Limnologica最新文献

{"title":"Microbial communities of desert river: Distinct roles of abundant and rare bacteria in the Tarim River ecosystem","authors":"Wenjuan Song ,&nbsp;Nana Xue ,&nbsp;Yuyi Yang ,&nbsp;Geoffrey Michael Gadd","doi":"10.1016/j.limno.2025.126294","DOIUrl":"10.1016/j.limno.2025.126294","url":null,"abstract":"<div><div>Desert inland rivers play crucial role in water resource supply and ecosystem maintenance. The composition and structure of microbial especially bacterial communities have important effects on water environment quality and ecological function. In this study, the composition, assembly mechanisms and co-occurrence network of bacterial communities were studied in Tarim River, the largest inland desert river in China. The research found significant differences in α-diversity and β-diversity between abundant and rare taxa across free-living and particle-associated bacteria. <em>Pseudomonadota</em> dominated bacterial communities, and the abundant taxa and rare taxa of both free-living and particle-associated showed a high variation of percentages. <em>Verrucomicrobiota</em> enriched in the abundant taxa of particle-associated bacteria. TOC, TN and NO₃-N had significant correlation with the composition of rare, total and abundant taxa of both free-living and particle-associated bacteria, while TP also had significant correlation with the composition of rare taxa of free-living bacteria. Total taxa in both free-living and particle-associated bacteria were more fitted by neutral model and influenced by stochastic processes, while the rare and abundant taxa were less influenced by stochastic processes. Furthermore, the co-occurrence network analysis revealed that rare taxa could serve as critical connectors and module hubs in free-living bacteria, compared to particle-associated bacteria. Overall, our study highlights the distinctive roles of abundant taxa and rare taxa in bacterial community assembly and ecosystem function in desert river ecosystems. Understanding these roles is essential for developing conservation strategies aimed at preserving microbial diversity and sustaining ecosystem services in vulnerable habitats.</div></div>","PeriodicalId":51110,"journal":{"name":"Limnologica","volume":"115 ","pages":"Article 126294"},"PeriodicalIF":2.0,"publicationDate":"2025-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145268984","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modeling diverse environmental responses of reservoirs to floating photovoltaic systems","authors":"Evan M. Bredeweg ,&nbsp;Ivan Arismendi ,&nbsp;Christina A. Murphy ,&nbsp;Sarah K. Henkel","doi":"10.1016/j.limno.2025.126293","DOIUrl":"10.1016/j.limno.2025.126293","url":null,"abstract":"<div><div>Floating photovoltaic (FPV) systems are emerging as a promising strategy for large-scale clean energy production worldwide. However, by altering key physical drivers such as solar radiation and wind mixing, FPV installations may have also unintended consequences for lakes and reservoirs. Given the wide diversity of freshwater systems globally, understanding the consistency in direction and magnitude of environmental responses to FPV deployment is critical for informed regulatory oversight and sustainable energy development. Here, we used process-based models to simulate the effects of FPV coverage on 11 reservoirs across the United States. This is the first multi-reservoir analysis using a laterally averaged 2D process-based modeling framework to systematically evaluate FPV impacts across diverse climatic and morphometric contexts, enabling direct comparison of magnitude and direction of responses among systems. Specifically, we evaluated changes in (1) surface and outflow temperature, (2) thermocline depth, (3) water column stability, (4) dissolved oxygen concentrations, and (5) potential suitable habitat availability for warm- and cold-water fishes. We quantified changes in these response variables by an iterative approach that simulates increases in FPV coverage and compares them with reference conditions. We summarized responses for winter (January–February) and summer (July–August). As expected, our simulations show that increasing FPV coverage consistently cooled surface waters and altered thermal stratification patterns, but the magnitude and environmental implications of these changes varied among reservoirs. Notably, greater FPV coverage led to increased variability in habitat suitability for aquatic species, with some reservoirs exhibiting distinct and sometimes divergent responses. These findings underscore the importance of considering local environmental contexts when assessing FPV impacts. While large-scale FPV systems offer potential benefits for climate mitigation, their ecological effects, particularly on thermally sensitive biota, require careful site-specific evaluation to avoid unintended consequences to local freshwater biodiversity.</div></div>","PeriodicalId":51110,"journal":{"name":"Limnologica","volume":"115 ","pages":"Article 126293"},"PeriodicalIF":2.0,"publicationDate":"2025-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145268489","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimizing phosphorus release risk index based on river sediment physicochemical properties","authors":"Wen Zhang ,&nbsp;Wenxi Pan ,&nbsp;Qin You ,&nbsp;Ningtao Wang","doi":"10.1016/j.limno.2025.126292","DOIUrl":"10.1016/j.limno.2025.126292","url":null,"abstract":"<div><div>This study develops a framework to optimize the selection of phosphorus release risk indices (PRRIs) for river sediments, based on key physicochemical properties—organic matter (OM), redox potential (Eh), and the CDB-P/Ca-P ratio (ROP). To address variability in PRRI applicability across sediment types, sediments from six rivers in China’s Sichuan Basin were analyzed. Results show that universal indices—including the Eutrophication Risk Index (ERI), Soil Phosphorus Storage Capacity (SPSC), Degree of Phosphorus Saturation (DPS), and Phosphorus Sorption Index (PSI)—exhibit strong, significant correlations with phosphorus release fluxes across all sediment categories (r = 0.71–0.89, <em>p</em> &lt; 0.01). Sediment classification further improves prediction accuracy: ERI and PSI perform best in OM-rich sediments (OM-1), where organic matter drives adsorption-desorption processes; Non-apatite inorganic P (NAIP) and Water-Soluble P (WSP) are reliable indicators in CDB-P-dominated systems (ROP-1); ERI is prioritized in weakly reducing sediments (Eh-2) (r = 0.90); and DPS, alongside Equilibrium P Concentration at net zero sorption (EPC₀), is more applicable in Ca-P-dominated sediments (ROP-2). This framework balances assessment accuracy and operational feasibility, offering actionable guidance for precise phosphorus release risk evaluation and targeted watershed management.</div></div>","PeriodicalId":51110,"journal":{"name":"Limnologica","volume":"115 ","pages":"Article 126292"},"PeriodicalIF":2.0,"publicationDate":"2025-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145119473","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A technique to monitor growth and spread of early-stage variable-leaf watermilfoil in a shallow impoundment","authors":"Noah Bohl ,&nbsp;Michael R. Twiss ,&nbsp;Diana T. White","doi":"10.1016/j.limno.2025.126291","DOIUrl":"10.1016/j.limno.2025.126291","url":null,"abstract":"<div><div>We describe an approach to measure the invasiveness of <em>Myriophyllum heterophyllum</em> (variable leaf watermilfoil) in a shallow dystrophic impoundment at the early stages of an invasion. Over an eight-week observation period, dry weight measurements show a biomass specific rate growth rate of 0.0048·day⁻¹, consistent with other studies of invasive watermilfoil growth, and a diffusion rate (biomass spread) of D = 9.2 cm²·d⁻¹, which describes the horizontal encroachment into plant-free sediment.</div></div>","PeriodicalId":51110,"journal":{"name":"Limnologica","volume":"115 ","pages":"Article 126291"},"PeriodicalIF":2.0,"publicationDate":"2025-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145097893","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The first eco-assessment of thirteen lakes in the Lake Van Basin of Türkiye with phytoplankton metrics as indicators of environmental conditions","authors":"Abuzer Çelekli","doi":"10.1016/j.limno.2025.126283","DOIUrl":"10.1016/j.limno.2025.126283","url":null,"abstract":"<div><div>Lakes are increasingly vulnerable to anthropogenic pressures such as pollution, eutrophication, and climate change, leading to biodiversity loss and ecosystem degradation. This study employed phytoplankton-based metrics across two hydrological periods to evaluate species-environment interactions and assess the ecological status of thirteen lakes in the Lake Van Basin. Canonical correspondence analysis (CCA) showed a strong correlation (96.7 %) between phytoplankton assemblages and environmental stressors. The most influential factors affecting phytoplankton distribution were conductivity, total organic carbon, total suspended solids, total phosphorus, total nitrogen, and nitrate. The CCA clearly distinguished the soda lakes, Lakes Erçek and Sodalı, which were characterized by high conductivity, alkaline pH, and high total organic carbon, and hosted assemblages dominated by taxa tolerant to organic pollution and salinity. In contrast, Lake Hıdırmenteş supported phytoplankton communities adapted to elevated nutrient and turbidity levels, while the Ahlat Marshes were associated with species indicative of nitrogen enrichment<em>.</em> The MPTI−modified phytoplankton trophic index proved to be an effective tool for ecological assessment, showing a strong correlation with total phosphorus (r = 0.925, p &lt; 0.01). The MPTI indicated that Lakes Nemrut, Aygır, and Nazik had a high ecological status, whereas Lakes Erçek, Hıdırmenteş, and Adırum showed a poor status and Lakes Turna and Hasantimur had a moderate one. This first eco-assessment of the region underscores the value of phytoplankton as sensitive indicators of environmental stress and supports the application of the MPTI for ecological status classification in saline and freshwater lakes of the Lake Van Basin.</div></div>","PeriodicalId":51110,"journal":{"name":"Limnologica","volume":"115 ","pages":"Article 126283"},"PeriodicalIF":2.0,"publicationDate":"2025-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145050224","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Interannual variability in dissolved organic matter (DOM) concentration and quality in shallow water bodies of Tierra del Fuego (Argentina)","authors":"Patricia E. Garcia ,&nbsp;Maria V. Castro ,&nbsp;María C. Maluendez Testoni ,&nbsp;Patricia Rodríguez","doi":"10.1016/j.limno.2025.126282","DOIUrl":"10.1016/j.limno.2025.126282","url":null,"abstract":"<div><div>Dissolved organic matter (DOM) is a crucial component of the global carbon cycle, significantly influencing aquatic ecosystems through its quantity and quality, which are shaped by abiotic factors such as precipitation, runoff, and solar radiation. Recently, the role of winter conditions, particularly ice cover, has gained attention due to the ongoing biogeochemical processes that occur during this period. This study explores the effect of winter precipitations on DOM dynamics in humic shallow lakes and beaver ponds in Tierra del Fuego over two consecutive years. Higher accumulated precipitation in 2021 compared to 2022 led to differences in DOM properties. While dissolved organic carbon (DOC) levels were higher in 2022, likely due to concentration effects from reduced precipitation, shallow lakes and beaver ponds exhibited distinct responses. Absorbance-based (water color, SUVA and spectral slope) assessments revealed a slight increase in DOM molecular size in shallow lakes during 2022, whereas fluorescence-based indices (HIX and BIX) indicated greater humification in 2021 but fewer humic components, suggesting complex patterns of allochthonous DOM mobilization. These findings highlight the importance of precipitation regimes and runoff in shaping DOM dynamics in subantarctic aquatic systems, with significant contribution from the surrounding soils and vegetation.</div></div>","PeriodicalId":51110,"journal":{"name":"Limnologica","volume":"115 ","pages":"Article 126282"},"PeriodicalIF":2.0,"publicationDate":"2025-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145027735","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ecological risk assessment of the impact of trace metal contamination on the benthic fauna and sediment of River Siluko, Edo State, Nigeria","authors":"N.K. Egun ,&nbsp;U.C. Olowo ,&nbsp;E. Erhurhu ,&nbsp;C.O. Enabulele ,&nbsp;I.P. Oboh","doi":"10.1016/j.limno.2025.126281","DOIUrl":"10.1016/j.limno.2025.126281","url":null,"abstract":"<div><div>This study evaluated the potential ecological and human health risk of trace metal pollution in sediment and benthic fauna (<em>Pila ampullacea</em>) of River Siluko. Result showed trace metal contamination of both sediment and <em>P. ampullacea</em>, with concentration profile of Fe &gt; Zn &gt; Cu &gt; Cr &gt; Mn &gt; Co &gt; Ni &gt; Pb in sediments, and Fe &gt; Zn &gt; Cu &gt; Mn &gt; Ni &gt; Co &gt; Cr &gt; Pb in <em>P. ampullacea</em>. Contamination factor values for Zn, Cu, Mn, Cr, Co, Ni and Pb were of low degree contamination (CF &lt; 1) and Fe was of very high degree of contamination (CF &gt; 6). The contamination degree (CD) values of the study Stations indicate a very high degree of sediment contamination from trace metals (CD ≥ 24). Potential ecological risk index (PERI) values classified the study stations 1, 2, 3 and 4 as of low ecological risk (PERI ≤ 150). Toxic Response Index Values (TRI) indicate no risk to aquatic organisms (TRI ≤ 5). Human health risk assessment associated with the consumption of contaminated <em>P. ampullacea</em> indicated non – carcinogenic risk (HI &gt; 1) and carcinogenic risks to consumers, as the integrated carcinogenic risk (ICR) value classified the consumption of the edible part of <em>P. ampullacea</em> as extremely high risk (Grade VII) to consumers. The need for exigent actions to be taken in the abatement and regulation of identified anthropogenic activities responsible for the release of these metals into River Siluko is recommended.</div></div>","PeriodicalId":51110,"journal":{"name":"Limnologica","volume":"114 ","pages":"Article 126281"},"PeriodicalIF":2.0,"publicationDate":"2025-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145010330","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Simultaneous monitoring of algal bloom and aquatic vegetation in eutrophic shallow lakes of the middle and lower yangtze river basin using deep learning","authors":"Jingming Wang ,&nbsp;Yu Cai ,&nbsp;Chang-Qing Ke ,&nbsp;Jianwan Ji ,&nbsp;Yao Xiao ,&nbsp;Genyu Wang ,&nbsp;Haili Li","doi":"10.1016/j.limno.2025.126280","DOIUrl":"10.1016/j.limno.2025.126280","url":null,"abstract":"<div><div>In recent years, lake ecosystems have faced severe challenges, including the increasingly severe problem of lake eutrophication and the rapid degradation of aquatic vegetation (AV). These issues pose significant threats to water quality, biodiversity, and human health. Traditional methods struggle to accurately and simultaneously monitor algal bloom (AB) and AV due to their similar spectral characteristics. Furthermore, existing studies have predominantly focused on large lakes, leaving small and medium-sized lakes understudied. This study addresses these gaps by employing the UNet+ + deep learning model to simultaneously map AB and AV in 44 eutrophic shallow lakes (area&gt;20 km²) in the middle and lower Yangtze River Basin (MLY). Utilizing Landsat remote sensing images from 2013 to 2023, the research provides a comprehensive analysis of the spatiotemporal dynamics of AB and AV. The results reveal significant spatiotemporal variations in AB and AV distribution. Additionally, the number of lakes experiencing algal bloom increased significantly (p &lt; 0.01), and the area of aquatic vegetation exhibited a significant decrease. Unlike previous studies that focused on single categories or large lakes, this research addresses the complexity of \"grass-algae coexistence\" and provides a comprehensive understanding of their spatiotemporal dynamics. This research not only advances the application of deep learning in aquatic ecosystem monitoring, but also provides valuable insights for lake management and ecological restoration in the MLY region.</div></div>","PeriodicalId":51110,"journal":{"name":"Limnologica","volume":"114 ","pages":"Article 126280"},"PeriodicalIF":2.0,"publicationDate":"2025-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144913482","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reed between the lines: Terrestrial 3D laser scanning to assess recreational impacts on lakeshore vegetation","authors":"Nora Meyer ,&nbsp;Matthias Kunz ,&nbsp;Roman Mathias Link ,&nbsp;Goddert von Oheimb","doi":"10.1016/j.limno.2025.126279","DOIUrl":"10.1016/j.limno.2025.126279","url":null,"abstract":"<div><div>Swimming in lakes and spending time on the shore are popular summer activities, but as climate change continues and land use intensifies, pressure on lakeshore ecosystems is increasing. In particular, plants play an important role in these ecosystems by stabilizing the shoreline and providing habitat, but they suffer from trampling and destruction caused by human use. However, the effects of lakeshore recreation on plants are not well understood. To assess the impact of bathers on the reed bed and the area of the shoreline used for sunbathing, terrestrial laser scanning (TLS) was employed to analyze changes in the aboveground spatial distribution of plant material at very high spatial or temporal resolution. Measurements were taken before and after summer weekends at nine lakes in Brandenburg, Germany, and the occupancy status of voxels (i.e., cubic volume elements) in voxelized TLS point clouds of the lakeshore vegetation was compared. In addition, standardized visitor counts were conducted to determine the bathing sites' visitation rates. Over the course of a summer weekend, bathing and control sites displayed similar changes in total reed volume. The analysis has identified no clear relationship between the highly dynamic volume changes and the bathing activity along the gradient of visitor density that has been considered here. The variation of vegetation in the sunbathing area was generally small and showed no clear tendency for directed loss or gain after a weekend. As we studied established sites, the vegetation may have already adapted to human use. While the current visitor density and visitor behavior do not appear to be causing discernible changes, visitor management measures will be necessary if the intensity of use increases in the future.</div></div>","PeriodicalId":51110,"journal":{"name":"Limnologica","volume":"114 ","pages":"Article 126279"},"PeriodicalIF":2.0,"publicationDate":"2025-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144902326","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Organic nitrogen fuels phytoflagellate expansion in browning lakes: Evidence from paleolimnological records","authors":"Camilla Hedlund Corneliussen Hagman ,&nbsp;Gunnhild Riise,&nbsp;Thomas Rohrlack","doi":"10.1016/j.limno.2025.126278","DOIUrl":"10.1016/j.limno.2025.126278","url":null,"abstract":"<div><div>The increasing influx of terrestrially derived dissolved organic matter (DOM) into lakes, commonly referred to as browning, is a widespread phenomenon with significant ecological and societal consequences. Browning is frequently associated with the proliferation of mixotrophic phytoflagellates (PFs), yet the underlying mechanisms remain debated. In this paleolimnological study, sediment cores from seven lakes in southeastern Norway were analyzed to assess the role of potential drivers of PF success. The study focused on two ecologically distinct PFs, <em>Gonyostomum semen</em> and cryptophytes, using pigment biomarkers to reconstruct their historical abundance alongside proxies for DOM, nutrients, and climate. Piecewise regression analysis revealed increases in both PFs with a relatively high degree of synchrony. Generalized additive models identified nitrogen as the most consistent predictor of PF-specific pigments, while DOM was the primary predictor of nitrogen concentrations. These findings support the hypothesis that browning promotes PF expansion primarily by increasing the input of organic nitrogen that enters lakes as a component of DOM. Other proposed mechanisms, such as enhanced stratification, reduced transparency, or iron enrichment, were not consistently supported across lakes. The temporal patterns of browning and increasing PF success suggest a strong influence from historical land-use changes, particularly afforestation and wetland drainage. Results of the present study highlight the importance of land-use legacies in shaping phytoplankton community structure and provide new insights into the ecological consequences of ongoing DOM enrichment in inland waters.</div></div>","PeriodicalId":51110,"journal":{"name":"Limnologica","volume":"114 ","pages":"Article 126278"},"PeriodicalIF":2.0,"publicationDate":"2025-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144879037","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}