential data and theoretical support for the scientific management and targeted conservation of plateau urban wetlands. Full article

Shallow lakes in the Yangtze River Delta are characterized by fragile ecosystems, strong sediment–water interactions, and poor resistance to pollution shocks; they are prone to shift from macrophyte-dominated clear-water states to phytoplankton-dominated turbid states under intensive human disturbance. To improve the efficacy of aquatic ecological restoration, this study takes a typical shallow urban lake—Kuilei Lake in Kunshan—as the research object, and establishes a two-dimensional hydrodynamic and water quality model to simulate the temporal and spatial variations in flow fields, flow circulations, and water quality indicators (TP, NH₃-N, COD_Mn) throughout the year. The results are as follows: (1) The hydrodynamic regime of Kuilei Lake is dominated by wind-driven currents, with seasonal flow circulations regulating pollutant migration and the suitability for submerged macrophyte growth; (2) Intense circulations in summer (July–September) enhance sediment resuspension and endogenous nutrient release, which are unfavorable for submerged plant colonization; (3) April–June is the optimal window for ecological restoration, with a mean flow velocity of 2.0–2.5 cm/s, TP ≤ 0.06 mg/L, NH₃-N ≤ 0.20 mg/L, COD_Mn ≤ 3.0 mg/L, and water temperature of 15–25 °C, providing favorable thresholds for submerged macrophyte recovery. This study reveals the coupled hydrodynamic–water environmental thresholds for shallow lake restoration, and offers a scientific basis for flow field regulation and ecological reconstruction of shallow lakes in the Yangtze River Delta. Full article

The surface disturbance caused by coal mining and the ecological restoration have changed the vegetation coverage and ecosystem functions of the Shengli mining area. This disturbance has affected the carbon and water cycles, resulting in complex response characteristics of water use effectiveness (WUE). To reveal these response characteristics, this paper uses multi-source remote sensing data from 2001 to 2024 and applies random forests to scale down MODIS 500 m net primary productivity (NPP) and MODIS 1 km evapotranspiration (ET) to 30 m resolution. Then, it calculates the WUE of the Shengli mining area to reveal the temporal and spatial variation patterns and characteristics of WUE in the mining area and the spoil dump. It also uses the Pearson correlation coefficient to analyze the driving factors of WUE. The results show that the determination coefficients R² of the NPP and ET scaling models are 0.961 and 0.7142 respectively. The WUE in the study area and four spoil dumps from 2001 to 2024 all follow the pattern of “decrease due to disturbance—recovery and rise—gradual stabilization”, with the peak WUE in the mining area reaching 1.123 g·C·m⁻²mm⁻¹ in 2002, a fluctuation decline from 2002 to 2011 with a valley value of 0.398 g·C·m⁻²mm⁻¹ in 2010, an annual increase trend from 2011 to 2013, and a basic stabilization from 2013 to 2024, with an average value of 1.001 g·C·m⁻²mm⁻¹ during this period. Compared to the average value of 1.061 g·C·m⁻²mm⁻¹ from 2001 to 2022, WUE has not yet returned to the initial level. The Pearson correlation coefficients ranked from high to low are: NDVI (0.59, +) > | deformation (−0.39, −) | > temperature (0.27, +) > rainfall (0.26, +) > mining area (0.072, +), indicating that NDVI and deformation are important factors affecting WUE. Further analysis of the relationship between NDVI disturbance and WUE reveals that the mean NDVI disturbance and recovery in the study area from 2001 to 2024 are 0.438 and 0.392 respectively. WUE shows a “first decline—then rise—then stabilization” phased evolution pattern during the “disturbance—recovery—stability” process of vegetation, and the disturbance intensity and recovery intensity are positively correlated with the rate of WUE decrease and increase. The combination analysis of deformation and WUE indicates that the deformation areas in the mining area and the inner spoil dump show a trend of WUE reduction due to the increase in deformation volume. The study shows that the continuous mining of open-pit coal mines continues to affect the water usage function of vegetation in the mining area. Subsequent restoration should prioritize strengthening surface stability, soil water retention, and vegetation reconstruction in the mining area, inner spoil dump, and areas with large deformation to improve the stability and water usage efficiency of ecological restoration. Full article

Coastal waters of eastern Guangdong are important fishing grounds and ecologically sensitive areas in the northern South China Sea, where nekton communities are increasingly affected by environmental heterogeneity and human activities. However, systematic studies on the spatial differentiation and driving mechanisms of nekton communities in this region remain insufficient. This study aimed to clarify the community structure, diversity distribution characteristics, and key driving environmental factors of nekton in the coastal waters of eastern Guangdong, and thereby provide scientific support for an ecological health assessment and sustainable utilization of fishery resources in this region. Based on bottom-trawl survey data from 19 stations in the coastal waters of eastern Guangdong, northern South China Sea, this study systematically analyzed the species composition, dominant species, and diversity distribution pattern of nekton and their correlations with environmental factors using methods including the Index of Relative Importance, Alpha diversity indices, Beta diversity indices, and redundancy analysis. A total of 119 nekton species belonging to three phyla, four classes, 14 orders, and 56 families were collected. Among them, there were 79 fish species (accounting for 66.39%), 36 crustacean species (30.25%), and four cephalopod species (3.36%). The dominant species were Trachypenaeus curvirostris and Portunus sanguinolentus (IRI ≥ 1000). Wilcoxon’s test showed that there were significant differences in the Shannon–Wiener index, Gini–Simpson index, and Pielou’s evenness between the nearshore and offshore groups, while no significant regional difference was observed in the richness index. Cluster analysis, based on the Bray–Curtis distance, divided the 19 stations into five clusters, with significant differentiation in species composition and functional structure within the nearshore group. RDA results indicated that environmental factors collectively explained 99.66% of the variation in community structure. Particulate Inorganic Carbon (PIC), Phosphate (PO₄³⁻), Distance to Port, Summer Maximum Chlorophyll-a (Chl-a), and Total Suspended Matter (TSM) were identified as the key driving factors. The coastal waters of eastern Guangdong boast rich nekton species, with significant differences in community structure between nearshore and offshore areas. The heterogeneity of the natural environment and human activity disturbances jointly shape the nekton diversity pattern in this region. The research results can provide a theoretical basis for regional marine ecological protection and fishery resource management. Full article

Three locally calibrated Indices of Biotic Integrity (IBIs) based on macroinvertebrates (B-IBI), zooplankton (Z-IBI), and phytoplankton (P-IBI) were developed to characterize relative aquatic ecological condition at impaired sites in Dongjiang Lake, a deep reservoir-type lake in China, during 2021–2023. Using synchronous monitoring data, candidate metrics for the three biotic groups were screened and assembled by integrating taxonomic diversity, community composition, pollution-tolerance attributes, trophic indicators, and functional feeding groups. Metric values were standardized using a linear transformation, and site conditions were classified using a unified five-class grading scheme under the present local calibration framework. A total of 327 taxonomic units (species or morphospecies) were recorded across the three biotic groups, indicating relatively high biodiversity in the study area. Under the present locally calibrated framework, most impaired sites were classified within the moderate-to-good range, with clear interannual variation and spatial heterogeneity. Upstream and downstream sections showed greater fluctuations in IBI classes than the lake area. The macroinvertebrate-based IBI was more sensitive to long-term and cumulative habitat disturbance, whereas the zooplankton- and phytoplankton-based IBIs responded more rapidly to short-term variation in nutrients and water quality. Together, these results indicate that multitaxon IBIs can provide complementary information on relative ecological condition within Dongjiang Lake and may support ecological zoning, pollutant management, and restoration prioritization in similar deep reservoir-type lake systems. Full article

Water scarcity is an increasingly pressing global concern, making the sustainable development of water resources a critical priority. Revered as the “Sacred Sea,” Lake Baikal holds the largest volume of freshwater in any single lake in the world, with exceptional water quality, conferring it with considerable global strategic importance. This study reviews the hydrological dynamics of Lake Baikal, including water level fluctuations and runoff patterns, and examines water resource utilization (including virtual water and long-distance diversion), along with its potential, challenges, and associated ecological risks, in an integrated manner. Previous studies reveal an interannual cycle of fluctuating water levels, with annual peaks typically occurring between September and October. Outflow runoff closely depends on lake water levels, while inflow runoff exhibits considerable variability. The Selenga River, the largest tributary originating from the Mongolian Plateau, significantly influences the lake’s hydrology and ecological integrity. Current water uses primarily include domestic supply, regional industry, and fisheries, while agricultural water use is relatively limited and mainly occurs within tributary catchments. Emerging options, such as virtual water trade, may offer relatively more manageable alternatives to large-scale transboundary water transfers in certain contexts. Given the multiple disturbances and potential impacts on the Lake Baikal ecosystem, this study advocates prioritizing ecological protection in water resource utilization and underscores the necessity of comprehensive, system-level assessments prior to any water extraction or diversion activities. Full article

Soil organic matter (SOM) dynamics in tropical montane ecosystems remain poorly understood, particularly regarding the relative importance of particulate versus mineral-associated fractions under varying disturbance regimes. This study investigated SOM fraction distribution across the Ericaceous and Afroalpine belts of Bale Mountains National Park, Ethiopia, an Andosol-dominated landscape subject to recurrent fire. Using a stratified sampling design (n = 30 plots) across four vegetation classes (Ericaceous belt, fragmented Ericaceous belt, herbaceous and heathland, and giant Lobelia areas), three fire history categories (<10, 10–25, and >25 years since fire), and three topographic positions (northern slopes, southern slopes, and central plateau), we quantified coarse particulate organic matter (cPOM: 149–2000 μm), fine particulate organic matter (fPOM: 53–149 μm), and mineral-associated organic matter (MAOM: <53 μm). Particulate fractions dominated the SOM pool, with cPOM and fPOM together accounting for >99% of measured organic carbon. Multivariate ordination revealed a primary gradient (PC1, 61.7%) contrasting particulate-dominated soils in less disturbed areas with relatively MAOM-enriched soils in fire-impacted and fragmented zones. A global comparison reveals a profound stability gap: the Bale Mountains utilize <2% of the mineral stabilization potential of comparable Andosols, demonstrating that extreme fire frequency (<25 yr return interval) overrides even the most reactive mineralogy. We critically evaluate whether standard size-based fractionation adequately captures mineral-associated carbon in volcanic soils and discuss methodological limitations. These results provide baseline data for conservation planning in this biodiversity hotspot and underscore the need for fire management strategies that balance ecological integrity with carbon storage objectives. Full article

Driven by global warming, increasing extreme precipitation events (EPEs) threaten low-lying coastal ecosystems. This study focused on the contemporary Yellow River Delta and established a continuous framework linking extreme precipitation, groundwater, and vegetation, based on long-term extreme precipitation changes during 1960–2022 and vegetation dynamics during 2001–2022. Using regional precipitation records, groundwater observations from 16 monitoring wells, and five-day kernel normalized difference vegetation index (kNDVI) data, we compared two EPEs that exceeded the 99th-percentile wet-day precipitation threshold and had complete precipitation–groundwater–vegetation observations. Our findings reveal that: (1) extreme precipitation was intensified in the study area, with an R99p trend of 19.1 mm/10 a; (2) vegetation disturbance was stronger and more persistent after the 2019 Lekima event, with a mean post-event kNDVI anomaly of −12.8%, whereas the 2022 Chaba event produced a weaker, later, and more spatially limited negative response; (3) groundwater response was also stronger in 2019, as the proportion of wells with above-surface water levels reached 43.8%, compared with 12.5% in 2022, indicating more extensive and longer-lasting inundation; (4) the shallowest post-event groundwater depth was significantly negatively correlated with kNDVI anomalies (r = 0.579, p < 0.001), and during the 2019 event, the kNDVI fell below about −17% when surface inundation lasted for 6 days. These results indicate that groundwater is a key hydrological link connecting extreme precipitation and vegetation response. This study provides new evidence for the identification and adaptive management of ecological risks in low-lying coastal deltas. Full article