Aquatic Sciences最新文献

{"title":"Seasonal response of benthic macroinvertebrate to environmental stressors in mountain streams: Trait convergence and functional homogenization","authors":"Mingyang Li,&nbsp;Lunhui Lu,&nbsp;Wenyu Xiao,&nbsp;Wenjuan Ouyang,&nbsp;Yuanyuan Zhang,&nbsp;Yifan Ding,&nbsp;Ning Jia,&nbsp;Xiangxiang Xie,&nbsp;Xi Zou,&nbsp;Peiming Ma,&nbsp;Yanbo Ma,&nbsp;Zhe Li","doi":"10.1007/s00027-026-01290-7","DOIUrl":"10.1007/s00027-026-01290-7","url":null,"abstract":"<div><p>Intensified human activities degrade hydrological conditions in mountain river ecosystems, directly impacting macroinvertebrate communities, yet responses via functional traits remain poorly understood. This study investigated environmental filtering and selection processes on benthic macroinvertebrate functional traits across wet and dry seasons in typical mountain streams, with specific emphasis on trait response thresholds. Analyses of 167 macroinvertebrate taxa revealed the consistent dominance of <i>r</i>-selected life-history strategies across seasons. Notably, this dominance was distinctly amplified during the wet season, as intensified hydrological parameters promoted the proliferation of <i>r</i>-selected traits, while elevated eutrophication indicators concurrently suppressed <i>K</i>-strategists. Trait responses diverged starkly between seasons. Patterns conformed to theoretical bell-shaped distributions during the dry season. However, intensified environmental stress resulted in significant declines in both trait responses and functional diversity during the wet season. Further threshold analysis successfully identified robust bioindicators, and clinging behavior served as a definitive indicator of low-flow conditions, while streamlined morphology and tegument respiration exhibited strong associations with low ammonia nitrogen concentrations. Critically, this study demonstrates that increasing environmental stressors drive a fundamental shift in benthic macroinvertebrate functional trait composition toward high-resistance traits. This shift promotes significant trait convergence and functional homogenization, posing a clear threat to ecosystem functions. The evidence presented by this study provides a baseline for predicting impacts of environmental change on community functions and offers critical insights for ecological management in mountain streams.</p></div>","PeriodicalId":55489,"journal":{"name":"Aquatic Sciences","volume":"88 2","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147560449","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Methane exchange across the sediment–water interface in a densely urbanized tropical Bay of Jakarta, Indonesia","authors":"Irfan Kampono,&nbsp;Nining Sari Ningsih,&nbsp;Fadjar Hidayat,&nbsp;Yaya Ihya Ulumuddin,&nbsp;Aditya R. Kartadikaria","doi":"10.1007/s00027-026-01285-4","DOIUrl":"10.1007/s00027-026-01285-4","url":null,"abstract":"<div><p>Jakarta Bay, a highly urbanized tropical estuary, exhibits methane (<span>({text{CH}}_{4})</span>) dynamics shaped by the interplay of terrestrial organic inputs, sediment redox stratification, and local hydrographic factors such as water depth, oxygen levels, and circulation. This study presents one of the first vertical assessments of sedimentary <span>({text{CH}}_{4})</span> distribution (0–100 cm below the seafloor) using a modified headspace technique and nondispersive infrared gas analysis. Field measurements conducted during two seasonal hydrographic conditions, the dry season (August 2023) and wet season transition (October 2023), revealed pronounced spatial and vertical variability in <span>({text{CH}}_{4})</span> accumulation. Nearshore and eastern stations showed elevated organic matter (OM) and bottom-water hypoxia and supported shallow sulfate–methane transition zones (SMTZs) at 30–40 cm depth and <span>({text{CH}}_{4})</span> concentrations reaching up to 1.2 µmol L⁻¹. Conversely, offshore western stations exhibited deeper sulfate penetration (&gt; 100 cm) and minimal <span>({text{CH}}_{4})</span> buildup (&lt; 0.3 µmol L⁻¹), reflecting more oxic and ventilated sediments. <span>({text{CH}}_{4})</span> flux across the sediment–water interface calculated using Fick’s first law ranged from slightly negative to positive but remained low in magnitude. These bidirectional fluxes suggest subtle gradients and localized redox control, with some stations exhibiting net <span>({text{CH}}_{4})</span> oxidation due to anaerobic oxidation of methane (AOM). Findings align with patterns in other eutrophic systems such as Chesapeake Bay and Bohai Sea, where eutrophication-driven stratification modulates methane cycling. The study underscores the need to integrate vertical profiling in methane research and highlights the importance of combining microbial analysis, OM characterization, and direct atmospheric flux measurements to refine emission estimates.</p></div>","PeriodicalId":55489,"journal":{"name":"Aquatic Sciences","volume":"88 2","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147559971","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Drivers of aquatic zoosporic parasites in natural and artificial environments","authors":"Maya Stoyneva-Gärtner,&nbsp;Hans-Peter Grossart,&nbsp;Thijs Frenken,&nbsp;Dirk S. Schmeller,&nbsp;Laura Garzoli,&nbsp;Serena Rasconi,&nbsp;Elżbieta Wilk-Woźniak,&nbsp;Albert Reñé,&nbsp;Slawek Cerbin,&nbsp;Cécile Lepère,&nbsp;Caio César Pires de Paula,&nbsp;Adeline Loyau,&nbsp;Aleksandra Kudeń,&nbsp;Ana Gavrilović,&nbsp;Christian Lønborg,&nbsp;Edward Walusiak,&nbsp;Ifigenia Kagalou,&nbsp;Ivana Trbojevic,&nbsp;Jurica Jug-Dujaković,&nbsp;Kristian Ivanov,&nbsp;Lisa Morales,&nbsp;Mahmut Sinan Erez,&nbsp;Maija Balode,&nbsp;Maja Berden Zrimec,&nbsp;Martyna Budziak,&nbsp;Miloš Stupar,&nbsp;Miroslav Androv,&nbsp;Petr Znachor,&nbsp;Pietro Marchese,&nbsp;Selene Chinaglia,&nbsp;Slobodan Zlatković,&nbsp;Télesphore Sime-Ngando,&nbsp;Qëndrim Ramshaj,&nbsp;Wojciech Krztoń,&nbsp;Blagoy Uzunov","doi":"10.1007/s00027-026-01287-2","DOIUrl":"10.1007/s00027-026-01287-2","url":null,"abstract":"<div><p>This review, based on more than 500 scientific studies published between 1880 and 2025, summarises current knowledge on the complex relationships between aquatic zoosporic parasites (AZP) and their hosts, the physical and chemical properties of the environment and the many surrounding organisms, to outline the key drivers of AZP diversity, abundance and infection success. It emphasises the urgent need to focus research on the influence of global climate and undesirable anthropogenically driven changes, such as eutrophication, pollution and biological invasions. Knowledge gaps are identified, along with research needs to decipher the diverse responses of AZP to ongoing changes in abiotic and biotic drivers. We believe that the summarised data and highlighted open research questions will benefit future research and help to better conserve natural biodiversity and manage artificial aquatic systems.</p></div>","PeriodicalId":55489,"journal":{"name":"Aquatic Sciences","volume":"88 2","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00027-026-01287-2.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147559798","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multi-scale land use effects on stream health in the Walawe Basin: integrating habitat, water quality, and biological indicators","authors":"Heshani Perera,&nbsp;Chandramali Jayawardana,&nbsp;Rohana Chandrajith","doi":"10.1007/s00027-026-01279-2","DOIUrl":"10.1007/s00027-026-01279-2","url":null,"abstract":"<div><p>Understanding the relationships between spatial scales of catchment land use and indicators of stream ecosystem health is crucial for the management of tropical river basins that are undergoing rapid environmental changes. This study was designed to assess stream health in Sri Lanka’s Walawe River Basin by integrating the changes in water quality, stream habitat quality, and macroinvertebrate-based indicators in response to different types of catchment land cover at multiple spatial scales. Twenty-nine sites (12 in the River Walawe and 17 in its tributaries) were sampled to evaluate the spatial and seasonal variations of water quality, habitat quality, and macroinvertebrate-based indicators. Seventeen tributaries (sub-catchments) were specifically selected to investigate the effects of types of land cover on stream health. Bivariate regression analysis and canonical correspondence analysis were conducted to evaluate the impact of spatial scales of land cover in the catchment on stream health. The regression analysis revealed that forest cover within the 200-m and 500-m stream buffers strongly predicted indices of stream habitat quality [coefficient of determination (<i>r</i>²) = 0.69, <i>p</i> &lt; 0.05] and macroinvertebrates [percent Ephemeroptera, Plecoptera, and Trichoptera) (<i>r</i>² = 0.49, <i>p</i> &lt; 0.05)], and Shannon diversity (<i>r</i>² = 0.25, <i>p</i> &lt; 0.05). Sub-catchment-scale forest cover was the strongest predictor of overall water quality (<i>r</i>² = 0.35, <i>p</i> &lt; 0.05). Stream habitat quality served as a strong predictor of species richness, percentage Ephemeroptera, Plecoptera, and Trichoptera, and Shannon diversity, suggesting that habitat diversity is important for securing stream ecological health. The findings underscore the importance of catchment-wide forest conservation for the health of stream ecosystems, as it is crucial for maintaining, and enhancing, water quality, while stream buffers are vital for the preservation of the biological integrity and complexity of stream habitats.</p></div>","PeriodicalId":55489,"journal":{"name":"Aquatic Sciences","volume":"88 2","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147560144","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Can adult Ephemeroptera replace nymphs in stream bioassessment? A taxonomic congruence approach in neotropical streams","authors":"Caio Fernando Dotto,&nbsp;Renato Tavares Martins,&nbsp;Gabriela Caroline Mendes,&nbsp;Raul Bismarck Pinedo-Garcia,&nbsp;Ana Maria Pes,&nbsp;Carolina Ferraz Bellodi,&nbsp;Neusa Hamada,&nbsp;Lívia Maria Fusari","doi":"10.1007/s00027-026-01291-6","DOIUrl":"10.1007/s00027-026-01291-6","url":null,"abstract":"<div><p>Monitoring tropical streams uses benthic macroinvertebrates; however, identification constraints and long processing times limit its application. Taxonomic surrogacy has been proposed, but its ecological validity is uncertain. Ephemeroptera are used as bioindicators because their nymphs are highly sensitive to environmental change. However, nymph identification is often limited by fragile structures, whereas adults retain stable traits, and it remains unclear whether imagos can act as surrogates without ecological information loss. Therefore, we evaluated congruence within and between life stages across protected areas and their relationships with environmental variables to assess whether one stage can substitute the other in biomonitoring. We sampled 40 Atlantic Forest streams across two distinct geographic regions, collecting nymphs with D-net and adults with Malaise and Pennsylvania traps. Specimens were identified to the genus level. We evaluated community structure using richness, abundance, and occurrence and tested congruence between life stages and assemblages metrics using Procrustes analysis. We collected 3067 individuals, 1882 nymphs and 1185 adults. Leptophlebiidae and Leptohyphidae were the dominant families for nymphs and adults, respectively. Relations with environmental variables was weak and stage dependent. Abundance and occurrence data were highly congruent within life stages (96–97%). However, cross-stage congruence was low and nonsignificant, suggesting distinct ecological filters between stages, for example, benthic microhabitat for nymphs versus dispersal and phenology for adults, limiting cross-stage surrogacy. Within stages, abundance and occurrence metrics were interchangeable, but adults cannot replace nymph assemblages. Therefore, integrated approaches that combine multiple metrics and life stages enhance the precision and effectiveness of biomonitoring studies.</p></div>","PeriodicalId":55489,"journal":{"name":"Aquatic Sciences","volume":"88 2","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00027-026-01291-6.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147560145","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Variation in taxonomic, functional, and phylogenetic diversity of parasites in Hypostomus spp. (Loricariidae: Hypostominae) from two Neotropical rivers in Brazil","authors":"Atsler Luana Lehun,&nbsp;Aparecida de Fátima Cracco,&nbsp;Larissa Sbeghen Pelegrini,&nbsp;Lidiany Doreto Cavalcanti,&nbsp;Lucas Aparecido Rosa Leite,&nbsp;João Otávio Santos Silva,&nbsp;Gabriela Cássia Reinas,&nbsp;Gabriela Michelan,&nbsp;Vanessa Doro Abdallah,&nbsp;Ricardo Massato Takemoto","doi":"10.1007/s00027-026-01286-3","DOIUrl":"10.1007/s00027-026-01286-3","url":null,"abstract":"<div><p>Understanding how ecological and evolutionary processes shape biodiversity across hierarchical levels is a central goal in ecology, and parasite communities provide a valuable model for investigating assembly rules because they are directly constrained by their hosts. In this study, we investigated how taxonomic (TD), functional (FD), and proxy phylogenetic diversity (PPD) of parasite communities vary across two congeneric fish hosts (<i>Hypostomus hermanni</i> and <i>H. regani</i>) collected from two rivers (Batalha River and Ivaí River). We quantified diversity at multiple organizational levels, including α-diversity within host individuals, β1 variation among host individuals within the same host species, β2 variation between host species, and γ-diversity across habitats. Parasite communities were more similar among host individuals sampled within the same river than between rivers. Alpha diversity differed primarily in TD and FD, with <i>H. hermanni</i> from the Batalha River showing the highest values, whereas αPPD showed limited variation among host species. Beta diversity analyses revealed weak departures from random expectations within host species (β1) but strong differentiation between host species (β2) across TD, FD, and PPD. Overall, our findings indicate that host species remains a central driver of parasite diversity, while highlighting that taxonomic, functional, and phylogenetic facets respond differently to host and habitat-related factors.</p></div>","PeriodicalId":55489,"journal":{"name":"Aquatic Sciences","volume":"88 2","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00027-026-01286-3.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147441138","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hydrogeological functioning of the Massenya floodplain, Lake Chad Basin: insights from stable isotopes and hydrochemistry","authors":"Abdallah Mahamat-Nour,&nbsp;Bichara Djimet D. Bichara,&nbsp;Florence Sylvestre,&nbsp;Bertil Nlend,&nbsp;Christine Vallet-Coulomb,&nbsp;Abderamane Moussa","doi":"10.1007/s00027-026-01284-5","DOIUrl":"10.1007/s00027-026-01284-5","url":null,"abstract":"<div><p>Groundwater resources are a major concern in the Sahel, particularly in the Lake Chad Basin, which covers about 2.5 million km² in sub-Saharan Africa. Despite several studies conducted in this basin, knowledge of many aspects crucial for managing and utilizing water resources remains limited. This is the case for the Massenya floodplain (Chad), which is a hydrological transition zone where significant exchanges occur between surface water and groundwater, thereby helping to mitigate the effects of extreme events. This study used a combined approach based on hydrodynamics (piezometric levels), stable isotopes (δ¹⁸O, δ²H), and hydrochemistry to assess potential groundwater recharge dynamics and water quality using 63 boreholes sampled in March 2024. Water table depth varied from 4.31 m below ground level (m bgl) to 56.51 m bgl, with an average depth of 25.78 m. These variations are primarily driven by surface topography and the complex hydrostratigraphic architecture of the multilayered aquifer system (Continental Terminal, Pliocene, and Quaternary), deposited during successive transgressions and regressions of Lake Chad. Groundwater isotopic signatures reveal contrasting recharge sources, ranging from recent inputs from precipitation and floodwaters, to older waters enriched by evaporation. Observed trends of increasing regional rainfall and floodplain expansion suggest enhanced aquifer recharge. This hypothesis is supported by satellite-derived evidence of flood pulse dynamics, and the presence of modern isotopic signatures in groundwater, indicating a significant contribution of surface water to aquifer replenishment. Hydrochemical analysis shows that Ca–HCO₃⁻ facies dominate, while elevated nitrate concentrations were found in some boreholes located in densely populated areas. Based on major ion concentrations, groundwater quality appeared excellent for irrigation and generally suitable for drinking, except in localized areas affected by nitrate contamination. These results highlight the critical role of floodplains in sustaining aquifer recharge under changing climatic and anthropogenic pressures.</p></div>","PeriodicalId":55489,"journal":{"name":"Aquatic Sciences","volume":"88 2","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147441139","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Temporal variability of dissolved organic matter composition in the hypersaline Mono Lake, California","authors":"Giovanna S. A. Utsumi,&nbsp;James T. Hollibaugh,&nbsp;Amy M. McKenna,&nbsp;Renato M. Castelao,&nbsp;Patricia M. Medeiros","doi":"10.1007/s00027-026-01283-6","DOIUrl":"10.1007/s00027-026-01283-6","url":null,"abstract":"<div><p>Saline lakes are generally characterized by high productivity and accumulation of organic matter, contributing to the global carbon cycle. Mono Lake is an endorheic lake in California (USA) whose geochemistry and microbial community composition have been extensively studied. Less is known about the dissolved organic matter (DOM) composition in this system. Here, we investigated the molecular composition of DOM in Mono Lake using ultrahigh resolution mass spectrometry (FT-ICR MS) to capture patterns of variability in DOM during a transition from monomictic to meromictic conditions in 2017–2018. Dissolved organic carbon (DOC) concentrations were up to twofold higher at ~ 10–15 m in monomictic compared with meromictic conditions. Lake DOM in spring and summer of 2017 was enriched in nitrogen-containing formulae and higher proportions of unsaturated aliphatics, lipid- and protein-like compounds, likely associated with phytoplankton-derived inputs. During fall 2017, lake DOM revealed a more terrestrial signature, and enrichment in sulfur-containing formulae, presumably due to changes in redox condition in the water column. Following prolonged stratification (2018), DOM composition was also influenced by phytoplankton inputs and by the strong redox gradient observed in the lake, with increased relative abundance of S-containing compounds immediately below the pycnocline. During the shift in limnological conditions, Mono Lake DOM remained less aromatic and more reduced than DOM observed in other saline endorheic lakes. These findings shed light on organic carbon cycling in hypersaline lakes, which is important to better constrain contributions of inland aquatic ecosystems to the carbon cycle.</p></div>","PeriodicalId":55489,"journal":{"name":"Aquatic Sciences","volume":"88 2","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00027-026-01283-6.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147440844","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Feeding ecology of anguilliform leptocephali considering the structure and proximate composition of food organisms and gut contents","authors":"Tsutomu Tomoda,&nbsp;Tsuyoshi Watanabe,&nbsp;Kazuaki Tadokoro,&nbsp;Hirofumi Furuita,&nbsp;Nobuto Fukuda,&nbsp;Daisuke Ambe,&nbsp;Takashi Yanagimoto,&nbsp;Yuya Shioura,&nbsp;Satoshi Nagai,&nbsp;Yutaro Nagatomo,&nbsp;Kiyotaka Hidaka,&nbsp;Motoharu Uchida","doi":"10.1007/s00027-026-01281-8","DOIUrl":"10.1007/s00027-026-01281-8","url":null,"abstract":"<div><p>Scanning electron microscope (SEM) observations and component analyses were conducted on the gut contents of wild-caught larvae and cultured larvae that fed on available microorganisms in the water to determine the physical characteristics and nutritional contributions of biological species that are presumed to be food elements of anguilliform leptocephali. There were no traces of food organisms, such as autofluorescence of algae and faecal pellets, or identifiable objects from zooplankton in the gut contents of wild larvae. The gut contents of both wild and cultured larvae were light brown sols or gels and were composed of amorphous substances consisting mainly of carbohydrates, proteins and amino acids. The structural properties of the gut contents of cultured larvae were similar to those of particulate organic matter (POM) in rearing water, and mucus secreted from the intestinal epithelium was also present. These results suggest that low-molecular-weight saccharides, proteins and amino acids produced by algae and bacteria may be among the available nutritional sources of eel larvae and that the mucus layer of the intestinal epithelium contributes to a feeding mode that effectively captures microparticles from environmental water. Taken together, the results of recent surveys suggest that pico- and nanosized POMs, which are ubiquitous in environmental waters and are easily ingested, digested and are absorbable, are a food source of leptocephali. These substances produced by algae and bacteria that account for a high proportion of marine biomass and dissolved organic matter (DOM), may be directly utilized by the intestinal epithelium through pinocytosis without microbial degradation.</p></div>","PeriodicalId":55489,"journal":{"name":"Aquatic Sciences","volume":"88 2","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s00027-026-01281-8.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147362887","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Potentials of machine learning models in estimating the seasonal variability of suspended particulate matters in river ecosystems","authors":"Akash Roy,&nbsp;Kirti Avishek","doi":"10.1007/s00027-026-01272-9","DOIUrl":"10.1007/s00027-026-01272-9","url":null,"abstract":"<div><p>Suspended particulate matter (SPM) is a critical indicator of river water quality, influencing light availability, thermal regimes, and ecosystem functioning, yet its seasonal and interannual dynamics remain poorly quantified in many large river systems. The present study addresses this gap by conducting a seasonally resolved, multi-year (2019–2023) assessment of SPM concentration and surface water temperature (LST_SW) in an understudied stretch of the Ganga River in Sahibganj, India, using Sentinel-2 and Landsat-8 OLI/TIRS imagery. The objectives were to (i) characterize seasonal and interannual variability in SPM under contrasting hydrological seasons, (ii) systematically compare the performance of six machine learning regression models for seasonal SPM prediction, and (iii) evaluate the contribution of spectral indices and ancillary variables to model accuracy. Results reveal pronounced seasonal variability, with reduced SPM concentrations in post-monsoon periods and lower variability in pre-monsoon seasons. Model evaluation across seasons demonstrates that ensemble tree-based approaches, especially random forest (RF) and bagged regression random forest (BGR_RF), consistently outperform linear and boosting-based models, highlighting their robustness for satellite-based SPM prediction in riverine environments characterized by strong seasonal contrasts. While the analysis is constrained by the absence of in situ validation and relies on satellite-derived SPM proxies, the findings underscore the value of integrating multisensor remote sensing with ensemble machine learning for near-real-time and seasonal monitoring of sediment dynamics. Overall, this study presents a transferable and scalable framework for seasonally consistent SPM assessment, supporting improved river water quality monitoring and adaptive management in data-limited regions.</p></div>","PeriodicalId":55489,"journal":{"name":"Aquatic Sciences","volume":"88 2","pages":""},"PeriodicalIF":1.8,"publicationDate":"2026-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147363138","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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}