International Review of Hydrobiology最新文献

{"title":"From Saline to Freshwater: Ecological Shifts, Emerging Fisheries, and Health Risks in Lake Nakuru","authors":"C. S. Nyamweya,&nbsp;C. M. Aura,&nbsp;E. Waithaka,&nbsp;J. M. Njiru,&nbsp;N. K. Momanyi,&nbsp;F. J. Awuor,&nbsp;R. Kundu","doi":"10.1002/iroh.70020","DOIUrl":"https://doi.org/10.1002/iroh.70020","url":null,"abstract":"<div>\u0000 \u0000 <p>Lake Nakuru, historically a hypersaline lake in Kenya's Rift Valley, has undergone a significant ecological transformation due to a sustained saline–freshwater inversion driven by increased rainfall, catchment degradation, and anthropogenic inputs. This study provides a spatially resolved assessment of the lake's current physico-chemical status, biological structure, and socioeconomic dynamics. Results show a dramatic decline in salinity from historical levels of 20–40 to 2.58–2.6 g/kg, weakening the lake's buffering capacity and altering nutrient stoichiometry. Molar TN/TP ratios across all sites were exceptionally low (0.09–0.19), indicating persistent nitrogen limitation and conditions conducive to cyanobacterial dominance. <i>Microcystis</i> comprised 27.58% ± 3.78% of the mean dietary contribution of <i>Oreochromis niloticus</i>, whose proliferation reflects a major shift in the lake's food web. Flamingo populations have declined, likely due to the collapse of their specialized food base. Microbial contamination was highest at river inflow sites. Further, we found elevated concentrations of arsenic and lead in fish tissue, raising critical public health concerns. The emergence of an informal tilapia fishery, driven by ecological changes and declining tourism, has introduced new economic opportunities but also sparked conflict due to its illegality within the protected national park. Vulnerable groups, particularly women, face heightened exposure to both economic instability and health risks. The findings indicate that Lake Nakuru has moved beyond early pollution symptoms into a phase of advanced ecological disruption, underscoring the need for urgent, multisectoral interventions.</p>\u0000 </div>","PeriodicalId":54928,"journal":{"name":"International Review of Hydrobiology","volume":"110 2","pages":"70-82"},"PeriodicalIF":2.3,"publicationDate":"2025-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145761361","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Benthic Diatom Distribution Along a Salinity Gradient in Southeast Caspian Sea Watersheds, Northeast Iran","authors":"Jamileh Panahy Mirzahasanlou,&nbsp;Mojtaba G. Mahmoodlu,&nbsp;Mostafa K. Gharavi,&nbsp;Haniyeh Yusefi,&nbsp;Arsalan Bahalkeh,&nbsp;Mohsen Ghalandar","doi":"10.1002/iroh.70017","DOIUrl":"https://doi.org/10.1002/iroh.70017","url":null,"abstract":"<div>\u0000 \u0000 <p>In coastal areas, salinity is an important variable structuring diatom composition. The Caspian Sea is the world's largest enclosed water body. Variations in benthic diatom composition along salinity gradients were investigated in two important rivers flowing into the southeast Caspian Sea, Gorganroud and Atrak. Epipelic diatom samples were collected from 11 sites from November 2020 to April 2021, along with water samples. One hundred three taxa belonging to 34 genera were identified, of which 47 taxa (≥ 1% relative abundance in ≥ 5 samples were used to model optima and tolerance). The results revealed a shift from freshwater to brackish taxa in dominant and subdominant diatoms with increasing salinity (from 0.02 to 6.64 g.L⁻¹). Taxa such as <i>Amphora inariensis and Cymbella excisa</i> dominated low-salinity sites, while <i>Navicula salinarum, Nitzschia cf. thermaloides</i>, and <i>Haslea spicula</i> increased downstream. Salinity significantly affected the diatom distribution and separated brackish taxa from freshwater ones. However, ammonium and temperature were equally important in Atrak, and phosphate and dissolved oxygen also contributed. However, salinity was not the only factor determining diatom distribution, as nutrients and thermal regime modulated assemblages where salinization was less extreme. Shannon diversity and evenness declined at intermediate salinities (5–7 g.L⁻¹), reflecting Remane's species-poor zone. These findings underscore diatom's value for monitoring salinization and nutrient impacts in Caspian tributaries and support their use in catchment management and long-term ecological assessments.</p>\u0000 </div>","PeriodicalId":54928,"journal":{"name":"International Review of Hydrobiology","volume":"110 2","pages":"57-69"},"PeriodicalIF":2.3,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145761108","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Catchment-Scale Eucalyptus Plantation Effects on Tropical Streams","authors":"Alessandra Peil,&nbsp;Guilherme Sena,&nbsp;Raiane S. Rabelo,&nbsp;Renan de Souza Rezende,&nbsp;Verónica Ferreira,&nbsp;Alan M. Tonin,&nbsp;José Francisco Gonçalves Junior","doi":"10.1002/iroh.70016","DOIUrl":"https://doi.org/10.1002/iroh.70016","url":null,"abstract":"<div>\u0000 \u0000 <p>Forestry plantations occur across the globe, and they are important in many tropical countries for timber supply. Plantations of non-native species, such as those of <i>Eucalyptus</i> species, may greatly affect the functioning of detritus-based ecosystems. However, despite eucalyptus plantations covering about 20 million hectares in tropical and subtropical regions (from a total of about 25 million hectares globally), there is scarce information about their effects on forest stream functioning. Our aim was to assess the effects of catchment-scale eucalyptus plantations (with native riparian buffers) on the functioning of tropical streams in the Cerrado biome. For that, three streams in catchments with eucalyptus plantations (eucalyptus streams) and three streams in catchments with native vegetation (native streams) were compared regarding water characteristics, litter inputs (vertical and lateral), decomposition of leaf litter (from a common native species, an eucalyptus species used in plantations, and a palatable exotic species) and litter-associated aquatic communities. We hypothesized that catchment-scale <i>Eucalyptus</i> plantations negatively affect stream characteristics (reduced water flow, heightened water acidity), litter inputs, aquatic communities, and litter decomposition in streams because dense, even-aged monocultures of eucalyptus trees have higher water consumption rates and produce recalcitrant litter. We also hypothesized that the effects of plantations would be stronger on shredders, as they are directly influenced by changes in litter input compared to other functional feeding groups. Finally, we hypothesized that plantation impacts on leaf litter decomposition would be stronger for palatable leaf litter, where invertebrate shredders play a major role, than for more recalcitrant and less palatable leaf litter. We found lower dissolved oxygen concentrations, lateral litter inputs, and litter decomposition in eucalyptus streams than in native streams. Conversely, fungal biomass on decomposing litter did not differ between eucalyptus streams and native streams. <i>Eucalyptus</i> plantations reduced overall invertebrate densities but did not affect shredder densities. Our study shows that catchment-scale eucalyptus plantations can change water characteristics and litter inputs to streams, thus slowing down litter decomposition in tropical streams, even when a native buffer is present. Increasing the width of the native buffer vegetation may contribute to increasing its protective role.</p>\u0000 </div>","PeriodicalId":54928,"journal":{"name":"International Review of Hydrobiology","volume":"110 2","pages":"42-56"},"PeriodicalIF":2.3,"publicationDate":"2025-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145754625","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Trichoptera, Odonata, and Diptera as Efficient Surrogate Taxa for Monitoring Macroinvertebrate Assemblages in Urban Amazonian Streams","authors":"Sheyla R. M. Couceiro,&nbsp;Neusa Hamada,&nbsp;Karina Dias-Silva,&nbsp;Renato T. Martins","doi":"10.1002/iroh.70015","DOIUrl":"https://doi.org/10.1002/iroh.70015","url":null,"abstract":"<div>\u0000 \u0000 <p>Using a subset of the aquatic insect assemblage (e.g., Trichoptera, Odonata, and Diptera) and less refined identifications can reduce identification time and costs in aquatic biomonitoring. Using data collected from urban Amazonian streams, we evaluated the congruence between the macroinvertebrate fauna and the Trichoptera, Odonata, and Diptera subsets at the family and genus level. In addition, we evaluated the congruence between the abiotic and macroinvertebrate data sets. Data were collected during the dry and rainy seasons of 2004/2005 and the dry season of 2010. Our results indicate high intra-annual congruence for both abiotic and biotic (occurrence and abundance) variables. However, low interannual congruence was observed. Interannual congruence for biotic variables was slightly above 70%. Macroinvertebrate occurrence and abundance of all taxa showed a moderate correlation with abiotic data. The highest level of congruence with abiotic data was observed for the abundance of Odonata genera in 2010, while the lowest was found for the abundance of Diptera family in 2010. The concordance values between biotic and abiotic data were generally similar when considering both abundance and occurrence data. In all seasons, congruence between genera and families was greater than 90% for abundance and occurrence data. Our results suggest that assessments based on macroinvertebrate family abundance and occurrence may be sufficient for biomonitoring and that the families of Trichoptera, Odonata, and Diptera represent most of the total invertebrate assemblage in the streams studied.</p>\u0000 </div>","PeriodicalId":54928,"journal":{"name":"International Review of Hydrobiology","volume":"110 2","pages":"33-41"},"PeriodicalIF":2.3,"publicationDate":"2025-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145761460","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Research on aquatic ecosystems - freshwater and marine environments and their management","authors":"","doi":"10.1002/iroh.70013","DOIUrl":"https://doi.org/10.1002/iroh.70013","url":null,"abstract":"","PeriodicalId":54928,"journal":{"name":"International Review of Hydrobiology","volume":"110 1","pages":""},"PeriodicalIF":0.9,"publicationDate":"2025-06-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/iroh.70013","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144292675","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Rotifera Occurrence and Diversity in the Groundwater Wells of a Major European Wetland Complex","authors":"Jolanta Ejsmont-Karabin,&nbsp;Maciej Karpowicz","doi":"10.1002/iroh.70014","DOIUrl":"https://doi.org/10.1002/iroh.70014","url":null,"abstract":"<div>\u0000 \u0000 <p>Rotifera are found in nearly all terrestrial and freshwater habitats, however, the knowledge about rotifers in groundwater is scarce. To enhance our understanding of Rotifera distribution in groundwater in the lowland regions of Central Europe, we investigated 101 wells throughout the Biebrza Valley—one of Europe's largest wetland complexes. Rotifers were found in most of the studied wells (97%); however, only 22 Monogononta species were identified. The majority of these were littoral species commonly associated with surface water macrophytes, suggesting passive transport from the river network rather than active colonization or specialization for subterranean life. No strictly stygobiontic (obligate groundwater) or stygophilic (preferring groundwater) Rotifera species were found. Instead, our results indicate a high prevalence of stygoxenic species—organisms that occur in groundwater environments only incidentally. Species richness was low compared to surface or transitional habitats such as springs and the hyporheic zone, which showed much greater rotifer diversity. These findings suggest that while rotifers can occur in groundwater, their ecological traits favor opportunistic colonization over groundwater specialization.</p>\u0000 </div>","PeriodicalId":54928,"journal":{"name":"International Review of Hydrobiology","volume":"110 1","pages":"22-28"},"PeriodicalIF":0.9,"publicationDate":"2025-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144292307","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Landscape Change and Threats to Conservation of River Dolphin Inia araguaiaensis (Cetacea: Iniidae) in the Brazilian Savanna","authors":"Cristiane Gonçalves de Moraes,&nbsp;Miriam Marmontel,&nbsp;Mariana Paschoalini Frias,&nbsp;Marcelo Oliveira-da-Costa,&nbsp;Paulo De Marco Junior","doi":"10.1002/iroh.70011","DOIUrl":"https://doi.org/10.1002/iroh.70011","url":null,"abstract":"<p>River dolphins are the least studied and most threatened cetaceans. Anthropogenic activities, including habitat fragmentation, pollution, and declining fish stocks, pose significant challenges to their survival. This study evaluated the effects of landscape changes resulting from human activity on the encounter rates of the putative species of Araguaia boto, <i>Inia araguaiaensis</i>, during the dry season. We observed heterogeneous distribution patterns of Araguaia boto along the Araguaia River, with a high occurrence in the middle stretch of the river. Regression analyses revealed a negative correlation between encounter rates and anthropogenic activities, indicating the possible influence of landscape change on species distribution. Our findings underscore the importance of conserving cetaceans as indicators of environmental quality and river ecosystem dynamics. Understanding the correlation between human activity, habitat alteration, and boto distribution is crucial for effective conservation strategies in river ecosystems.</p>","PeriodicalId":54928,"journal":{"name":"International Review of Hydrobiology","volume":"110 1","pages":"13-21"},"PeriodicalIF":0.9,"publicationDate":"2025-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/iroh.70011","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144292789","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Long-Term Effects of Land Use and Cover Change and Dam Rupture on Ichthyofauna in a Neotropical Stream","authors":"Nícholas de P. Nicomedes,&nbsp;Thiago M. R. Santos,&nbsp;Luís G. N. de Carvalho,&nbsp;Beatriz C. G. Prieto,&nbsp;Camila S. Bento,&nbsp;Larissa L. M. Silva,&nbsp;Flavia C. de Paiva,&nbsp;Natalia S. Alves,&nbsp;Welber S. Smith","doi":"10.1002/iroh.70006","DOIUrl":"https://doi.org/10.1002/iroh.70006","url":null,"abstract":"<p>This study evaluates land use and land cover (LULC) changes and their impacts on the fish community of a neotropical stream in the Sorocaba River basin, Brazil, from 2006 to 2023. The watershed experienced landscape changes over time, categorized into four periods: rural interventions, urban interventions, restorative interventions, and post-restorative interventions. The objective was to understand LULC changes and their ecological consequences, focusing on fish assemblages. There were significant differences in land use over time. Forested areas had the most substantial impact on the fish community, explaining 32.7% of the variation, being the only significant LULC variable. LULC changes reflected a considerable impact of human interventions, notably the increase in non-vegetated areas from 2.3% during rural interventions to 46.9% during urban interventions, reflecting environmental degradation caused by urbanization. The fish community was severely affected after the dam collapse in 2013, leaving only one surviving species, <i>Phalloceros harpagos</i>. However, after restoration actions in 2014–2015, some species, such as <i>Astyanax lacustris</i> and <i>Psalidodon fasciatus</i>, returned, and new species, such as <i>Hyphessobrycon bifasciatus</i> and <i>Psalidodon anisitsi</i>, were also recorded. In contrast, species like <i>Coptodon rendalli</i> and <i>Geophagus iporangensis</i> were no longer found. These findings highlight the importance of restoration actions for at least partially recovering aquatic biodiversity in ecosystems impacted by human activities.</p>","PeriodicalId":54928,"journal":{"name":"International Review of Hydrobiology","volume":"110 1","pages":"5-12"},"PeriodicalIF":0.9,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/iroh.70006","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144292648","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Research on aquatic ecosystems – freshwater and marine environments and their management","authors":"","doi":"10.1002/iroh.202386010","DOIUrl":"https://doi.org/10.1002/iroh.202386010","url":null,"abstract":"","PeriodicalId":54928,"journal":{"name":"International Review of Hydrobiology","volume":"108 6","pages":"61"},"PeriodicalIF":0.9,"publicationDate":"2024-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/iroh.202386010","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143252815","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Land Use Effects on Water Chemistry in Lagos Lagoon, Nigeria (West Africa)","authors":"Blessing Chinomso Okorie,&nbsp;Koffi Komoe,&nbsp;Ikenna Charles Onyema,&nbsp;Hendrik Schubert,&nbsp;Pierre Anthony Mendy,&nbsp;Kwasi Aning Dwumah","doi":"10.1002/iroh.202402172","DOIUrl":"https://doi.org/10.1002/iroh.202402172","url":null,"abstract":"<p>Understanding the effects of changes in land use patterns in the catchment area on water quality is crucial for effectively protecting aquatic resources. As transition zones between freshwater and the marine realm, Lagoon systems are especially vulnerable to anthropogenic influence due to their limited water exchange and challenging salinity regimes. To assess the environmental consequences of land use changes on water quality parameters under subtropical African conditions, 12 sites in Lagos Lagoon were sampled monthly over an entire year, covering the wet and dry seasons. The relationships between land use patterns and water quality were studied by combining seasonal water analysis results with GIS mapping based on satellite images. The results of the monthly water analysis showed a large degree of seasonality effects on almost all parameters but also some site-specific features pointing to local dominance of catchment area-related impacts. To unravel them, correlations between water parameters and land use patterns were analyzed based on a rough but robust classification. The land use forms were divided into five categories: waterbody, bare land, forest, urban area, and wetland. Independent of the restricted range of land use pattern variability covered by this study, several significant correlations between land use form and water quality parameters were found. Most of them are exclusively restricted to either the wet or dry season. Consistent season-independent significant correlations were found between the percentage of urban area and dissolved oxygen concentration. For wetlands, such consistent and significant correlations were found with nitrate, chemical oxygen demand, and turbidity. The findings provide first insights into the impact of land use changes on lagoon water quality under subtropical biodiversity of these systems and aquatic resources in general.</p>","PeriodicalId":54928,"journal":{"name":"International Review of Hydrobiology","volume":"108 6","pages":"65-75"},"PeriodicalIF":0.9,"publicationDate":"2024-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143252770","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}