Journal of Great Lakes Research最新文献_第10页

Seasonality interacts with mixed land use and conservation in controlling patterns of nutrient and pathogen export from agricultural watersheds 季节性与混合土地利用和保护在控制农业流域养分和病原体输出模式方面相互作用

IF 2.4 3区环境科学与生态学 Q3 ENVIRONMENTAL SCIENCES

Journal of Great Lakes Research

Pub Date : 2025-06-04 DOI: 10.1016/j.jglr.2025.102607

Anna E.S. Vincent , Jennifer L. Tank , Ursula H. Mahl , Kyle Bibby

Fertilizer runoff is a significant source of nutrients to streams draining agricultural watersheds and results in numerous downstream impacts including eutrophication and coastal hypoxia. Additionally, pathogen export linked to manure application poses a threat to human health and results in recreational closures. Agricultural conservation practices, such as the planting of winter cover crops (CC), can reduce nutrient losses to streams, but their impacts on pathogen transport remain understudied. From 2019 to 2022, we sampled every 2 weeks in three subwatersheds of the Paw Paw River Basin (Michigan, USA) to assess the role of CC in reducing dissolved nitrate (NO₃^–-N), ammonium (NH₄⁺-N), soluble reactive phosphorus (SRP), and the fecal bacterium Escherichia coli export. The three subwatersheds contain varying levels of agricultural land use, ranging from 41 to 77 %. Water column NO₃^–-N (mg L^-1) peaked during the winter and spring fallow season, while E. coli (CFU 100 mL⁻¹) peaked during summer, which points to different drivers controlling NO₃^–-N and pathogen export throughout the year. Increased daily yields of dissolved nutrient tended to coincide with more agricultural land cover; however, we measured highest daily yields of E. coli in the watershed with lowest agricultural land cover. Planting CC reduced NO₃^–-N yield by 10–31 %, NH₄⁺-N yield by 19–22 %, SRP yields by 3–11 %, and E. coli yields by 17–48 %, and therefore is effective at mitigating both nutrient and pathogen export from agricultural landscapes, but additional work is required to fully understand the dynamics (timing and drivers) controlling E. coli export in watersheds of mixed land use.

肥料径流是农业流域排水的重要营养来源，并导致许多下游影响，包括富营养化和沿海缺氧。此外，与施用肥料有关的病原体出口对人类健康构成威胁，并导致娱乐场所关闭。农业保护措施，如种植冬季覆盖作物（CC），可以减少河流的养分损失，但它们对病原体运输的影响仍未得到充分研究。从2019年到2022年，我们在美国密歇根州的Paw河流域的三个子流域每2周采样一次，以评估CC在减少溶解硝酸盐（NO3——N）、铵（NH4+-N）、可溶性活性磷（SRP）和粪便大肠杆菌出口中的作用。这三个子流域的农业用地比例各不相同，从41%到77%不等。水柱NO3—N （mg L-1）在冬季和春季休闲季节达到峰值，大肠杆菌（CFU 100 mL−1）在夏季达到峰值，说明全年控制NO3—N和病原菌输出的驱动因素不同。溶解养分日产量的增加往往与农业土地覆被的增加相一致；然而，我们在农业土地覆盖最低的流域测量了最高的大肠杆菌日产量。种植CC可使NO3—N产量降低10 - 31%，NH4+-N产量降低19 - 22%，SRP产量降低3 - 11%，大肠杆菌产量降低17 - 48%，因此可有效减少农业景观中的养分和病原体输出，但需要进一步研究控制混合土地利用流域大肠杆菌输出的动态（时间和驱动因素）。

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引用次数: 0

Predation on fish larvae by black-striped pipefish (Syngnathus abaster) during the breeding season in invaded fresh waters of the Dnieper River basin 第聂伯河入侵淡水区繁殖季节黑条纹管鱼对鱼类幼鱼的捕食

IF 2.4 3区环境科学与生态学 Q3 ENVIRONMENTAL SCIENCES

Journal of Great Lakes Research

Pub Date : 2025-06-04 DOI: 10.1016/j.jglr.2025.102613

Alexander Didenko , Igor Buzevych , Alexander Gurbyk , Vitaliy Bekh

The black-striped pipefish Syngnathus abaster, which naturally inhabits brackish waters, invaded a variety of fresh waters of the Black Sea basin. Although this species penetrated fresh waters a long time ago and is known to prey on fish larvae, its habits and effects in these habitats were not studied sufficiently. The aim of this study was to investigate S. abaster predation on other fishes in invaded fresh waters in detail. The material for the study was collected between 2015 and 2020 in the Stugna River and Kaniv Reservoir (Dnieper River basin) during the breeding period of the majority of local fishes. The gut content analysis showed the presence of 44 prey taxa in the diet of S. abaster. The most important and frequently encountered prey were copepods. Fish larvae contributed 6.5–55.2 % of the total food items, while their relative importance in the diet ranged from 0.03 %IRI (percent index of relative importance) up to 14.36 % IRI. Four groups of fish prey were identified: Gobiidae, Cyprinidae, Perccottus glenii, and S. abaster juveniles. Fish were more frequently encountered and more abundant in the digestive tract of females than in males of S. abaster. Overall, the level of predation of this species on fish larvae was low and temporally associated with the massive spawning of co-occurring fishes inhabiting macrophytes. Previous studies suggest high to moderate probability of establishment of this species in the Laurentian Great Lakes if introduced, but the present study suggests relatively little effect on native fishes.

天然栖息在咸淡水域的黑条纹管鱼（Syngnathus abaster）入侵了黑海盆地的各种淡水。虽然这一物种很久以前就进入淡水，并以鱼类幼虫为食，但它的习性和对这些栖息地的影响并没有得到充分的研究。本研究的目的是详细地研究入侵淡水水域中沙鲈对其他鱼类的捕食行为。该研究的材料是在2015年至2020年期间在斯图格纳河和卡尼夫水库（第聂伯河流域）收集的，当时是大多数当地鱼类的繁殖期。肠道含量分析表明，沙蚕的饮食中存在44个猎物类群。最重要和最常遇到的猎物是桡足类。鱼苗占饵料总量的6.5 ~ 55.2%，其在饵料中的相对重要性在0.03% ~ 14.36%之间。捕获的鱼类有四大类：梭子鱼科、梭子鱼科、梭子鱼科和梭子鱼幼鱼。雌鱼的消化道比雄鱼的消化道更频繁、更丰富。总体而言，该物种对鱼类幼虫的捕食水平较低，并且与栖息于大型植物的共生鱼类的大量产卵有关。以前的研究表明，如果引进该物种，在劳伦森五大湖建立该物种的可能性很高或中等，但本研究表明对本地鱼类的影响相对较小。

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引用次数: 0

A temporal comparison of nearshore fish communities in Hamilton Harbour and the Bay of Quinte areas of concern (1988–2021) 1988-2021年汉密尔顿港和昆特湾近岸鱼类群落的时间比较

IF 2.4 3区环境科学与生态学 Q3 ENVIRONMENTAL SCIENCES

Journal of Great Lakes Research

Pub Date : 2025-05-31 DOI: 10.1016/j.jglr.2025.102609

Nicole A. Turner, Melanie V. Croft-White, Christine M. Boston, Jonathan D. Midwood

Lake Ontario and, in particular, areas across the western basin have been subjected to intense anthropogenic stressors. In response, Areas of Concern (AOC) were designated to aid in rehabilitation efforts to reduce nutrient loading and improve aquatic habitat. Here we use fish community metrics (e.g., Index of Biotic Integrity (IBI)) as well as species occurrence and catch modelling to compare trends in fish population condition over 30 years between Hamilton Harbour (HH) and the Bay of Quinte (BoQ). We found clear spatial differences within HH and limited evidence for improvement in nearshore fish populations. The few exceptions were declines in non-native species catch and richness and total offshore species catch, driven primarily by declines in common carp (Cyprinus carpio) and alewife (Alosa pseudoharengus). Similar declines in non-native species richness were evident in the BoQ, but IBI and fish population metrics, including proportion of piscivore biomass and native species catch and richness, were always greater in BoQ. In contrast, several metrics and species in HH showed recent declines (following 2012) that rolled back improvements observed in the early 2000 s. Such HH-specific changes suggest that local (e.g., ongoing anthropogenic disturbance, novel invasive species, and minimal changes in habitat supply) rather than regional factors are limiting recovery of the fish community.

安大略湖，特别是整个西部盆地地区受到强烈的人为压力。作为回应，指定了关注区域（AOC）来协助恢复工作，以减少营养负荷和改善水生生境。在这里，我们使用鱼类群落指标（例如，生物完整性指数（IBI））以及物种发生和捕捞模型来比较汉密尔顿港（HH）和昆特湾（BoQ）之间30年来鱼类种群状况的趋势。我们发现了明显的HH空间差异和有限的证据表明近岸鱼类种群的改善。少数例外是非本土物种捕获量和丰富度以及近海物种总捕获量的下降，这主要是由鲤鱼（Cyprinus carpio）和灰鲱（Alosa pseudoharengus）的下降造成的。非本地物种丰富度在BoQ也有明显的下降，但IBI和鱼类种群指标（包括鱼类生物量比例、本地物种捕捞量和丰富度）在BoQ都更大。相比之下，HH的几个指标和物种最近出现了下降（2012年之后），逆转了21世纪初观察到的改善。这种特定于hh的变化表明，限制鱼类群落恢复的是当地因素（例如，持续的人为干扰、新入侵物种和栖息地供应的微小变化），而不是区域因素。

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引用次数: 0

Recovery of urban Great Lakes beaches after lake-level rise: The roles of infrastructure, sand supply, and management activities 湖面上升后五大湖城市海滩的恢复：基础设施、沙源和管理活动的作用

IF 2.4 3区环境科学与生态学 Q3 ENVIRONMENTAL SCIENCES

Journal of Great Lakes Research

Pub Date : 2025-05-22 DOI: 10.1016/j.jglr.2025.102603

C.R. Mattheus

Managing beaches along urban waterfront corridors of the North American Great Lakes is challenging, as already complex lacustrine hydro-, littoral sand-supply, and coastal morphodynamics are impacted by shoreline and offshore infrastructure in ways not yet fully understood. This paper addresses the legacy controls of geomorphic developments and changes in sand volume within lakefront embayments, during high decadal base water-level conditions, on subsequent beach-recovery dynamics, during lake-level fall. Showcased are insights from annual topobathymetric assessments from 2021 through 2024, over which time Lake Michigan’s base water level fell by ∼ 1 m from its 2020 highstand. Data from ongoing geological monitoring activities were supplemented with federal datasets, which provided information on 2012–2020 sand volumetric changes across urban lakefront embayments with ∼ 1.5 m of lake-level rise. Beach geomorphic developments with 2020–2024 interannual lake-level fall are shown to have been influenced by the legacy of preceding morphodynamic and sand-sequestration patterns. Unlike the shared lake-level and storm histories, these parameters are beach-specific. While all Chicago beach shorelines retreated and experienced overwash into backshore regions during lake-level rise, shoreline advance and foredune re-establishment with lake-level fall have been influenced by preceding sand volumetric changes. This has implications for coastal managers, who must develop site-specific mitigation plans that take intrinsic controls of lakefront structures and time-varying sand-transport patterns on beach morphodynamics into account. The re-establishment of ecologically important foredune areas within urban beaches is of particular interest, given that the urban lakefront of Chicago has recently hosted nesting pairs of the endangered Great Lakes piping plover.

管理北美五大湖城市滨水走廊的海滩是一项挑战，因为已经复杂的湖泊水力、沿海沙源和海岸形态动力学受到海岸线和海上基础设施的影响，其影响方式尚未完全了解。本文讨论了在高年代际基础水位条件下，湖滨河口地貌发展和沙量变化的遗留控制因素，以及在湖泊水位下降期间随后的海滩恢复动力学。展示了从2021年到2024年的年度地形深度评估的见解，在此期间，密歇根湖的基础水位从2020年的高点下降了约1米。正在进行的地质监测活动的数据补充了联邦数据集，这些数据集提供了2012-2020年湖泊水位上升~ 1.5 m时城市湖滨河口沙粒体积变化的信息。研究表明，2020-2024年湖泊水位年际下降的海滩地貌发展受到先前形态动力学和沙封存模式的影响。与共享的湖泊水位和风暴历史不同，这些参数是特定于海滩的。虽然所有的芝加哥海滩岸线在湖平面上升期间都后退并经历过冲过，但随着湖平面下降，岸线的推进和前丘的重建都受到先前沙粒体积变化的影响。这对沿海管理人员有影响，他们必须制定特定地点的缓解计划，将湖滨结构的内在控制和海滩形态动力学上随时间变化的沙尘输送模式考虑在内。在城市海滩内重建具有重要生态意义的前沙丘区域是特别值得关注的，因为芝加哥的城市湖滨最近迎来了濒临灭绝的五大湖管鸻成对筑巢。

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引用次数: 0

Silent invaders of freshwater ecosystems: Unveiling the microplastic crisis threatening the world’s largest soda lake (Lake Van, Türkiye) 淡水生态系统的无声入侵者：揭示威胁世界上最大的苏打湖（lake Van, trkiye）的微塑料危机

IF 2.4 3区环境科学与生态学 Q3 ENVIRONMENTAL SCIENCES

Journal of Great Lakes Research

Pub Date : 2025-05-21 DOI: 10.1016/j.jglr.2025.102604

Münevver Oral Kaba , Mert Minaz , Cüneyt Kaya , Thibaut Jouy , Irmak Kurtul , Ülgen Aytan

This study aims to assess the status of microplastic (MP) pollution in Lake Van (Türkiye), a vital freshwater ecosystem with a unique ecological significance. The objectives were to determine MP abundance, size distribution, type and polymer composition, and potential ecological risks to fish species. Comprehensive sampling was conducted at eight stations for water, while three of these stations specifically focused on the gastrointestinal tracts of fish. The findings indicate a high prevalence of MPs, particularly in areas with significant human activity, such as station 1 at Sapur (mean ± SD 69.08 ± 22.3 MP/m³) and station 6 at Gevaş (72.41 ± 26.9 MP/m³). Fibers were dominant in both water and fish samples, with polyethylene terephthalate (PET) and polyacrylonitrile (PAN) being the most commonly identified polymers. This study highlights the occurrence of MPs in endemic and/or economically important fish species such as tarek (Alburnus tarichi) (mean 1.50–2.25 MP/indiv.), Van loach (Oxynoemacheilus ercisianus) (mean 0.55 MP/indiv.), lizard barbel (Barbus lacerta) (mean 0.57 MP/indiv.), and Levantine scraper (Capoeta damascina) (mean 1.00–1.75 MP/indiv.). These findings highlight the potential ecological risks posed by MP contamination for ecosystem, fish, and human health, and the urgent need for targeted mitigation strategies to reduce MP pollution. The study provides critical baseline data for understanding MP dynamics in Lake Van and contributes to the broader understanding of freshwater MP contamination on a global scale.

摘要本研究旨在评估凡湖（t rkiye）的微塑料污染状况，凡湖是一个重要的淡水生态系统，具有独特的生态意义。目的是确定MP丰度、大小分布、类型和聚合物组成以及对鱼类的潜在生态风险。在8个站点对水进行了全面采样，其中3个站点专门关注鱼类的胃肠道。结果表明，MPs的患病率很高，特别是在人类活动显著的地区，如萨布尔的1号站（平均±SD 69.08±22.3 MP/m3）和格瓦库的6号站（72.41±26.9 MP/m3）。纤维在水和鱼样品中都占主导地位，聚对苯二甲酸乙二醇酯（PET）和聚丙烯腈（PAN）是最常见的聚合物。本研究强调了MPs在一些特有和/或经济上重要的鱼类中的发生率，如大鳞鱼（Alburnus tarichi）（平均1.50-2.25 MP/个体）、凡泥鳅（Oxynoemacheilus ercisianus）（平均0.55 MP/个体）、刺蜥（Barbus lacerta）（平均0.57 MP/个体）和地中海刮刀（Capoeta damascina）（平均1.00-1.75 MP/个体）。这些发现强调了多聚污染物对生态系统、鱼类和人类健康构成的潜在生态风险，以及迫切需要有针对性的缓解策略来减少多聚污染物。该研究为了解Van湖的MP动态提供了关键的基线数据，并有助于在全球范围内更广泛地了解淡水MP污染。

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引用次数: 0

FM2-3: Editorial Board / Information for Authors FM2-3：编辑委员会/作者信息

IF 2.4 3区环境科学与生态学 Q3 ENVIRONMENTAL SCIENCES

Journal of Great Lakes Research

Pub Date : 2025-05-14 DOI: 10.1016/S0380-1330(25)00085-1

引用次数: 0

Microcystin persistence in Lake Erie foreshore sands 伊利湖滨沙中微囊藻毒素的持久性

IF 2.4 3区环境科学与生态学 Q3 ENVIRONMENTAL SCIENCES

Journal of Great Lakes Research

Pub Date : 2025-05-14 DOI: 10.1016/j.jglr.2025.102601

Garrett B. Moots, Daryl L. Moorhead, Chelsey E. Suffety, Kayla M. Kinzel, Daryl F. Dwyer, Von Sigler

Research into the persistence of microcystin (MC) in foreshore sands is limited. Lake water and foreshore sand samples were collected weekly from three swim coves at Maumee Bay Park Beach (OH) during the recreational swim season to assess the accumulation and persistence of MC in foreshore sands. Enzyme-linked-immunosorbent-assay (ELISA) analysis showed that 14 % of lake water samples exceeded the EPA no-contact threshold for MC in recreational waters (8 µg/L), with a maximum concentration of 17 µg/L occurring during a bloom event. Average MC concentrations in surface foreshore sands (4 µg/L porewater) were significantly higher, on average, than in deeper sands (2 µg/L porewater), while peak sand MC concentrations exceeded 29 µg/L during two bloom events. Overall, MC concentrations in both shallow and deep sand exceeded water MC concentrations in 56 % of samples, indicating accumulation of MC in foreshore sands. MC persistence was determined in laboratory microcosms containing either autoclaved or non-autoclaved sands augmented with MC. ELISA analysis showed a 46 % reduction in MC concentration in autoclaved sands over 7 weeks. In non-autoclaved sands, the MC concentration decreased by 100 % during the study, with approximately 99 % of the added MC degrading during days 21–28, suggesting that a biological mechanism drove degradation. Our findings reveal that beach sands can act as MC reservoirs, accumulating and concentrating MC during and following bloom events.

关于微囊藻毒素（MC）在前滨砂中的持久性研究有限。在休闲游泳季节，每周从莫米湾公园海滩（OH）的三个游泳海湾收集湖水和前滨沙样本，以评估MC在前滨沙中的积累和持久性。酶联免疫吸附法（ELISA）分析显示，14%的湖水样品超过了EPA在休闲水域的无接触阈值（8微克/升），在水华事件期间最高浓度为17微克/升。表层前滩砂（4µg/L孔隙水）的平均MC浓度显著高于深层砂（2µg/L孔隙水），而在两次水华事件中，峰值砂MC浓度超过29µg/L。总体而言，在56%的样品中，浅层和深层沙子中的MC浓度都超过了水中的MC浓度，表明MC在前滩沙子中积累。在实验室的微环境中，测定了MC的持久性，包括高压灭菌或非高压灭菌的含有MC的砂。ELISA分析显示，在7周内，高压灭菌砂中的MC浓度降低了46%。在非高压灭菌砂中，MC浓度在研究期间下降了100%，大约99%的添加MC在21-28天降解，这表明生物机制驱动了降解。我们的研究结果表明，在水华期间和之后，海滩砂可以作为MC储集层，聚集和集中MC。

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引用次数: 0

Lean lake trout are found in spawning condition during spring-summer in lakes Michigan and Huron 在密西根湖和休伦湖的春夏季，瘦湖鳟鱼处于产卵状态

IF 2.4 3区环境科学与生态学 Q3 ENVIRONMENTAL SCIENCES

Journal of Great Lakes Research

Pub Date : 2025-05-13 DOI: 10.1016/j.jglr.2025.102583

Shannon R. Cressman , Sarah A. Mansfield , Fredrick W. Goetz , Heather A. Hackney , Jared J. Homola , Francesco Guzzo , Charles R. Bronte

Here we report the first observations of the capture of lean lake trout (Salvelinus namaycush) in spawning condition in lakes Michigan and Huron during April–July, which is well outside their normal fall spawning season of September–December. Examination of 5731 lake trout landed by anglers at 56 ports in 2022 and 2023 revealed nine female lake trout possessing body cavities filled with mature, loose eggs and two males in ripe condition. Six fish were hatchery-reared and five were of wild origin. Ages of these fish ranged from 6 to 19 years and, of those where strain could be determined, were members of the Seneca Lake and Lewis Lake genetic strains. Loose eggs were similar in appearance to those found in mature fish in fall on spawning grounds. Histological examination of eggs from four females confirmed all were in some stage of ovarian maturity. Two females had ovulated just prior to capture, and the remaining two ovulated much earlier than the capture date. The adaptive advantage of the alternative seasonal spawning is speculative but may include reduced competition with fall spawners, decreased predation risk for juveniles during winter, and access to greater environmental resources in the early spring and summer.

在这里，我们报告了4 - 7月在密歇根湖和休伦湖产卵条件下捕获瘦湖鳟鱼（Salvelinus namaycush）的第一次观察，这远远超出了它们正常的秋季产卵季节9 - 12月。对2022年和2023年在56个港口钓到的5731条湖鳟鱼进行了检查，结果发现，9条雌性湖鳟鱼的体腔里充满了成熟、疏松的卵，2条雄性湖鳟鱼的体腔已经成熟。6条鱼是孵化场饲养的，5条是野生的。这些鱼的年龄从6岁到19岁不等，在那些可以确定菌株的鱼中，是塞内卡湖和刘易斯湖遗传菌株的成员。松散的卵在外观上与秋天在产卵地发现的成熟鱼相似。对4只雌鼠的卵细胞进行组织学检查，证实它们均处于卵巢成熟的某个阶段。两只雌性在捕获前刚刚排卵，其余两只在捕获日期之前排卵。替代性季节性产卵的适应性优势是推测性的，但可能包括减少与秋季产卵者的竞争，降低冬季幼鱼被捕食的风险，以及在早春和夏季获得更多的环境资源。

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引用次数: 0

Frequency and duration of weak thermal stratification and hypoxia in the shallow western basin of Lake Erie 伊利湖西部浅层盆地弱热分层和缺氧的频率和持续时间

IF 2.4 3区环境科学与生态学 Q3 ENVIRONMENTAL SCIENCES

Journal of Great Lakes Research

Pub Date : 2025-05-06 DOI: 10.1016/j.jglr.2025.102596

Yulong Kuai, Mathew G. Wells

Polymictic lakes are not always continuously mixed; they often experience alternating periods of mixing and weak stratification. The shallow western basin of Lake Erie is one example of a polymictic basin where the frequency of mixing has important consequences for water quality. In this study, we capture high-frequency data from the summers of 2021, 2022, and 2023, including water temperature, dissolved oxygen (DO), and water current velocity. This dataset allows us to show that hypoxic events (<2 mg/L) are triggered by episodes of weak stratification in Pigeon Bay, in western Lake Erie. Our five sampling sites in Pigeon Bay were located 50 m to 20 km from an important nearshore municipal water intake that supplies drinkable water to ∼66,800 residents and to the second largest greenhouse cluster in the world. Between June and September in these 3 years, we found that Pigeon Bay was stratified with a vertical temperature difference above 2 °C, for respectively 45 % (2021), 54 % (2022), and 25 % (2023) of the time. Significantly, all the hypoxic events were associated with stratified events. During the sampling periods, stratified events and hypoxic events were induced by either 1) local surface heating or 2) advection of hypolimnetic water from central Lake Erie. The majority of the hypoxic events in Pigeon Bay (83 % in 2021, 86 % in 2022, and 67 % in 2023) were associated with the horizontal transport of cold water that originated over 20 km from the central basin of Lake Erie.

多相湖泊并不总是连续混合；它们经常经历混合和弱分层交替的时期。伊利湖西部浅水盆地是多融盆地的一个例子，混合的频率对水质有重要影响。在本研究中，我们捕获了2021年、2022年和2023年夏季的高频数据，包括水温、溶解氧（DO）和水流速度。这个数据集可以让我们证明缺氧事件（2mg /L）是由伊利湖西部鸽子湾的弱分层引发的。我们在鸽湾的五个采样点距离一个重要的近岸市政取水口50米至20公里，该取水口为约66,800名居民和世界第二大温室群提供饮用水。在这3年的6 - 9月间，我们发现鸽湾垂直温差大于2°C的分层时间分别为45%（2021年）、54%（2022年）和25%（2023年）。值得注意的是，所有缺氧事件都与分层事件相关。在采样期间，分层事件和缺氧事件是由1)局部地表加热或2)伊利湖中部低通量水平流引起的。鸽子湾的大多数缺氧事件（2021年为83%，2022年为86%，2023年为67%）与来自伊利湖中央盆地20公里以上的冷水水平输送有关。

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引用次数: 0

Nursing Nile tilapia (Oreochromis niloticus) fry in cages improves growth performance, feed efficiency, condition factor, and growth pattern for stock enhancement 在网箱中饲养尼罗罗非鱼（Oreochromis niloticus）鱼苗可以提高生长性能、饲料效率、条件因子和生长模式，从而提高种群数量

IF 2.4 3区环境科学与生态学 Q3 ENVIRONMENTAL SCIENCES

Journal of Great Lakes Research

Pub Date : 2025-05-05 DOI: 10.1016/j.jglr.2025.102587

Omega Anthony Vicent , Edmond Alavaisha , Samwel Mchele Limbu

The contribution of Nile tilapia (Oreochromis niloticus) to food security and livelihoods around Lake Victoria is diminishing due to recruitment overfishing. However, the application of stock enhancement as an alternative management approach for recruitment-overexploited stocks in developing countries is limited by scanty information, particularly regarding a suitable nursing system. This study determined growth performance, feed utilization, survival, condition factor, and growth pattern of Nile tilapia fry nursed in tanks, hapas-in-pond, and lake-based cages in Lake Victoria. Phytoplankton composition, abundance, and diversity were also assessed across the systems. Each system was stocked with 250 fry (mean weight: 0.63 ± 0.12 g) in triplicate and fed a commercial diet for 10 weeks. Results showed that the fry nursed in cages had significantly higher final weight (FW: 22.5 ± 0.86 g), daily weight gain (DWG: 0.33 ± 0.01 g/day), and specific growth rate (SGR: 4.47 ± 0.05%/day) compared to those in hapas-in-pond (FW: 16.4 ± 0.23 g, DWG: 0.22 ± 0.01 g/day, SGR: 4.04 ± 0.01%/day) and tanks (FW: 9.38 ± 0.23 g, DWG: 0.12 ± 0.00 g/day, SGR: 3.27 ± 0.03%/day) nursing systems (p < 0.05). Moreover, the fry reared in cages had significantly higher relative condition factor (K_n: 1.50 ± 0.01) and lower feed conversion ratio (FCR: 1.24 ± 0.06) than those reared in hapas-in-pond (K_n: 1.26 ± 0.01 and FCR: 1.32 ± 0.02) and tanks (K_n: 1.15 ± 0.01 and FCR: 1.53 ± 0.02) (p < 0.05). Cage- and pond-based culture systems supported isometric growth of fry. Percentage survival did not differ significantly among culture systems (p > 0.05). Hapas-in-pond had significantly higher phytoplankton abundance (21.57 × 10⁴ cells/mL) than cages (5.53 × 10⁴) and tanks (2.76 × 10⁴) (p < 0.05). Conclusively, nursing Nile tilapia fry in cages improves growth and feed efficiency, offering a promising strategy for stock enhancement to manage overfished populations.

由于过度捕捞，尼罗罗非鱼（Oreochromis niloticus）对维多利亚湖周围粮食安全和生计的贡献正在减少。但是，由于缺乏资料，特别是关于适当的护理制度的资料，发展中国家将增加库存作为征聘过度开发的库存的另一种管理办法的应用受到限制。本研究测定了维多利亚湖尼罗罗非鱼苗种的生长性能、饲料利用率、成活率、条件因子和生长模式。对各系统的浮游植物组成、丰度和多样性也进行了评估。每个体系放生250尾鱼苗（平均体重0.63±0.12 g），每组3次，投喂商品饲料10周。结果表明：网箱育苗的末重（FW: 22.5±0.86 g）、日增重（DWG: 0.33±0.01 g/d）和特定生长率（SGR: 4.47±0.05%/d）显著高于池中育苗（FW: 16.4±0.23 g, DWG: 0.22±0.01 g/d, SGR: 4.04±0.01%/d）和池中育苗（FW: 9.38±0.23 g, DWG: 0.12±0.00 g/d, SGR: 3.27±0.03%/d） (p <；0.05)。网箱养殖的鱼苗相对条件因子（Kn: 1.50±0.01）显著高于池中养殖（Kn: 1.26±0.01,FCR: 1.32±0.02）和池中养殖（Kn: 1.15±0.01,FCR: 1.53±0.02），饵料系数（FCR: 1.24±0.06）显著低于网箱养殖(p <；0.05)。网箱和池塘培养系统支持鱼苗等长生长。不同培养系统的存活率无显著差异(p >；0.05)。池内hapas的浮游植物丰度（21.57 × 104细胞/mL）显著高于网箱（5.53 × 104细胞/mL）和水箱（2.76 × 104细胞/mL） (p <；0.05)。最后，在网箱中喂养尼罗罗非鱼苗可以提高生长和饲料效率，为增加种群数量以管理过度捕捞种群提供了一种有希望的策略。

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