Search Results (14,799)

Alpine wetlands in the Qinghai Lake Basin, located on the northeastern Qinghai–Tibetan Plateau, are ecologically important but highly vulnerable to climate change and anthropogenic disturbance. Traditional field-based surveys are labor-intensive and spatially constrained, underscoring the need for automated remote sensing approaches for large-scale wetland mapping. In this study, an object-based image analysis (OBIA) framework was developed by integrating Sentinel-2 optical imagery with Sentinel-1 synthetic aperture radar (SAR) data to classify two representative plateau wetland types: marsh meadows and inland tidal flats. Seven categories of features were evaluated, including spectral features, vegetation indices, water indices, red-edge features, topographic variables, radar backscatter, and geometric-textural metrics. The Separability and Thresholds (SEaTH) algorithm was employed for feature selection and optimization prior to classification using a Random Forest model. The results indicate that the incorporating geometric and textural features significantly improved classification performance, achieving an overall accuracy (OA) of 82.53% and a Kappa coefficient of 0.74. Moreover, the SEaTH-based feature optimization scheme yielded the best performance, with an OA of 86.24% and a Kappa coefficient of 0.79. Compared with the full feature set, this approach improved producer’s accuracy by 3.96–6.11% and increased overall accuracy by 1.48%. The proposed framework provides an effective and computationally efficient approach for mapping ecologically fragile alpine wetlands and offers valuable support for wetland conservation in the Qinghai Lake Basin. Full article

In this article, I will use the ecological approach to explore the recent videos of Pinar Öğrenci. I will focus on two works: Agit (2022) and Cemetery of the Nameless (2025). In the latter work, there is a complex examination of the interplay between the precarious paths taken by refugees and the climate change crisis. She also explores the multiple layers of history and memorialization in sites that have been scarred by genocide. In Cemetery of the Nameless (2025), Pinar establishes an analogy between missing bodies and the contamination of the water of Lake Van. However, this connection is not linear and there is no direct cause and effect; Lake Van was meant to be a transit zone for the refugees, not a cemetery. I will argue that the function of analogy is in its suggestion of comparisons, rather than the establishment of equivalence. Öğrenci thereby puts the analogy to work in a dual manner—it both amplifies and concentrates our attention. We listen to the narratives of migration while looking at the scenes caused by climate change. The image broadens the horizon of the narrative, and the voice sucks the gaze into a dark hole. In this manner, Öğrenci’s art of witnessing, which both combines and separates voice and image, amplifies and concentrates the transfer of information. I will also frame this commentary on the artworks with a broader discussion on the politics of care and memorialization. Full article

High Andean lagoons in southern Peru have critical hydrological and ecological functions; however, long-term time series integrating trophic, integral quality, and metal contamination metrics to support adaptive management are lacking. A total of 1846 records (2015–2024) from four systems (3100–4600 m a.s.l.) were analyzed using seven indices assessing trophic status (TSItsr, TRIX), general water quality (OWQI, WQIHA, CCME-WQI), and metal contamination (HPI, CD). Temporal trends were assessed using Mann–Kendall and Theil–Sen slope; spatial heterogeneity using Kruskal–Wallis and Dunn–Bonferroni comparisons; controlling factors using distance-based redundancy analysis (999 permutations); and functional typology using Ward’s hierarchical clustering on Z-standardized data. 93% of the series lacked monotonic trends (52/56 lagoon–stratum × index combinations), demonstrating high interannual stability; spatial variance was marked (ε² = 0.73 in CCME-WQI). Distance-based redundancy analysis (db-RDA) explained 24.6% of total variability, with lake identity as the dominant driver (~45%), followed by temporal change (~8%). Four functional archetypes emerged, including a metal-eutrophic hotspot (HPI ≈ 213; CD ≈ 19) and recovering reservoirs with intermediate water quality indicators. Joint thresholds (TSItsr ≥ 60 + HPI ≥ 100) establish early-warning criteria, with Paucarani (HPI = 213) approaching the critical domain where metal-driven stress may facilitate cyanobacterial dominance. Systems show temporal resilience but strong spatial divergence induced by local pressures. The proposed typology and thresholds provide an operational basis for early warnings and prioritization of remediation actions in high-mountain ecosystems subject to increasing anthropogenic stress. Full article

In this study, a gradientstructured (GS) AZ31 Mg alloy sheet with high stretch formability is fabricated using turned bearing extrusion (TBE). The mechanism by which the gradient structure contributes to the improvement in formability is elucidated. The Erichsen index of the GS sheet reaches 5.51 mm, representing an increase of up to 89.3% compared to conventional extruded (CE) sheets. During the Erichsen cupping test, when the coarsegrained (CG) layer of the GS sheet is positioned on the inner side, the large grains promote the activation of deformation twins, thereby effectively enhancing the strain accommodation capacity in the thickness direction. Meanwhile, the finegrained (FG) outer layer effectively suppresses the formation of {10$\stackrel{-}{1}$1} and {10$\stackrel{-}{1}$1}-{10$\stackrel{-}{1}$2} twins, reducing local strain concentration. Full article

Urban lake scenic areas serve as crucial ecological barriers but face acute conflicts between expansion and conservation. Existing research has often overlooked microscale landscape fragmentation and its associated ecological effects. Focusing on the Wuhan East Lake ecotourism scenic area (Wuhan East Lake), this study investigated the spatiotemporal impacts of micro-scale land-use transitions on ecosystem service value (ESV). To evaluate the historical evolution of ESV from 2010 to 2024, an improved equivalent factor method was coupled with a patch-generating land-use simulation (PLUS) model. Spatial autocorrelation and landscape pattern metrics were then incorporated to diagnose structural degradation and establish a foundation for simulating the four development scenarios for 2035. Results demonstrate that sporadic construction expansion led to a decline in total ESV from 2.445 to 2.216 billion CNY, driving a pronounced “core-hot vs. edge-cold” spatial disparity. Among future projections, the Sustainable Development pathway emerges as optimal, effectively balancing economic demands with the need to minimize ecological fragmentation. Ultimately, this study contributes to the literature by integrating microscale landscape fragmentation analysis with a PLUS-based multi-scenario simulation to provide a refined understanding of ecosystem service dynamics in urban lake systems, thereby offering a scientific reference for resilient spatial planning and policymaking. Full article

Glioblastoma (GBM) is the most lethal and aggressive primary brain tumor in adults. Despite a standard-of-care regimen involving surgical resection, radiotherapy and temozolomide (TMZ), median overall survival typically hovers between 12 and 15 months. This poor prognosis is driven by profound intratumoral heterogeneity, glioma stem cell populations, and an immunosuppressive microenvironment that collectively fuel resistance to traditional apoptosis-centric therapies. Ferroptosis—a form of regulated cell death driven by iron-dependent phospholipid peroxidation and the collapse of antioxidant defenses—has emerged as a compelling alternative for eliminating therapy-refractory GBM cells. This review examines the molecular machinery of ferroptosis in glioma and explores how an additional regulatory layer, noncoding RNAs (ncRNAs), modulates this process. We highlight key experimentally validated axes where microRNAs, long noncoding RNAs (lncRNAs), and circular RNAs (circRNAs) orchestrate iron handling and antioxidant thresholds. These include sensitizers like miR-147a and circLRFN5, which promote iron overload, and resistors like circCDK14 and TMEM161B-AS1, which act as “ferroptosis brakes”. Furthermore, we discuss how integrative analyses of TCGA and CGGA cohorts have yielded ferroptosis-related lncRNA signatures that robustly predict patient survival. Finally, we outline the clinical potential of these ncRNAs as biomarkers and therapeutic targets while addressing the delivery challenges, such as the blood–brain barrier, that must be overcome to achieve precision, ferroptosis-oriented GBM therapy. Full article

Background: An aortic disease diagnosis can be perceived by patients as a stressful and often life-altering event. In addition, an acute event, such as aortic rupture or dissection—and the surgical intervention that will be required to address it—can be viewed as potentially life-threatening and traumatic. Serious health conditions, including stroke and acute coronary syndromes, have been described in the literature to correlate with trauma-like symptoms. Post-traumatic stress disorder (PTSD) is well described in connection with external traumatic events, such as war, assault and similarly catastrophic events. A key element of this type of PTSD is that its occurrence arises secondary to an external traumatizer. However, recent work has suggested that internal events—such as a catastrophic medical event (e.g., acute cardiovascular event and/or surgery)—can trigger PTSD symptoms. An important question is whether medical event-initiated PTSD can (or should) be treated similarly to traditionally defined PTSD, when the triggering threat may persist rather than having been confined to a past event. This systematic review will summarize the literature on the occurrence of PTSD as a consequence of an acute cardiovascular event and attempt to identify effective treatments using meta-analysis, if the literature quantity and quality support it. Methods: The search strategy will include publicly available electronic databases, including MEDLINE via PubMed and OVID, EMBASE via Elsevier, Cumulative Index for Nursing and Allied Health Literature (CINAHL) via EBSCOhost, SCOPUS, PsychInfo, and the Cochrane Library, to identify publications that report the development and/or treatment of PTSD as a consequence of an acute cardiovascular event, which include cardiac arrest, acute coronary syndromes, and acute aortic syndromes. Identification of publications, article classification, methodological review/quality assessment, and data extraction will be performed by two trained experts in cardiovascular epidemiology, with the resolution of disagreements carried out by a third independent reviewer. The review conduct and meta-analysis will follow PRISMA and MOOSE guidelines. Data will be aggregated using random effects models when quantitative data are reliable and heterogeneity is reasonable. If a quantitative synthesis is not possible due to data quality, a narrative synthesis will be conducted. Statistical heterogeneity will be assessed by I² statistics. The quality of evidence will be assessed using the GRADE criteria. Ethics and Dissemination: This study did not require an institutional review board or human subjects protection committee approval given the nature of the study design. The results will be published in a peer-reviewed journal, along with recommendations for future research. Full article

The hydrogeochemical characterization of shallow volcanic lakes at the Sete Cidades Volcano (São Miguel, Azores) provides new insights into the processes controlling water chemistry in low-depth lacustrine systems within active volcanic environments. Fourteen lakes (0.6–4 m deep) were sampled during two campaigns (winter 2024 and spring/summer 2025), combining in situ physicochemical measurements and major ion analyses along vertical profiles. The lakes are holomictic, cold (11.3–17.6 °C), slightly acidic (pH 5.66–5.95), and weakly mineralized (EC ~65–69 µS/cm), indicating dilute waters of predominantly meteoric origin. Hydrochemical facies are dominated by Na–Cl type, with strong correlations between chloride and conductivity (r = 0.857), supporting a major contribution from marine atmospheric deposition. To move beyond correlation-based interpretation, Gibbs diagrams and saturation indices (PHREEQC) were applied to constrain the dominant geochemical processes. Most samples plot within the precipitation dominance field, while all calculated saturation indices are negative (SI < 0), indicating undersaturation with respect to carbonate, evaporite, and silicate minerals. These results demonstrate that water chemistry is primarily controlled by atmospheric inputs, with only minor contributions from water–rock interaction and negligible influence of evaporation or mineral equilibrium processes. Seasonal increases in HCO₃⁻ and dissolved CO₂ at depth suggest enhanced organic matter decomposition during warmer periods, highlighting the role of biogeochemical processes in modulating carbon dynamics in shallow systems. The absence of a clear hydrothermal signature further distinguishes these lakes from deeper volcanic systems in the Azores. This study provides the first integrated hydrogeochemical framework for shallow volcanic lakes in the region, combining classical hydrochemistry with process-based tools. The results establish a quantitative baseline for assessing environmental change and improve the interpretation of external (atmospheric) versus internal (geochemical and biological) controls in volcanic lake systems. Full article

This study examines the potential benefits of incorporating a lending-value criterion into the design of portfolios with long-term objectives. Because such portfolios often include significant positions in illiquid assets—typically difficult to sell under stressful market conditions—it has been argued that they should be designed with this constraint in mind. The underlying idea is that portfolios with adequate borrowing capacity may be better able to withstand adverse market conditions and thus avoid the losses incurred when managers are forced to sell assets under duress. Using returns data over a twenty-year period, which included two major financial crises, the study finds that the potential benefits of this approach are minimal. In other words, adding a lending-value constraint to the optimization problem is largely irrelevant, since in most cases the constraint is not binding. Put differently, the asset weights selected under the standard optimization framework already yield portfolios with an adequate lending value. Full article

Sustainable development of regional water resources requires objective classification of lake systems according to dominant hydrochemical processes. The aim of the study was to develop a data-driven hydrochemical typology of natural lakes in Polissya based on the Self-Organizing Map (SOM) method to identify functionally distinct water quality regimes and justify management decisions within the basin approach. The study covered nine lakes of different genesis and trophic status. Key water quality indicators were analyzed: total nitrogen (TN), biochemical and chemical oxygen demand (BOD₅, COD), suspended solids (TSS), iron (Fe), and total dissolved solids (TDS). Descriptive statistics, correlation analysis, and neural network SOM modeling with subsequent clustering were applied. The results revealed strong positive correlations between TN, BOD₅, COD, and TSS, indicating joint control by biogenic and organic processes, while TDS showed negative correlations with organic indicators, reflecting mineralization control. SOM classification allowed us to identify three hydrochemical clusters: background systems with low anthropogenic load; organically enriched lakes with intense biogeochemical cycling; and mineralization-controlled water bodies dominated by geogenic factors. It has been established that spatial features of land use and morphometric characteristics (depth, type of feeding, hydrological connectivity) determine the sensitivity of lakes to external loads and their location. Full article

Accurate spatial identification of check dams is a key prerequisite for evaluating soil and water conservation benefits and optimizing dam system planning on the Loess Plateau. Current deep learning models face severe misclassification and omission issues under complex terrain due to the scarcity of check dam samples and the lack of prior geographic knowledge. This study proposes a recognition method based on Faster R-CNN, constrained by suitable areas and microtopography. The Xiliugou watershed in Inner Mongolia was selected as the study area. Based on Google Earth imagery and field survey data, a check dam sample dataset was constructed, integrating the morphological features of “linear dam body with a trapezoidal slope.” Using the construction suitable area constraints defined by the Technical Specifications for Check Dams and microtopography standard deviation (δ) derived from DEM as dual spatial filtering mechanisms, these were deeply embedded into the Faster R-CNN model to limit the search space and enhance geographic plausibility. Experimental results show that the constrained Faster R-CNN model achieved a precision and recall of 92.86% and 96.89%, compared with the accuracy rate of only deep learning model recognition (60.61%), which significantly increased by 32.25%, indicating that geographical constraints have an enhancing effect. Using this method, a total of 191 embankment dams were identified in the Xiliugou Basin. New 30 unrecorded embankment dams (21 small dams and 9 micro-dams) were discovered. The model’s good generalization ability was verified in the Han Tiechuan geographical isolation area, which contained 153 embankment dam samples, with an accuracy rate of 72.94%. Spatial analysis further revealed the “successive interception along tributaries” distribution pattern and strong spatial aggregation characteristics (box dimension D ≈ 0.36) of check dams in the Xiliugou watershed. This study confirms the critical role of suitable area and microtopography constraints in improving the accuracy and reliability of deep learning models and provides a transferable technical paradigm for automated, high-precision surveys of regional soil and water conservation projects. Full article

Hydrological fluctuations drive community dynamics in floodplain lakes, yet their integration into water resource management remains limited. Here, we integrated environmental DNA (eDNA) metabarcoding with hydroacoustic surveys to investigate vertebrate community assembly in China’s largest freshwater lake (Poyang Lake) during the winter dry season. We detected 65 vertebrate species, with Cypriniformes dominating. Beta-diversity partitioning revealed that turnover dominated taxonomic and functional dissimilarity, while phylogenetic beta diversity was characterized by nestedness, which is consistent with environmental filtering. Functional richness declined with water depth, coinciding with hydroacoustic vertical size stratification, indicating niche partitioning along depth gradients. Null model analysis showed stochastic processes (ecological drift) dominated regional assembly (72.97%), whereas joint species distribution modeling attributed explained variation to environmental factors (28.9%, notably water depth) and species associations (29.7%) at local scales. This hierarchical framework, regional stochasticity shaping the species pool and local deterministic filtering structuring communities, reframes environmental flow conceptualization: effective management must preserve the full spectrum of hydrological variability and maintain bathymetrically diverse habitats that support functional niche differentiation. The integrated eDNA-hydroacoustic approach offers a non-invasive, high-resolution toolkit for biological assessment within regulatory water quality frameworks. Full article

Shoreline change detection from remote sensing imagery remains challenging in environments subject to water level fluctuations, as remotely sensed shoreline positions reflect instantaneous hydrodynamic states rather than true geomorphic change. In the Great Lakes, seasonal and short-term water level variations can produce apparent shoreline shifts unrelated to sediment dynamics. Reliable calibration with bathymetry and water level data can mitigate this effect, but such data are often unavailable or difficult to obtain for many coastal and lacustrine systems worldwide. To address this limitation, we proposed a morphology-based framework that quantifies geometric change between successive shoreline curves using a discrete Fréchet distance, a modified Euclidean distance and a Union distance metric. Rather than relying solely on cross-shore displacements, the approach leverages shape similarity to differentiate water-level-driven shifts from true morphological change. We evaluated the framework across three spatial scales (100 m, 500 m, and 1000 m) along 125 km of southwestern Lake Michigan coastline using 2010 and 2020 aerial imagery, benchmarking against water-level-calibrated DSAS erosion hotspots. The Fréchet distance improved monotonically with scale, achieving strong agreement at 1000 m (F1 = 0.84, Spearman $\rho$ = 0.79) but limited reliability at 100 m. While individual morphology-based metrics appeared competitive with or inferior to uncalibrated DSAS at each scale, the union of both distances substantially outperformed uncalibrated DSAS at management-relevant scales (F1 of 0.64 vs. 0.50 at 500 m and 0.79 vs. 0.42 at 1000 m), reflecting the complementary nature of shape-based and displacement-based detection. The Patient Rule Induction Method (PRIM) further identified gentle nearshore slopes and moderate separation from engineered structures as the geomorphic conditions under which the morphology-based and calibrated erosion indicators converged most closely (in-box F1 = 0.92 at 1000 m and 0.72 at 500 m). These results suggest that the proposed framework, particularly the complementary union of both metrics, provides a practical, calibration-free alternative for multiscale shoreline change screening in lacustrine and microtidal, data-limited environments, while local-scale applications still benefit from explicit water-level correction. Full article

Bodanella lauterborni W.M. Zimmermann and Heribaudiella fluviatilis (Areschoug) Svedelius are members of brown algae (Phaeophyceae) that exclusively inhabit freshwater habitats. Heribaudiella fluviatilis is the most frequently reported freshwater brown alga, widely distributed in the Northern Hemisphere. In contrast, B. lauterborni, one of the rarest algae globally, has been reported in only four glacial Alpine lakes and has not been observed in nature for nearly 50 years. Since 2019, the species has been considered locally extinct at its type locality, and its presence in the other three lakes is also questionable. Here, we report the occurrence of B. lauterborni in three springs on the Vlasina Plateau (Southeast Serbia), being the first finding of the species in Southeast Europe and the fifth discovery globally in environmental conditions not previously described for the species. We also provide detailed data on the morphology, ecology, and biogeography of B. lauterborni and H. fluviatilis. Additionally, we report the non-obligate association Hildenbrandio rivularis-Heribaudielletum fluviatilis discovered in two rivers. Our findings significantly expand the known ecological and geographical range of phaeophytes, highlighting Southeast Europe as a refugium for freshwater Phaeophyceae biodiversity. Full article

Soil moisture (SM) is a pivotal state variable of the terrestrial hydrosphere, modulating energy partitioning, agricultural productivity and extreme-event propagation. This study analyzes 43 years (1982–2024) of data to assess soil moisture (SM) dynamics in the Yellow River Basin (YRB). Results indicate a statistically significant basin-wide SM decline across weekly, monthly, and annual scales, with grid-scale slopes ranging from −2.26 × 10⁻⁴ to 8.32 × 10⁻⁵ m³ m⁻³ month⁻¹. Spatially, non-farm areas retain higher SM than cultivated lands, with a distinct upstream-to-downstream variability pattern. While alpine headwaters show moistening, pervasive drying characterizes mid- and lower-catchments. Critically, transitional landscapes are approaching tipping points, risking shifts into persistently wetter or drier stable states where minor perturbations could lock ecosystems into new conditions. This underscores the urgent need for targeted climate-adaptation interventions. Generalized additive modeling identifies surface net solar radiation, soil temperature, and vapor pressure deficit as dominant drivers across multiple temporal scales. Their respective contributions, averaged across the basin, accounted for 29.4%, 25.3%, and 23.0% of the explained variance. Additionally, actual evapotranspiration emerged as a significant driver on the weekly scale, particularly within the center of the basin. These findings enhance process-based understanding of SM variability and provide a scientific foundation for adaptive water-resource management in the YRB. Full article