Lakes and Reservoirs: Research and Management最新文献

{"title":"Aligning small indigenous fish species (SIS) in policy and management for enhanced food security and nutrition: The case of the Kenyan Lake Victoria Omena fishery","authors":"Christopher Mulanda Aura,&nbsp;Horace Owiti,&nbsp;Chrisphine Nyamweya,&nbsp;Cyprian O. Odoli,&nbsp;Julia Akinyi Obuya,&nbsp;Zachary Ogari,&nbsp;James M. Njiru,&nbsp;Martin Van der Knaap","doi":"10.1111/lre.12399","DOIUrl":"10.1111/lre.12399","url":null,"abstract":"<p>Fisheries governance uses policy and statutory documents to improve governance on fish ecology, harvesting, trade and consumption by identifying and addressing gaps regarding inefficiencies, inequity and post-harvest losses. The current study examines existing policies and institutional documents on fisheries, health and trade to assess the level of inclusion of small indigenous fish species (SIS), especially Omena, as a means of guiding governance interventions for sustained livelihoods of fishing communities in Lake Victoria. A content-analysis review was conducted on all the fisheries and nutritional policy documents related to Lake Victoria fishery to ascertain the need for their integration into fisheries governance. From the scoring scale, where zero (0) implies no integration and three (3) implies high integration, the study results indicated very low levels of integration across health, fisheries and trade relating to small fish species. Further, the management plans and regulations/guidelines exhibited a relatively higher level of integration than did policies and laws. There is need for a more targeted approach for streamlining the existing policy documents to realize the untapped potential contribution of SIS towards food and nutritional security.</p>","PeriodicalId":39473,"journal":{"name":"Lakes and Reservoirs: Research and Management","volume":"27 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/lre.12399","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115411257","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Aspects of the biology and population structure of Oreochromis niloticus, Coptodon zillii and Oreochromis leucostictus tilapia in Lake Naivasha, Kenya","authors":"Edwine Yongo,&nbsp;Simon W. Agembe,&nbsp;Julius O. Manyala,&nbsp;Edna Waithaka","doi":"10.1111/lre.12398","DOIUrl":"10.1111/lre.12398","url":null,"abstract":"<p>The Nile tilapia (<i>Oreochromis niloticus</i>), Redbelly tilapia (<i>Coptodon zillii</i>) and Blue spotted tilapia (<i>Oreochromis leucostictus</i>) were introduced into Lake Naivasha in the 1950s to diversify and boost the lake fisheries. These species have since been exploited in the commercial gillnet fishery. The fish stocks, however, are currently facing problems of pollution, wetland degradation and intense fishing pressures. Accordingly, the present study investigated some aspects of the biology and population structure of the three tilapiine species in light of changing lake conditions. Fish samples were collected from January to December 2019 using multifilament gillnets of 2.0-to-6.0-inch mesh sizes. Immediately after their capture, the fish specimens were transported to the lab for morphometric measurements and analysis of maturity. The highest and lowest mean (±SD) total length (TL) were exhibited by <i>O</i>. <i>niloticus</i> (22.9 ± 5.2 cm) and <i>C</i>. <i>zillii</i> (14.5 ± 2.1 cm), respectively. Similarly, <i>O</i>. <i>niloticus</i> exhibited a higher mean weight (268.4 ± 18.0 g) and body depth (7.6 ± 2.5 cm), compared to the other species. <i>O</i>. <i>niloticus</i> exhibited an isometric growth pattern, while <i>C</i>. <i>zillii</i> and <i>O</i>. <i>leucostictus</i> exhibited negative allometric growth. The fish species were in good condition, with mean condition factors of 1.59 ± 0.07, 1.51 ± 0.06 and 1.23 ± 0.03 for <i>C</i>. <i>zillii</i>, <i>O</i>. <i>leucostictus</i> and <i>O</i>. <i>niloticus</i>, respectively. Furthermore, the condition factors for <i>O</i>. <i>leucostictus</i> and <i>O</i>. <i>niloticus</i> varied by size class, exhibiting a decreasing trend with increased fish size. The male:female sex ratio revealed significantly more males than females for <i>O</i>. <i>niloticus</i> (2.30:1.0) and <i>O</i>. <i>leucostictus</i> (2.36:1.0), although not for <i>C</i>. <i>zillii</i> (1.15:1.0). <i>O</i>. <i>niloticus</i> (28.0–29.0 cm TL) matured at a larger size, followed by <i>O</i>. <i>leucostictus</i> (21.0–26.0 cm TL), and <i>C</i>. <i>zillii</i> (15.0–17.0 cm TL). In comparison, values of length-weight parameters, condition factor, sex ratio and size at first maturity of the studied fishes varied in Lake Naivasha, Victoria, Albert and George. The gillnet mesh ≤3.0″ mainly targeted small-sized immature fish, while mesh ≥4″ targeted mature fish, particularly <i>O</i>. <i>niloticus</i>. It was concluded that gillnets with ≥4.0″ mesh could safely be applied for this fishery in Lake Naivasha, whereas the use of smaller mesh should be controlled to protect the juveniles as a means of maintaining sustainable fisheries. Furthermore, the present study also provided useful information, including size at maturity that is vital for setting mesh size for managing the lake fishery.</p>","PeriodicalId":39473,"journal":{"name":"Lakes and Reservoirs: Research and Management","volume":"27 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-03-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/lre.12398","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125861542","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of seasonal hypoxia on macroinvertebrate communities in a small reservoir","authors":"David O. Lucchesi,&nbsp;Steven R. Chipps,&nbsp;David A. Schumann","doi":"10.1111/lre.12395","DOIUrl":"10.1111/lre.12395","url":null,"abstract":"<p>Localized hypoxia can reduce available habitat, restrict movement and limit the abundance of aquatic invertebrates. Although cultural eutrophication, coupled with the effects of climate change, is likely to increase the frequency and extent of hypoxia in aquatic ecosystems, little is known about how oxygen gradients in small reservoirs influence spatial distribution and abundance of aquatic invertebrates. The present study evaluated the effects of environmental and biological attributes on seasonal and spatial variation of macroinvertebrates and explored how hypoxic conditions influenced littoral, benthic and pelagic macroinvertebrate communities in Lake Alvin, South Dakota. Data on reservoir conditions, in conjunction with macroinvertebrate sampling from May to October 2009–2011, were applied in an information theoretic approach to evaluate factors affecting invertebrate abundance. Hypoxic conditions were present from May to September in the lacustrine zone impacting 10%–39% of the water column. Benthic invertebrates were typically absent from the lacustrine zone during periods of severe hypoxia and were most abundant in the shallow, well-oxygenated riverine zone. Littoral invertebrates were negatively related to the per cent of the hypoxic water column, suggesting fish, confined to shallow waters by hypoxia, may be consuming a larger portion of littoral invertebrates in their diets. Cladocera and Copepoda densities were influenced primarily by water depth and monthly precipitation. The larger size of <i>Daphnia</i> found in the hypoxic-prone transitional and lacustrine zones suggested low oxygen concentrations may provide a refuge from fish predation. The results of the present study demonstrated spatial variations in near-bottom oxygen concentrations were important predictors of macroinvertebrate and zooplankton abundance and size structure in Lake Alvin and that macroinvertebrates, particularly benthic and littoral invertebrates, could benefit from measures taken to reduce summer hypoxia.</p>","PeriodicalId":39473,"journal":{"name":"Lakes and Reservoirs: Research and Management","volume":"27 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/lre.12395","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128348232","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Post-filling phase ichthyofaunal community and fishery potential of Chitsuwa Reservoir, a small tropical reservoir in Zimbabwe","authors":"Takudzwa C. Madzivanzira,&nbsp;Chipo Mungenge,&nbsp;Adroit T. Chakandinakira,&nbsp;Nyasha Rugwete,&nbsp;Blessing Kavhu","doi":"10.1111/lre.12394","DOIUrl":"10.1111/lre.12394","url":null,"abstract":"<p>Many small reservoirs exist throughout Southern Africa, and with adequate management have the potential to contribute significantly to food security. The fisheries and limnology of the newly created Chitsuwa Reservoir in Zimbabwe were studied with the objective of generating information to support the development, management and sustainable use of fisheries to enhance the socio-economic status of riparian communities. Based on gill nets of various mesh sizes, it was confirmed that the reservoir is presently inhabited by a fairly diverse fish community comprising ten species belonging to five families (<i>Clarias gariepinus</i>; <i>Coptodon rendalli</i>; <i>Labeo cylindricus</i>; <i>Marcusenius macrolepidotus</i>; <i>Micropterus salmoides</i>; <i>Momyrus longirostris</i>; <i>Oreochromis mossambicus</i>; <i>Oreochromis niloticus</i>; <i>Serranochromis microcephalus</i>; and <i>Tilapia sparrmanii</i>). <i>Oreochromis niloticus</i> dominated the reservoir with respect to both abundance, biomass and catch. The index of relative importance revealed <i>O</i>. <i>niloticus</i> and <i>M</i>. <i>macrolepidotus</i> were the most important species. Results from the Canonical Correspondence Analysis revealed a clear division of the fish species that followed the environmental variables. Although fisheries may benefit from the invasive <i>M</i>. <i>salmoides</i> and the established <i>O</i>. <i>niloticus</i>, their presence in the reservoir is a cause for concern for conserving native congeneric species that risk extirpation through documented mechanisms. The results of the present study suggest sound management of the reservoir is required to raise its potential of supporting the livelihoods of the surrounding communities with a predicted annual fish yield of 61.5 t/year. Management of this reservoir should involve the local communities, empowering them so that they practice sustainable non-destructive fishing methods.</p>","PeriodicalId":39473,"journal":{"name":"Lakes and Reservoirs: Research and Management","volume":"27 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-01-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/lre.12394","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124526704","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Post-impoundment study of the fish communities of Tugwi-Mukosi Reservoir, Zimbabwe","authors":"Takudzwa C. Madzivanzira,&nbsp;Lindah Mhlanga,&nbsp;Maxwell Barson,&nbsp;Lightone Marufu,&nbsp;Pamela Tendaupenyu,&nbsp;Newman Songore,&nbsp;Tamuka Nhiwatiwa","doi":"10.1111/lre.12393","DOIUrl":"10.1111/lre.12393","url":null,"abstract":"<p>A post-impoundment ichthyofaunal survey was carried out in 2017 in Tugwi-Mukosi Reservoir using gill nets, seine net and fyke nets. The objective was to determine the present fish assemblages after impoundment of the reservoir in order to provide a baseline study that could be used to inform management decisions and for comparison with future predicted ecological changes associated with fishery development. The fish community composition was fairly diverse, comprising of 11 species belonging to four families, including Cichlidae (<i>Oreochromis mossambicus</i>; <i>Coptodon rendalli</i>; <i>Tilapia sparmanii</i>), Momyridae (<i>Marcusenius macrolepidotus</i>), Cyprinidae (<i>Labeo cylindricus</i>; <i>Enteromius paludinosus</i>; <i>E</i>. <i>afrohamiltoni</i>; <i>E</i>. <i>topinni</i>; <i>E</i>. <i>trimaculatus</i>; <i>Engraulicypris brevianalis</i>) and Clariidae (<i>Clarias gariepinus</i>). <i>Oreochromis mossambicus</i> was present at all sampled sites, with only two species (<i>O</i>. <i>mossambicus</i>; <i>M</i>. <i>macrolepidotus</i>) sampled downstream of the reservoir. Twenty-two prey/forage categories were observed in the guts of analysed fish, with macrophytes having the highest frequency of occurrence (90%). All the body condition values of fish from the reservoir exceeded one, and the estimated fish yield is 33.34 t/year. Collective efforts involving various stakeholders should be made to ensure the reservoir develops into a successful fishery resource, while also serving other purposes.</p>","PeriodicalId":39473,"journal":{"name":"Lakes and Reservoirs: Research and Management","volume":"27 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/lre.12393","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128854068","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Complex interactions between benefits, ecosystem services and landscape dynamics: A synthesis of Lake Malombe, Malawi","authors":"Rodgers Makwinja,&nbsp;Seyoum Mengistou,&nbsp;Emmanuel Kaunda,&nbsp;Tena Alamirew","doi":"10.1111/lre.12392","DOIUrl":"10.1111/lre.12392","url":null,"abstract":"<p>African inland freshwater lakes experience a high level of exploitation, as evidenced by a decline in biodiversity, food production and rising poverty. Lake Malombe in Malawi provides the best example of this situation. The lake catchment is severely degraded and faces profound biodiversity losses. Households in the catchment are caught in a vicious cycle of poverty. Management decisions regarding Lake Malombe involve choices that reflect opportunity costs among the complex socio-ecological interactions that are often unnoticeable. Ecosystem managers unintentionally make decisions that diminish the value of some critical ecosystem services (ESs), while enhancing others. The present study used geospatial and participatory approaches to explore complex interactions between benefits, ESs and landscape dynamics. The study findings indicate the ecosystem provisioning services (EPSs) are the main livelihood sustenance vehicle for Lake Malombe's local population. The increased cultivated land from 52,932 to 78,983 ha and decreased forest land from 56,235 to 8585 ha between 1989 and 2019 are linked to EPSs changes at the expense of regulatory, supporting and cultural ecosystem services. The findings of the present study suggest an important need to balance the opportunity costs among the complex ESs dynamics and landscape transformation as a means of achieving management policy efficiency while at the same time also avoiding adverse outcomes from human activities.</p>","PeriodicalId":39473,"journal":{"name":"Lakes and Reservoirs: Research and Management","volume":"27 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/lre.12392","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123614516","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Population characteristics and potential factors influencing recruitment variability of blue catfish, channel catfish and flathead catfish in Thunderbird Reservoir, Oklahoma","authors":"Austin D. Griffin,&nbsp;Richard A. Snow,&nbsp;Michael J. Porta","doi":"10.1111/lre.12390","DOIUrl":"https://doi.org/10.1111/lre.12390","url":null,"abstract":"<p>Blue catfish (<i>Ictalurus furcatus</i>), channel catfish (<i>Ictalurus punctatus</i>) and flathead catfish (<i>Pylodictis olivaris</i>) are popular sport fishes throughout North America, and are therefore intensively managed by some natural resource agencies. Although catfish fisheries rely on sufficient natural reproduction and recruitment to sustain these populations, few studies have evaluated the variables affecting catfish recruitment. Thus, the objectives of this study were to describe population characteristics (age, size structure, condition, growth, mortality and recruitment) of blue catfish, channel catfish and flathead catfish in Thunderbird Reservoir, Oklahoma, and evaluate the effects of hydrology, water quality and temperature on year-class strength. During 2017 and 2018, 235 blue catfish, 194 channel catfish and 120 flathead catfish were collected and aged using otoliths. In general, these catfish species in Thunderbird Reservoir were slow growing, long-lived, had low mortality rates and experienced variable recruitment. Blue catfish recruitment was lower in years with higher average January air temperatures. Channel catfish recruitment was higher in years with increased average annual and spring/summer exchange rate and increased spring/summer average reservoir water volume (ha-m). Conversely, higher annual average total hardness (mg/L) resulted in decreased recruitment for channel catfish. Flathead catfish recruitment exhibited a minimal negative impact with increased annual reservoir volume (ha-m). The present study is among the first to describe potential variables influencing year-class formation of blue catfish, channel catfish and flathead catfish in reservoirs. Although the variables found to influence catfish recruitment are outside the control of fisheries managers, biologists should promote downstream angling opportunities for blue catfish that escape during reservoir water release events and stock channel catfish in systems with consistently high total water hardness in order to maximize fishing opportunities. Further, they can use the results of this study to manage angler expectations following periods of low recruitment.</p>","PeriodicalId":39473,"journal":{"name":"Lakes and Reservoirs: Research and Management","volume":"27 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/lre.12390","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91918670","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Water hyacinth (Eichhornia crassipes) infestation cycle and interactions with nutrients and aquatic biota in Winam Gulf (Kenya), Lake Victoria","authors":"Dennis Otieno,&nbsp;Hilda Nyaboke,&nbsp;Chrisphine Sangara Nyamweya,&nbsp;Cyprian Ogombe Odoli,&nbsp;Christopher Mulanda Aura,&nbsp;Nicholas Otieno Outa","doi":"10.1111/lre.12391","DOIUrl":"10.1111/lre.12391","url":null,"abstract":"<p>Lake Victoria, like many other lakes in Africa, is affected by water hyacinth that reside in several bays for the majority of the year. The weed affects several economic activities of the local communities and denies revenue to the government from blue economic activities related to the lake. The present study examined the interaction of water hyacinth with biotic and abiotic factors and the efficiency of introduced weevils to better control this invasive weed. Water quality samples were collected and compared from the time of water hyacinth re-emergence and sinking within the Winam Gulf of Lake Victoria. The present study was divided into three phases with an interval of 2 months. Water hyacinth was collected, and the damages resulting from the weevils to the hyacinth, as well as the number of weevils, was recorded and analysed. Fish samples were collected with experimental gill nets. The collected water samples was analysed for the aquatic plant nutrient ammonium, soluble reactive phosphorus, nitrates and nitrites. Data were analysed using R package. The results of the present study indicated that the weevils inhibited nutrient uptake by hyacinth by 17% within the first 4 weeks. The hyacinth subsequently increased the nutrient levels in the gulf by threefold after their decay and sinking. Weevils also increased the sinking rate of water hyacinth through the destruction of their petioles and leaves. One hundred and ninety-four more fish were observed in the experimental nets during the weed infestation, compared to periods when the weed was absent within the gulf. The major conclusions were that water hyacinth impacts both biotic and abiotic factors, and that the weevils alone are unable to eradicate the weed.</p>","PeriodicalId":39473,"journal":{"name":"Lakes and Reservoirs: Research and Management","volume":"27 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/lre.12391","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125453419","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Degradation of dam reservoirs under the influence of mining subsidence in Upper Silesian Coal Basin, South Poland","authors":"Joanna Kidawa,&nbsp;Tadeusz Molenda","doi":"10.1111/lre.12388","DOIUrl":"https://doi.org/10.1111/lre.12388","url":null,"abstract":"<p>Exploitation of mineral resources can result in dramatic multidirectional changes in the natural environment in mining areas, with the changes being particularly evident in the form of land degradation. One of the consequences of underground mining is subsidence of the overlying surface of the land area. The greatest subsidence typically occurs when the mining operation is carried out with a longwall top coal caving process, which can result in subsidence basin deformation developing on the surface. This development can lead to a change in natural landforms. As a consequence of the development of subsidence basins in the present study, the maximum depth in the Upper Silesian Coal Basin may exceed 30-m, which can also change the hydrological conditions of the area. Development of subsidence basins can often lead to changes in the morphometric parameters of the existing hydrographic objects, a phenomenon that also applies to dam reservoirs. As a result of land subsidence, the depth and surface area of hydrographic objects can increase, with the maximum depth point moving deeper into the reservoir outside the frontal barrage zone, with changes also occurring in the reservoir tank morphometry. In extreme cases, the barrage may stop water damming, being located outside the reservoir zone, meaning the tank's water management function is lost. All the reservoirs in the current study are located in the Upper Silesian Coal Basin in southern Poland, which is currently the only significant coal-mining centre in Europe, with the surface area of the basin being 7490 km².</p>","PeriodicalId":39473,"journal":{"name":"Lakes and Reservoirs: Research and Management","volume":"26 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91806412","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bacterial decomposition of allochthonous organic matter in shallow subtropical lakes","authors":"Pâmela R. Gayer,&nbsp;Pablo S. Guimarães,&nbsp;Edélti F. Albertoni,&nbsp;Luiz U. Hepp","doi":"10.1111/lre.12389","DOIUrl":"https://doi.org/10.1111/lre.12389","url":null,"abstract":"<p>Shallow lakes favour the development of aquatic macrophytes that can influence the limnological characteristics of these environments. In addition to macrophytes, allochthonous organic matter contributes to the metabolism of lakes through the bed of decomposing detritus. Among the decomposing microorganisms, bacteria can be important in the processing of organic matter when the abundance of fungi and invertebrates is low. The present study evaluated the effects of macrophyte coverage on bacterial-mediated leaf decomposition of allochthonous debris in shallow subtropical lakes. Litter bags were incubated with senescent leaves of <i>Erythrina crista</i>-<i>galli</i> in six shallow lakes, three with high (HML) and three with low (LML) macrophyte coverage. After 2, 7, 15 and 35 days of incubation, a set of litter bags was removed from each lake for bacterial, environmental and mass-loss analyses. Decomposition rates were higher in the LML (49% of remaining mass), compared to the HML (63% of remaining mass). The bacterial density and biomass were higher in the LML. Limnological variables influenced bacterial morphotypes, especially branched filament. Thus, the high coverage of aquatic macrophytes can be a main factor influencing the bacterial colonization in the debris, delaying the decomposition process in these ecosystems.</p>","PeriodicalId":39473,"journal":{"name":"Lakes and Reservoirs: Research and Management","volume":"26 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90130767","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}