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

Taxonomic diversity of bacterial communities in the sediments of a soda lake in Arusha, Tanzania 坦桑尼亚阿鲁沙苏打湖沉积物中细菌群落的分类多样性

IF 2.5 3区环境科学与生态学 Q3 ENVIRONMENTAL SCIENCES

Journal of Great Lakes Research

Pub Date : 2025-10-01 DOI: 10.1016/j.jglr.2025.102649

Sadikiel E. Kaale , Robert S. Machang’u , Thomas J. Lyimo

Soda lakes are special ecosystems with high salinity and alkalinity, notably found in the Great Rift Valley of East Africa. Given the unique nature of soda lakes, it is interesting and valuable to examine their bacterial composition as an initial step towards bioprospecting. This study provides the first metagenomic snapshots of bacterial communities inhabiting Lake Natron sediments using the 16S rRNA gene sequenced using a PacBio sequencing system. Results show high abundance and diversity of species in general, with notable dominance of Firmicutes, Bacteroidota, Actinomycetota, and Proteobacteria with the relative abundances of 45.21 %, 25.23 %, 12.59 %, and 23.29 %, respectively. At the class level, Bacteroidia (23.54 %), Gammaproteobacteria (22.32 %), Bacilli (19.66 %), and Clostridia (22.32 %) were the most dominant classes. At lower taxonomic ranks (especially at the genus and species levels), there was an increase in the percentage of unknown and “Candidate Phyla” species (i.e., those discovered using genetic methods but not yet fully characterized or classified), suggesting the potential presence of new bacterial taxa in Lake Natron. The diversity indices revealed a high level of community diversity, with a large number of species, the presence of rare species, and an even distribution of bacteria across the sampling points. Although this study provides the first report on the existence of different bacterial taxa in Lake Natron, additional investigation into the biotechnological importance of the found species is of importance; hence, a functional metagenomic study is advised.

苏打湖是一种特殊的高盐度和高碱度生态系统，主要分布在东非大裂谷。鉴于苏打湖的独特性质，研究其细菌组成作为生物勘探的第一步是有趣和有价值的。本研究利用PacBio测序系统对16S rRNA基因进行测序，提供了栖息在Natron湖沉积物中的细菌群落的第一个宏基因组快照。结果表明，总体上物种丰度和多样性较高，其中厚壁菌门、拟杆菌门、放线菌门和变形菌门优势显著，相对丰度分别为45.21%、25.23%、12.59%和23.29%。在纲水平上，Bacteroidia（23.54%）、Gammaproteobacteria（22.32%）、Bacilli（19.66%）和Clostridia（22.32%）为优势纲。在较低的分类等级（特别是属和种水平）上，未知和“候选门”物种（即使用遗传方法发现但尚未完全表征或分类的物种）的百分比有所增加，表明Natron湖可能存在新的细菌分类群。群落多样性指数显示群落多样性水平高，物种数量多，存在稀有物种，细菌在各采样点分布均匀。虽然本研究首次报道了纳特龙湖不同细菌分类群的存在，但对所发现物种的生物技术重要性的进一步研究具有重要意义；因此，建议进行功能宏基因组研究。

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引用次数: 0

Reproductive condition, oocyte maturation, and life history variation in Lake Superior burbot (Lota lota) 苏必利尔湖鳕（Lota Lota）的生殖状况、卵母细胞成熟和生活史变化

IF 2.5 3区环境科学与生态学 Q3 ENVIRONMENTAL SCIENCES

Journal of Great Lakes Research

Pub Date : 2025-10-01 DOI: 10.1016/j.jglr.2025.102661

Michael J. Woodworth, Jill B.K. Leonard

Burbot (Lota lota) are a cryophilic freshwater fish native to many cold-water systems in the Northern Hemisphere. Within the Laurentian Great Lakes, current fishing regulations and increasing popularity are leading to interest in population dynamics and the sustainability of current and future burbot populations. To understand population dynamics, it is important to better understand the reproductive ecology of burbot. Currently, little is known about the reproductive ecology and the variation within reproductive behavior of burbot. In this study, we evaluated the reproductive ecology of southern Lake Superior burbot by characterizing the timing of reproductively maturing adult burbot and assessing the final oocyte maturation process. Samples were collected during two sampling seasons, which spanned from December to April. Riverine-collected burbot had high proportions (>90 %) of reproductively maturing individuals matched with females in the final stages of oocyte development during a short (3–5 week) period. Alternatively, lacustrine-collected burbot had low proportions (24 %) of reproductively maturing individuals and low proportions of females within the final stages of oocyte development (16 %). Unlike riverine captures, lacustrine-captured individuals indicated a prolonged presence of reproductively maturing individuals that lasted from December to at least early April. These results suggest variation within the reproductive ecology of Lake Superior-residing burbot.

大闸鱼（Lota Lota）是一种嗜冷淡水鱼，原产于北半球的许多冷水系统。在劳伦森五大湖内，目前的捕鱼条例和日益普及使人们对种群动态和当前和未来的长须鲸种群的可持续性产生了兴趣。为了更好地了解种群动态，必须更好地了解burbot的生殖生态。目前，人们对burbot的生殖生态学和生殖行为的变化知之甚少。在这项研究中，我们通过表征成年burbot生殖成熟的时间和评估最终的卵母细胞成熟过程来评估南部苏必利尔湖burbot的生殖生态。样本是在12月至4月的两个采样季节收集的。在短（3-5周）的卵母细胞发育的最后阶段，河流采集的burbot有很高比例（> 90%）的生殖成熟个体与雌性配对。另外，湖采burbot的生殖成熟个体比例低（24%），卵母细胞发育最后阶段的雌性比例低（16%）。与河流捕获的个体不同，湖泊捕获的个体表明，从12月到至少4月初，生殖成熟个体的存在时间较长。这些结果表明苏必利尔湖栖息的白鱀鲸的生殖生态存在差异。

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引用次数: 0

Holocene freshwater microbialites of Lake Sevan (Armenia) 亚美尼亚塞万湖全新世淡水微生物岩

IF 2.5 3区环境科学与生态学 Q3 ENVIRONMENTAL SCIENCES

Journal of Great Lakes Research

Pub Date : 2025-10-01 DOI: 10.1016/j.jglr.2025.102647

Lilit Sahakyan , Claude Colombié , Anna Sukiasyan , Lusine Hambaryan , Taron Grigoryan , Torsten Haberzettl , Thomas Kasper , Zhanneta Stepanyan , Stella Mkrtchyan , Hayk Hovakimyan , Sebastien Joannin , Ara Avagyan

Combined onshore and offshore investigations reveal microbialites in Lake Sevan ranging from 1915 m a.s.l. (i.e., 15 m above modern lake level, 1–30 cm thick) to submerged structures (2–5 m wide, 0.4–1 m high) at 45 m water depth. These carbonate deposits exhibit diverse macrostructures such as domical, spherical, tabular, elliptical, planar, and pendant/lobate crusts and oncolites. Thin section and SEM analyses reveal thrombolite microstructures with clots and shrubs, stromatolites (columnar and planar), leiolites, and striated mesostructures. Various types of spherulites, peloids, filamentous structures, microborings, and well-preserved remains of cyanobacteria provide evidence of biological involvement in precipitation. Radiocarbon ages of microbialites range from 9060 ⁺¹⁹⁵/_-70 to 190 ⁺¹²⁵/_-190 cal BP, based on 10 samples from different locations. Some of these samples indicate periods of natural lake level fluctuations during their formation. Radiated aggregates of fibrous crystals, formed exclusively in the lake’s deep, low-temperature environments, were dated to 1510 ⁺¹⁶⁰/_-115 cal BP. Geochemical and EDX analyses reveal low-magnesium calcite as the primary precipitate, with secondary rhodochrosite (MnCO₃) on the surface of submerged samples. Microalgae communities in sand, silt, and water are dominated by Cyanophyta, Bacillariophyta, and Chlorophyta. Cyanobacteria such as Oscillatoria sp. and Anabaena sp. were detected both within microbialites and in the surrounding environments, demonstrating their long-standing presence in the lake. At 4.3 m water depth in Qanagegh, reduced carbonate content in sands is linked to local gas seepage. The abundant presence of cyanobacteria, particularly Oscillatoria limnetica, suggests a relationship between microbial growth and gas-driven geochemical conditions.

陆上和海上综合调查显示，塞万湖的微生物岩范围从1915 m a.s.l（即高于现代湖面15 m， 1-30 cm厚）到45 m水深的淹没结构（2-5 m宽，0.4-1 m高）。这些碳酸盐沉积物具有不同的宏观结构，如圆顶、球形、板状、椭圆形、平面、垂状/叶状结壳和肿瘤。薄片和扫描电镜分析显示血栓的微观结构有凝块和灌木、叠层石（柱状和平面）、平面岩和条纹细观结构。各种类型的球粒、似球粒、丝状结构、微孔和保存完好的蓝藻遗骸提供了生物参与降水的证据。微生物岩的放射性碳年龄在9060 +195/-70 ~ 190 +125/-190 cal BP之间。其中一些样品表明，在它们形成期间，湖泊水位有过自然波动。纤维晶体的辐射聚集体，仅形成于湖泊深处的低温环境中，其年代为1510 +160/-115 cal BP。地球化学和EDX分析显示，低镁方解石为原生沉淀，次生红锰矿（MnCO3）在浸没样品表面。沙、淤泥和水中微藻群落以蓝藻、硅藻和绿藻为主。在微生物岩和周围环境中都检测到蓝藻，如振荡藻和水藻，表明它们长期存在于湖中。在Qanagegh水深4.3 m处，砂岩中碳酸盐含量的降低与局部气体渗漏有关。蓝藻的大量存在，特别是石灰藻，表明微生物生长与气体驱动的地球化学条件之间存在关系。

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引用次数: 0

Bathymetric and contemporary sediment quantity assessment for the Lukanga Swamps in central Province, Zambia 赞比亚中部省Lukanga沼泽的水深和当代泥沙量评价

IF 2.5 3区环境科学与生态学 Q3 ENVIRONMENTAL SCIENCES

Journal of Great Lakes Research

Pub Date : 2025-10-01 DOI: 10.1016/j.jglr.2025.102646

Manoah Muchanga , Henry M. Sichingabula , Moses N. Chisola , Beauty S. Mbale , Gershom Pule , Rowen Jani , Fungai Musana

Globally, wetlands are under threat and Lukanga Swamps (14,000 km²), a wetland of international significance and a Ramsar site, is one of them. This study aimed to assess the bathymetry and sediment quantity of the Lukanga Swamps, identify associated threats, and compare sedimentation with similar wetland case studies. A Hydrographic Survey Boat Sonar Model RC-S2 mounted with a Trimble Hemisphere OmniSTAR Virtual Base Station for Differential Geographic Positioning System was used to measure water depths across Lukanga Swamps (here referred to as the Swamp). Data on sediment depth was collected using a sediment coring method with the aid of a Graduated Sediment Depth Rod. Bathymetric and sediment data were analysed using the Inverse Distance Weighted interpolation method in ArcMap 10.4 Environment. The findings showed that at the time of survey, the water stored in the Swamp was about 2918 million cubic metres (MCM), and about 1200 MCM of the Swamp’s capacity was lost to sedimentation. The study concludes that the Swamp has lost the original storage capacity and Nature-based Solutions are recommended to preserve it. Although other studies have been done on the Lukanga Swamps, we are of the view that this study is a novel contribution to the understanding of the Lukanga Swamps’ storage capacity and sedimentation dynamics by producing, for the first time, a comprehensive bathymetric map and sediment distribution map for the Swamp, which provide firsthand scientific baseline data that allows for future monitoring of the Swamp’s sedimentation rates and storage capacity over time.

在全球范围内，湿地正受到威胁，具有国际意义的湿地和拉姆萨尔湿地——Lukanga swamp（14000平方公里）就是其中之一。本研究旨在评估鲁康加沼泽的水深和沉积物数量，确定相关的威胁，并与类似的湿地案例进行比较。利用RC-S2型水文测量船声纳模型，安装了Trimble半球OmniSTAR差分地理定位系统虚拟基站，对陆坎加沼泽（此处简称沼泽）进行了水深测量。沉积物深度数据的采集采用了沉积物取心法，并借助分级沉积物深度杆。利用arcmap10.4环境中的逆距离加权插值方法对水深和沉积物数据进行分析。调查结果显示，在调查时，沼泽的储水量约为2.918亿立方米，其中约1200亿立方米的沼泽容量因沉积而损失。该研究的结论是，沼泽已经失去了原有的储存能力，建议采用基于自然的解决方案来保护它。虽然已有其他研究对陆坎加沼泽进行了研究，但我们认为，本研究首次绘制了陆坎加沼泽的综合水深图和沉积物分布图，为今后监测陆坎加沼泽的沉积速率和储存能力提供了第一手的科学基线数据，对了解陆坎加沼泽的储存能力和沉积动力学做出了新的贡献。

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引用次数: 0

Phases of anthropogenic activities since the mid-20th century from the sediment geochemistry of Laguna de Bai (Philippines) 从菲律宾拉古纳德白（Laguna de Bai）沉积物地球化学特征看20世纪中期以来的人类活动阶段

IF 2.5 3区环境科学与生态学 Q3 ENVIRONMENTAL SCIENCES

Journal of Great Lakes Research

Pub Date : 2025-10-01 DOI: 10.1016/j.jglr.2025.102635

Chris Carl Agustin V. Toyado , Caroline Marie B. Jaraula

Metro Manila, the Philippines’ capital region, industrialized relatively recently in the mid-20th century following a long period of colonial occupation and pre-colonial settlement. Laguna de Bai (LdB) flanks the coasts of Metro Manila, and its sediments record the onset and evolution of industrialization in the country. Understanding the evolution of anthropogenic impact on LdB will direct its long-term management policies better. Major/trace element and grain size records in a sediment core from Laguna de Bai’s Western Lobe basin were examined for markers of this industrialization, and two phases of anthropogenic impact were identified: Land Reorganization and Increased Pollution. We found that the start of Phase 1 is synchronous with increased anthropogenic impact in other Southeast Asian and global records and provides a Southeast Asian perspective to the timing and records of anthropogenic activities in the geologic record. In Phase 1, Land Reorganization (CE 1953–1967) is indicated by major terrigenous elements Al, Ti, and Fe, which rapidly increased to 1.36 × Freshwater Baseline levels likely due to increased sediment generation associated with World War II recovery-, population-, and urbanization-driven changes in land use. This increased sedimentation shoaled the basin, ventilating its bottom waters. This is seen in redox-sensitive elements as an enrichment in Mn and a depletion of Mo relative to U. The additional sediment generated increased water column turbidity and reduced primary production. These changes were maintained in Phase 2, Increased Pollution (CE 1967–1998), with increased Pb pollution possibly from petrol use.

马尼拉大都会是菲律宾的首都地区，在经历了长时间的殖民占领和殖民前定居之后，在20世纪中期相对较晚才开始工业化。拉古纳德拜（LdB）位于马尼拉大都会海岸两侧，其沉积物记录了该国工业化的开始和演变。了解人类活动对低开发银行影响的演变将更好地指导其长期管理政策。研究了拉古纳德白西叶盆地沉积物岩心的主要/微量元素和粒度记录，以寻找工业化的标志，并确定了人类活动影响的两个阶段：土地重组和污染加剧。我们发现，第1阶段的开始与其他东南亚和全球记录中人类活动影响的增加是同步的，这为地质记录中人类活动的时间和记录提供了东南亚的视角。在第一阶段，土地重组（CE 1953-1967）以主要的陆源元素Al、Ti和Fe为标志，其含量迅速增加到淡水基线水平的1.36倍，这可能是由于与第二次世界大战恢复、人口和城市化驱动的土地利用变化相关的沉积物生成增加。这种增加的沉降使盆地变浅，使其底部的水通风。这在氧化还原敏感元素中表现为Mn的富集和Mo相对于u的消耗。额外的沉积物增加了水柱浊度，减少了初级产量。这些变化在第2阶段“污染增加”（ce1967 - 1998）中保持不变，铅污染可能因使用汽油而增加。

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引用次数: 0

Temporal patterns of young-of-year fish emigration in Upper St. Lawrence River coastal wetlands in relation to environmental change 上圣劳伦斯河滨海湿地幼鱼洄游的时间格局与环境变化的关系

IF 2.5 3区环境科学与生态学 Q3 ENVIRONMENTAL SCIENCES

Journal of Great Lakes Research

Pub Date : 2025-10-01 DOI: 10.1016/j.jglr.2025.102651

Thornton A. Ritz, John M. Farrell

Young-of-year (YOY) fish emigration from shallow coastal wetlands to deeper embayments via connectivity channels represents a critical life history milestone. Emigration is typified by growth, dispersal, and changes in nursery habitat that influence species differently based on abiotic tolerance. To test this, we conducted a field study examining the relationships between YOY fish emigration and abiotic conditions in two freshwater coastal wetlands dominated by hybrid cattail Typha x glauca (Typha). Water level (WL), water temperature (WT), and dissolved oxygen concentration (DO) were monitored in these sites and temporally coupled with 42 consecutive days of YOY fish emigration. Individuals from five taxonomic groups emigrated over multiple time periods for a total catch of 25,272 YOY fish. Daily capture data was modeled with a Generalized Linear Model (GLM) to examine the influence of mean daily WL, mean daily WT, and mean daily DO on YOY fish emigration. Emigration patterns were variable for each taxonomic group and linked to known abiotic tolerance. Models of daily catch and environmental covariates indicated that increasing WL, WT, and decreasing DO had a significant effect on emigration. Typha dominance and reduced open water habitat likely influenced WT and hypoxia and may provide an advantage for tolerant protracted emigrants like largemouth bass (Micropterus salmoides) and brown bullhead (Ameiurus nebulosus). More sensitive groups like Leuciscidae (formally Cyprinidae), Lepomis, and smallmouth bass (Micropterus dolomieu) emigrated over truncated periods dependent on abiotic conditions. These findings highlight the role of fish tolerance and abiotic conditions during seasonal YOY fish emigration from USLR coastal wetlands.

鱼类通过连通通道从浅海湿地向深海湿地迁移是一个重要的生命史里程碑。迁移的典型特征是生长、扩散和苗圃栖息地的变化，这些变化基于非生物耐受性对物种的影响不同。为了验证这一点，我们对两个以杂交香蒲Typha x glauca （Typha）为主的淡水滨海湿地进行了实地研究，研究了YOY鱼洄游与非生物条件的关系。对这些地点的水位（WL）、水温（WT）和溶解氧浓度（DO）进行了监测，并与连续42天的鱼类洄游进行了时间耦合。来自五个分类群的个体在多个时期内迁移，每年总捕获量为25,272条鱼。采用广义线性模型（GLM）对日捕获数据进行建模，以检验平均日WL、平均日WT和平均日DO对鱼类年洄游的影响。每个分类群体的迁移模式是可变的，并与已知的非生物耐受性有关。日渔获量和环境协变量模型表明，增加WL、WT和减少DO对迁移有显著影响。Typha的优势和开阔水域栖息地的减少可能会影响WT和缺氧，并可能为大口黑鲈（Micropterus salmoides）和棕色牛头鱼（Ameiurus nebulosus）等耐受长期迁移的物种提供优势。更敏感的群体，如琵琶鱼科（正式的鲤科）、Lepomis和小嘴鲈鱼（Micropterus dolomieu），依靠非生物条件在短时间内迁移。这些发现强调了鱼类耐受性和非生物条件在鱼类从USLR沿海湿地季节性洄游中的作用。

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引用次数: 0

Evaluation of a recovering lake trout population in Lake Champlain using close-kin mark-recapture and genetic strain assignment 用近亲缘标记重捕和遗传品系分配评价尚普兰湖鳟鱼恢复种群

IF 2.5 3区环境科学与生态学 Q3 ENVIRONMENTAL SCIENCES

Journal of Great Lakes Research

Pub Date : 2025-10-01 DOI: 10.1016/j.jglr.2025.102623

Benjamin Marcy-Quay , Bernie Pientka , J. Ellen Marsden

Lake trout (Salvelinus namaycush) populations in many northern North American large lake systems have been substantially reduced or extirpated due to overfishing, habitat loss, and introduction of invasive species. Following reductions in fishing pressure and successful suppression of sea lamprey, attempts have been made to restore self-sustaining populations into most of these waters but success has been slow and limited. In contrast, lake-wide lake trout restoration occurred abruptly and rapidly in Lake Champlain after 40 years of stocking, with robust, widespread, and sustained wild recruitment observed from the 2012 cohort onwards. We sought to better understand the dynamics of the recovery success in Lake Champlain using a multi-year tissue dataset, in combination with a recently-designed genotyping panel and close-kin mark-recapture, to quantify the performance (i.e., survival and reproductive success) of stocking sources and strategies with an eye towards informing restoration programs in other systems. We also assessed the overall abundance of adult fish and parental dynamics associated with wild recruitment. Our results indicate that adult survival is remarkably high and overall abundance is low compared to other large lake systems in similar latitudes, with the vast majority of wild recruitment genetically traceable to the Seneca strain fish historically stocked by New York State. We observed little evidence of hybridization between the two strains and close-kin mark-recapture estimates indicated that approximately 20 % of the adult population was contributing to successful recruitment on a regular basis. Ultimately, our results point to a growing wild population that has the potential to become self-sustaining.

由于过度捕捞、栖息地丧失和入侵物种的引入，北美北部许多大型湖泊系统中的湖鳟（Salvelinus namaycush）种群已经大大减少或灭绝。随着捕捞压力的减少和对海七鳃鳗的成功捕杀，人们试图在这些水域中的大多数恢复自我维持的种群，但成功缓慢而有限。相比之下，经过40年的放养，尚普兰湖湖鳟鱼的恢复是突然而迅速的，从2012年开始观察到野生鳟鱼的强劲、广泛和持续的恢复。为了更好地了解尚普兰湖恢复成功的动态，我们使用了多年的组织数据集，结合最近设计的基因分型面板和近亲属标记再捕获，量化了放养来源和策略的表现（即生存和繁殖成功），以期为其他系统的恢复计划提供信息。我们还评估了成鱼的总体丰度和与野生招募相关的亲代动态。我们的研究结果表明，与类似纬度的其他大型湖泊系统相比，成鱼的存活率非常高，总体丰度较低，绝大多数野生招募的鱼在遗传上可追溯到纽约州历史上放养的塞内卡鱼种。我们观察到两种菌株之间几乎没有杂交的证据，近亲缘标记重新捕获估计表明，大约20%的成年人群定期成功招募。最终，我们的研究结果表明，越来越多的野生种群具有自我维持的潜力。

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引用次数: 0

Asynchrony within trophic levels maintains community stability over millennial-scale climate changes in a high-altitude lake 在千年尺度的气候变化中，高海拔湖泊营养水平的不同步维持了群落的稳定

IF 2.5 3区环境科学与生态学 Q3 ENVIRONMENTAL SCIENCES

Journal of Great Lakes Research

Pub Date : 2025-10-01 DOI: 10.1016/j.jglr.2025.102657

Yi Li , Hanxiao Zhang , Shouliang Huo

This study provides new insights into how climate change affects long-term ecosystem stability in high-altitude lakes, which are particularly vulnerable due to their simplified food webs and heightened environmental sensitivity. Despite their ecological importance, the long-term mechanisms through which multitrophic interactions govern ecosystem stability in these fragile systems remain poorly understood. In this study, we reconstruct over 1200 years of community succession in Lake Ngoring on the Qinghai–Tibet Plateau using sedimentary eDNA to elucidate these dynamics. Multivariate analyses revealed temperature as the dominant driver of community turnover (Mantel r = 0.58, P < 0.001), with warm periods fostering enhanced mutualistic networks between algae and decomposers. Network topology metrics demonstrated that while warming reduced overall cross-trophic interaction strength, it maintained robust cooperative linkages within trophic levels. Structural equation modeling further showed that climate-mediated species interactions significantly influenced ecosystem stability (path coefficient = 0.35), with intratrophic asynchrony emerging as a critical stabilizing mechanism (path coefficient = 0.20) that buffers climate impacts. Our findings provide novel insights into the resilience of high-altitude lake ecosystems, emphasizing the fundamental role of within-trophic-level dynamics in maintaining long-term ecological stability under climate change.

这项研究为气候变化如何影响高海拔湖泊的长期生态系统稳定性提供了新的见解，这些湖泊由于其简化的食物网和高度的环境敏感性而特别脆弱。尽管它们具有重要的生态意义，但在这些脆弱的系统中，多营养相互作用控制生态系统稳定性的长期机制仍然知之甚少。多变量分析显示，温度是群落更替的主要驱动因素（Mantel r = 0.58, P < 0.001），温暖时期促进了藻类和分解者之间的互惠网络的增强。网络拓扑指标表明，虽然变暖降低了整体的跨营养相互作用强度，但在营养水平上保持了强大的合作联系。结构方程模型进一步表明，气候介导的物种相互作用显著影响生态系统的稳定性（通径系数= 0.35），而萎缩内非同步是缓冲气候影响的关键稳定机制（通径系数= 0.20）。我们的研究结果为高海拔湖泊生态系统的恢复力提供了新的见解，强调了在气候变化下维持长期生态稳定的营养水平动态的基本作用。

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引用次数: 0

The benthic community of Lake Superior: Analysis of spatial and temporal trends from 1973 to 2022 苏必利尔湖底栖生物群落：1973 - 2022年时空趋势分析

IF 2.5 3区环境科学与生态学 Q3 ENVIRONMENTAL SCIENCES

Journal of Great Lakes Research

Pub Date : 2025-10-01 DOI: 10.1016/j.jglr.2025.102624

Lyubov E. Burlakova , Alexander Y. Karatayev , Olesia N. Makhutova , Susan E. Daniel , Jill Scharold , Anne E. Scofield , Elizabeth K. Hinchey

Biotic interactions and environmental changes due to increasing water temperatures, nutrient enrichment, and other factors can affect species diversity, abundance, and distribution. Lake Superior is the deepest and one of the most oligotrophic lakes in the Laurentian Great Lakes system. While considered the least affected by cultural eutrophication, Lake Superior is among the world’s fastest-warming freshwater bodies, having already exhibited resulting physical and ecological changes over the past three decades. We used data from current and historical surveys to identify spatial patterns and provide an assessment of the status and temporal trends of the Lake Superior benthic community over the last 50 years. Our study indicated that the dominance structure of the community remained quite stable, with the highest proportion of community comprised by the deepwater amphipod Diporeia hoyi, followed by Oligochaeta, Sphaeriidae, and Chironomidae. Benthic community structure differed spatially, with higher species diversity found in the shallow zone (≤30 m), the highest Diporeia densities at intermediate depth zones (30–50 and 50–90 m), and the lowest densities of all taxa in the deepest zone (>90 m). Lakewide benthos densities increased in the 1990s–2000s, most likely due to reduced fish predation, but are now stabilized. Although current benthos densities are still higher than in the 1970s, nearshore surveys indicated declines in Diporeia and other major taxa in the last decade. These changes may indicate a return to levels observed in the 1970s or reflect a long-term trend of decline in populations, reinforcing the importance of frequent monitoring that could foretell lakewide changes.

由于水温升高、营养物质富集等因素，生物相互作用和环境变化会影响物种的多样性、丰度和分布。苏必利尔湖是劳伦森五大湖系统中最深、最贫瘠的湖泊之一。虽然苏必利尔湖被认为是受文化富营养化影响最小的湖泊，但它是世界上变暖最快的淡水水体之一，在过去的30年里，它已经表现出了由此导致的物理和生态变化。我们利用当前和历史调查的数据来确定苏必利尔湖底栖生物群落的空间格局，并对过去50年的现状和时间趋势进行了评估。研究表明，该群落的优势结构较为稳定，深水片足类Diporeia hoyi所占比例最高，其次为Oligochaeta、Sphaeriidae和Chironomidae。底栖生物群落结构存在空间差异，浅层（≤30 m）的物种多样性较高，中间深度（30 - 50 m和50-90 m）的双poreia密度最高，而所有分类群的密度最低的是最深的（>90 m）。整个湖泊的底栖生物密度在20世纪90年代至21世纪初有所增加，很可能是由于鱼类捕食减少，但现在已经稳定下来。虽然目前底栖动物的密度仍然高于20世纪70年代，但近岸调查表明，在过去十年中，双足纲和其他主要分类群的密度有所下降。这些变化可能表明回归到1970年代所观察到的水平，或反映了种群数量下降的长期趋势，从而加强了频繁监测的重要性，这种监测可以预测整个湖的变化。

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引用次数: 0

Substrate mapping along a wave-dominated, sand-limited Great Lakes littoral zone: A case study from the bluff coast of Illinois, Lake Michigan 沿着波浪主导、沙质有限的五大湖沿岸地区绘制基底图：以伊利诺斯州、密歇根湖的悬崖海岸为例

IF 2.5 3区环境科学与生态学 Q3 ENVIRONMENTAL SCIENCES

Journal of Great Lakes Research

Pub Date : 2025-10-01 DOI: 10.1016/j.jglr.2025.102619

C. Robin Mattheus

While detailed geological maps are foundational to aquatic habitat classifications, few efforts have been made to generate these at regional scales along the highly dynamic coastal margins of the North American Great Lakes, where meter-scale fluctuations in water level, storms, and ice-related dynamics induce shoreline and shallow nearshore geomorphic changes. Variances in substrate type, over time, are enhanced in sand-limited settings, where clay-till and other glacial materials, grave-cobble lag deposits, and bedrock outcrops are common. A baseline understanding of sand distributions along these coasts is foundational to ecological and geomorphological inquiries. This paper describes an effort to leverage an offshore geological sample database to map the lake-bottom geology along the bluff coast of Illinois, where littoral sand is scarce and its distribution important to constrain from a coastal management perspective. Offshore geological sample information was integrated with high-resolution federal LiDAR, multi-beam sonar, and backscatter datasets, which provided the means of substrate-unit delineation. Distinction of sand versus non-sandy substrates was reflected in lake-bottom rugosity, backscatter intensity, and sample information. While a sandy lake bottom is smooth, nearshore terrains of greater textural and physiographic heterogeneity relate to craggy bedrock outcrops or a variety of undifferentiated sedimentary deposits, inclusive of gravel-cobble lags and scoured mud-rich till. A tripartite unit division of (1) sand, (2) undifferentiated sediments, and (3) bedrock holds broader application potential to sand-limited nearshore regions of the Great Lakes. Understanding the linkages between lake-bottom geomorphology and geological composition is useful to resiliency planning. Geological monitoring efforts benefit from such regional assessments.

虽然详细的地质图是水生生境分类的基础，但在北美五大湖高度动态的沿海边缘地区，很少有人努力在区域尺度上生成这些地质图，在那里，水位的米尺度波动、风暴和与冰有关的动态会引起海岸线和浅海近岸地貌的变化。随着时间的推移，在沙有限的环境中，基岩类型的差异会增加，在那里，粘土和其他冰川物质、坟墓卵石滞后沉积物和基岩露头是常见的。对这些海岸的沙子分布的基本了解是生态学和地貌学研究的基础。本文描述了利用海上地质样本数据库绘制伊利诺伊州悬崖海岸湖底地质地图的努力，那里的沿海沙子稀缺，从沿海管理的角度来看，其分布对限制很重要。海上地质样本信息与高分辨率联邦激光雷达、多波束声纳和后向散射数据集相结合，提供了基板单元圈定的手段。砂质与非砂质基质的区别反映在湖底粗糙度、后向散射强度和样本信息上。砂质湖底是光滑的，而近岸地形具有更大的纹理和地理异质性，与崎岖的基岩露头或各种未分异的沉积矿床有关，包括砾石-鹅卵石岩块和冲刷过的富含泥浆的坡地。由(1)砂、(2)未分异沉积物和(3)基岩组成的三部分单元划分，在五大湖的近岸地区具有更广泛的应用潜力。了解湖底地貌和地质组成之间的联系有助于进行弹性规划。地质监测工作受益于这种区域评估。

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引用次数: 0