IF 2 4区环境科学与生态学 Q2 LIMNOLOGY

Limnologica

Pub Date : 2026-03-01 Epub Date: 2026-01-28 DOI: 10.1016/j.limno.2026.126311

Kelsey A. Wilbanks , Darold P. Batzer

Growing water demands and climate change are altering the timing and magnitude of streamflows. To further understand streamflow changes over time, we assessed long-term streamflow trends for 33 basins in the South Atlantic-Gulf Drainage, southeastern United States. We gathered daily streamflow data and calculated the annual (1957 – 2022) mean, minimum and maximum of streamflows (m³/s; n = 373 gages). We used Mann-Kendall to indicate significant changes and Sen’s slope to indicate the magnitude of changes and averaged them for the 33 basins. Our results indicated that mean annual streamflows were increasing in the western and southern regions (24.2 % of basins) but decreasing in the larger central region (69.7 % of basins). Minimum streamflows indicated a large percentage of significant declines (34.0 % of gages) whereas maximum streamflows indicated a larger magnitude of declines (– 0.30 ± 1.7 (m³/s)/year). To further understand where streamflows were changing we assessed the relationship between streamflows and static spatial indicators including drainage area, elevation and ecoregions. To understand why streamflows were changing we assessed long-term trends for total precipitation, maximum and minimum temperatures, population and groundwater level. Using regression analysis and AIC model selection, we found that total precipitation explained 17 % of streamflow variation and drainage area explained 14 %. Temperatures and population increased across the region but were not related to variation in streamflow changes. Understanding the contributions of different drivers of streamflow changes provides insight for predicting water quantity changes, which affect water quality, ecological relationships and biodiversity.

不断增长的用水需求和气候变化正在改变河流的时间和规模。为了进一步了解流量随时间的变化，我们评估了美国东南部南大西洋-海湾流域33个盆地的长期流量趋势。我们收集了每天的流量数据，并计算了每年（1957 - 2022）的平均、最小和最大流量（m3/s; n = 373个量程）。我们用Mann-Kendall表示显著变化，用Sen’s slope表示变化幅度，并对33个流域进行平均。结果表明，西部和南部地区（24.2% %）的年平均流量呈增加趋势，而中部地区（69.7% %）的年平均流量呈减少趋势。最小流量的显著下降比例较大（34.0 %），而最大流量的显著下降幅度较大（- 0.30 ± 1.7 (m3/s)/年）。为了进一步了解河流的变化，我们评估了河流流量与静态空间指标（包括流域面积、高程和生态区）之间的关系。为了理解水流变化的原因，我们评估了总降水量、最高和最低温度、人口和地下水位的长期趋势。通过回归分析和AIC模型选择，发现总降水量对径流变化的解释率为17. %，流域面积对径流变化的解释率为14. %。整个区域的温度和种群数量均有所增加，但与河流流量变化无关。了解不同驱动因素对河流流量变化的贡献，有助于预测水量变化，从而影响水质、生态关系和生物多样性。

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引用次数: 0

Chironomid larvae bioturbation accelerates sediment carbon release and greenhouse gas emissions in macrophyte-dominated and algae-dominated shallow lakes 在以大型植物和藻类为主的浅水湖泊中，拟鱼幼虫的生物扰动加速了沉积物碳释放和温室气体排放

IF 2 4区环境科学与生态学 Q2 LIMNOLOGY

Limnologica

Pub Date : 2026-03-01 Epub Date: 2026-02-08 DOI: 10.1016/j.limno.2026.126320

Mengyu Sun , Mingjie Li , Ying Zhang , Yaling Su , Wenming Yan , Di Xu , Chengpeng Lu , Kuanyi Li , You Zhang

Aquatic eutrophication induces lake regime shifts, shifting sediment organic matter sources from macrophytes to algae, altering sediment-water interface (SWI) physicochemical properties and driving benthic macroinvertebrate communities toward pollution-tolerant taxa. Chironomid larvae, as a widespread pollution-tolerant benthic taxon, can influence sediment carbon mineralization and greenhouse gas (GHG) emission through bioturbation at the SWI. However, how different lake systems respond to benthic bioturbation remains unclear. This study, based on a 21-day microcosm experiment, investigated the impact of Propsilocerus akamusi bioturbation on SWI characteristics and GHG emissions in algae-dominated (ADS) and macrophyte-dominated (MDS) systems. ADS sediments exhibited lower organic matter and moisture content than MDS. Chironomid bioturbation enhanced sediment carbon mobilization and transformation, reduced SWI dissolved oxygen, and redistributed C, N, and P. The CO₂ fluxes in bioturbated MDS increased 1.25 × compared to untreated MDS controls and 1.12 × compared to bioturbated ADS. For CH₄ fluxes, in bioturbated ADS were 2.64 × higher than ADS controls, but 0.65 × lower than bioturbated MDS. Interactions between the macrophyte-to-algae trophic regime shift and chironomid bioturbation accelerated organic matter mineralization, likely diminishing carbon sequestration potential and amplifying carbon efflux in shallow lakes.

水体富营养化导致湖泊状态变化，将沉积物有机质来源从大型植物转移到藻类，改变沉积物-水界面（SWI）的物理化学性质，并推动底栖大型无脊椎动物群落向耐污染分类群发展。摇尾螺幼虫是一种广泛存在的耐污染底栖生物分类单元，通过生物扰动影响SWI沉积物碳矿化和温室气体排放。然而，不同的湖泊系统对底栖生物扰动的反应尚不清楚。本研究通过21天的微观环境实验，研究了赤色拟虾（prosilocerus akamusi）生物扰动对藻类为主（ADS）和大型植物为主（MDS）系统SWI特征和温室气体排放的影响。ADS沉积物有机质和水分含量低于MDS。手拟体生物扰动增强了沉积物碳的动员和转化，降低了SWI溶解氧，并重新分配了C、N和p。与未处理的MDS相比，生物扰动MDS中CO2通量增加了1.25 × ，与生物扰动ADS相比增加了1.12 × ，CH4通量比ADS对照组高2.64 × ，比生物扰动MDS低0.65 × 。大型植物向藻类的营养体制转变和chironomid生物扰动之间的相互作用加速了有机质矿化，可能降低了浅湖的碳固存潜力并放大了碳外排。

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引用次数: 0

Consumption of suspended microflora by rotifers and tardigrades in glacier cryoconite holes. 冰川冰孔中轮虫和缓步动物对悬浮菌群的消耗。

IF 2 4区环境科学与生态学 Q2 LIMNOLOGY

Limnologica

Pub Date : 2026-03-01 Epub Date: 2026-01-24 DOI: 10.1016/j.limno.2026.126312

Miloslav Devetter , Magdalena Střítecká , Ludmila H. Houfková , Michala Tůmová

The glacial cryoconite holes are a unique environment inhabited by a community of metazoans, mainly rotifers and tardigrades. They are metazoan consumers of microflora that live at temperatures never exceeding 0–1°C. Using fluorescently labeled, polystyrene beads of bacterial size (0.5 µm diameter) and epifluorescence microscopy, we estimated the filtration activity and clearance rate of glacier populations of rotifers and tardigrades and compared their relative effect on suspended food in cryoconite holes on two glaciers with different load of nutrients. The uptake of particles by both metazoan groups was important. The mean clearance rate calculated for feeding rotifers was similar at the two glaciers, 0.33 and 0.36 µl ind⁻¹ h⁻¹ for the glacier with lower and higher load of nutrients, respectively. The clearance rate of feeding tardigrades on the glacier with lower load of nutrients was 0.69 µl ind⁻¹ h⁻¹ and significantly differ from the glacier with higher load of nutrients,0.15 µl ind⁻¹ h⁻¹. The community of both groups cleared less than 1 % of the cryoconite hole volume per day, resulting in a minor impact. This is the first study to quantitatively estimate the feeding rate in tardigrades.

冰孔是一个独特的环境，主要是轮虫和缓步动物的后生动物群落。它们是生活在温度从不超过0-1°C的微生物群的后生动物。利用荧光标记的细菌大小的聚苯乙烯球（0.5 µm直径）和荧光显微镜，我们估计了冰川种群的轮虫和缓步动物的过滤活性和清除率，并比较了它们对两个不同营养负荷冰川冰孔中悬浮物的相对影响。两个后生动物群对颗粒的吸收都很重要。两个冰川上轮虫的平均清除率相似，在营养物质负荷较低和较高的冰川上分别为0.33和0.36 µl ind - 1 h - 1。低营养负荷冰川的食水熊虫清除率为0.69 µl ind−1 h−1，与高营养负荷冰川的0.15 µl ind−1 h−1差异显著。两组社区每天清除的低温孔体积都不到1% %，影响较小。这是第一次定量估计缓步动物摄食率的研究。

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引用次数: 0

Development of benthic macroinvertebrates-based multimetric index for assessing the ecological health of Ethiopian Highland streams 基于底栖大型无脊椎动物的埃塞俄比亚高原河流生态健康评价多指标的建立

IF 2 4区环境科学与生态学 Q2 LIMNOLOGY

Limnologica

Pub Date : 2026-03-01 Epub Date: 2026-02-18 DOI: 10.1016/j.limno.2026.126321

Yared Worku , Mengistu Asmamaw , Argaw Ambelu

Headwater streams in Ethiopia’s highlands are essential but increasingly threatened by human activities and environmental pressures. Effective conservation requires robust indices to assess ecological health. This study developed a macroinvertebrate-based multimetric index (MMI) for streams in the Dinki watershed, central Ethiopia. From 37 potential metrics, five core metrics were selected: percentage of Ephemeroptera-Odonata-Trichoptera (%EOT), percentage of Trichoptera (%Trico), Hemiptera abundance, Family Biotic Index (FBI), and Average Score Per Taxon (ASPT), based on their response to disturbances, Mann-Whitney U test, Spearman correlation, and boxplots. The MMI was calculated using the minimum and maximum sum scores of core metrics across impacted and reference sites. The lowest score (10.22), indicating poor health, occurred at most Dinki, Zego, and Dense sites, while the highest (22.43), indicating very good health, occurred at Gedamoch and selected Zego and Dense sites. Based on a potential range of 5–25, sites were classified into five ecological health categories. Validation using Spearman’s rs, RDA, boxplots, and Mann-Whitney U tests confirmed that both the core metrics and MMI effectively distinguish impacted from reference sites, highlighting its value as a practical tool for rapid ecological assessment of Ethiopian highland streams.

埃塞俄比亚高地的水源溪流是必不可少的，但日益受到人类活动和环境压力的威胁。有效的保护需要强有力的指标来评估生态健康。本研究为埃塞俄比亚中部Dinki流域的溪流开发了一种基于大型无脊椎动物的多尺度指数（MMI）。基于干扰响应、Mann-Whitney U检验、Spearman相关和箱形图分析，从37个潜在指标中筛选出5个核心指标：Ephemeroptera-Odonata-Trichoptera百分比（%EOT）、Trichoptera百分比（%Trico）、半翅目丰度、Family bioindex （FBI）和Average Score Per Taxon （ASPT）。MMI使用受影响地点和参考地点的核心指标的最小和最大总和分数来计算。Dinki、Zego和Dense站点的健康状况最差，得分最低（10.22），而Gedamoch和部分Zego和Dense站点的健康状况最高（22.43），表明健康状况非常好。在5-25个潜在范围的基础上，将站点划分为5个生态健康类别。使用Spearman的rs、RDA、箱形图和Mann-Whitney U测试进行验证，证实了核心指标和MMI都有效地区分了受影响地点和参考地点，突出了其作为埃塞俄比亚高地溪流快速生态评估实用工具的价值。

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引用次数: 0

The redox discontinuity layer depth drives macroinvertebrate community structure and functional diversity in Tabasco wetlands 氧化还原不连续层深度驱动塔巴斯科湿地大型无脊椎动物群落结构和功能多样性

IF 2 4区环境科学与生态学 Q2 LIMNOLOGY

Limnologica

Pub Date : 2026-01-01 Epub Date: 2026-01-17 DOI: 10.1016/j.limno.2026.126309

Juan Carlos Rubio-Polania , Cinthia Trinidad-Ocaña , Juan Juarez Flores , Everardo Barba-Macías

Wetlands are critically threatened ecosystems whose conservation requires understanding multi-faceted community assembly rules. This study presents a comprehensive assessment of macroinvertebrate communities across 16 wetlands in Tabasco, Mexico, integrating taxonomic, functional, and biomass-based perspectives. We reveal a fundamental decoupling between numerical abundance and biomass in units of ash-free dry weight (AFDW), with each metric responding to distinct environmental drivers. While abundance was shaped by local temperature and productivity gradients, biomass distribution was structured by broad-scale spatial patterns. This decoupling extended to functional organization, where abundance-based trait space was unidimensional, but biomass-based space was multidimensional, indicating multiple strategies for energy accumulation. We found exceptionally high beta diversity (>0.91) dominated by species turnover, confirming these wetlands as a mosaic of unique habitats. Local Contribution to Beta Diversity (LCBD) analysis identified sites of high conservation value (e.g., CEN.S8) and others indicating potential degradation. Functionally, low diversity at sites dominated by pollution-tolerant species suggested anthropogenic stress, though weak links between functional indices and measured variables pointed to unquantified chemical filters. A key finding was the redox discontinuity layer (RDL) depth as a primary environmental driver, structuring communities across all metrics and highlighting sediment biogeochemistry as a master variable. Vegetation productivity (EVI) emerged as the main driver of compositional uniqueness. Our integrated approach demonstrates that effective conservation of these threatened ecosystems requires monitoring that combines abundance and biomass metrics, incorporates sediment redox conditions and vegetation structure, and advances toward direct quantification of industrial contaminants to diagnose true ecosystem health.

湿地是受到严重威胁的生态系统，其保护需要了解多方面的群落聚集规则。本文从分类、功能和生物量的角度对墨西哥塔巴斯科16个湿地的大型无脊椎动物群落进行了综合评估。我们揭示了数值丰度与以无灰干重（AFDW）为单位的生物量之间的基本解耦，每个度量都响应不同的环境驱动因素。虽然丰度受当地温度和生产力梯度的影响，但生物量分布受大尺度空间格局的影响。这种解耦扩展到功能组织，其中基于丰度的特征空间是一维的，而基于生物量的空间是多维的，表明能量积累的多种策略。我们发现了异常高的β多样性（>0.91），主要是物种更替，证实了这些湿地是一个独特栖息地的马赛克。本地对Beta多样性的贡献（LCBD）分析确定了具有高保护价值的地点（如CEN）。S8)和其他指示潜在退化的。在功能上，耐污染物种占主导地位的地点的低多样性表明人为压力，尽管功能指数和测量变量之间的弱联系指向未量化的化学过滤器。一个关键的发现是氧化还原不连续层（RDL）深度是一个主要的环境驱动因素，在所有指标中构建群落，并强调沉积物生物地球化学是一个主要变量。植被生产力（EVI）是构成独特性的主要驱动力。我们的综合方法表明，有效保护这些受威胁的生态系统需要监测，结合丰度和生物量指标，结合沉积物氧化还原条件和植被结构，并在直接量化工业污染物方面取得进展，以诊断真正的生态系统健康。

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引用次数: 0

Nematode assemblages associated to littoral submerged aquatic vegetation at the Bacalar Lake, Quintana Roo, Mexico 与墨西哥金塔纳罗奥巴卡拉湖沿岸淹没水生植被相关的线虫组合

IF 2 4区环境科学与生态学 Q2 LIMNOLOGY

Limnologica

Pub Date : 2026-01-01 Epub Date: 2026-01-19 DOI: 10.1016/j.limno.2026.126310

Alberto de Jesús-Navarrete , Abel Abraham Vargas-Espósitos

We investigated composition, distribution, diversity, and functional traits associated with submerged vegetation of nematode assemblages at Bacalar Lake, southeastern Mexico. Six different submerged vegetation species were found at eight sample sites of the Bacalar Lake. The nematode community was composed of 25 families and 46 genera. Dorylaimidae was the most diverse in genera with Ischiodorylaimus as the most abundant. Eleocharis cellulosa showed the highest genus richness in November (27 genera). Chara sp. showed the highest Shannon-Wiener diversity values in March (3.97). The highest Pielou's evenness index values were found for Vallisneria sp. (0.88) in March. There was a dominance of suction feeders in most types of vegetation (46.4 %) and nematodes c-p4 (50.79 %). Some genera were shown to be affected by environmental variables, such as Ischiodorylaimus by water temperature. The diversity and composition did not show significant differences between vegetation types, only between sampling events, while trophic groups and strategy life only between sites. There were more nematode genera at vegetation species (46) than reported in sediments (29). Hence, we conclude that the aquatic macrophytes in Bacalar Lake harbour a distinct nematode community with specific adaptations.

研究了墨西哥东南部Bacalar湖线虫群落的组成、分布、多样性和与淹没植被相关的功能特征。在巴卡拉湖的8个采样点发现了6种不同的淹没植被。线虫群落由25科46属组成。dorylylaimidae属种类最多，其中Ischiodorylaimus属数量最多。11月的Eleocharis cellulosa属丰富度最高（27个属）。夏拉种的Shannon-Wiener多样性值在3月份最高（3.97）。3月份缬草（valisneria sp.）的Pielou均匀度指数最高，为0.88。大多数植被类型以吸吮性取食者为主（46.4% %），c-p4线虫为主（50.79 %）。一些属被证明受环境变量的影响，如Ischiodorylaimus受水温的影响。多样性和组成在不同的植被类型之间没有显著差异，在不同的采样事件之间存在显著差异，而营养类群和策略生命在不同的样地之间存在显著差异。植被中的线虫属（46个）比沉积物中的线虫属（29个）多。因此，我们得出结论，Bacalar湖水生植物中有一个独特的线虫群落，具有特定的适应性。

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引用次数: 0

Digestive tract morphology, feeding habits, and diet composition of Hyporhamphus limbatus from Southwest Vietnam 越南西南部边缘小鳗消化道形态、摄食习性及饮食组成

IF 2 4区环境科学与生态学 Q2 LIMNOLOGY

Limnologica

Pub Date : 2026-01-01 Epub Date: 2025-12-22 DOI: 10.1016/j.limno.2025.126308

Vinh Quoc Nguyen, Vuong Van Ly, Phuc Le Hoang Nguyen, Lam Thi Thao Vo, Anh Ngoc Tran, Ton Huu Duc Nguyen, Quang Minh Dinh

This study investigated the trophic morphology, feeding habits, and natural diet of Hyporhamphus limbatus in Bac Lieu and Ca Mau province, Southwest Vietnam. A total of 960 individuals were sampled monthly from August 2023 to July 2024 at two sites, Vinh Phuoc, Bac Lieu and Dam Doi, Ca Mau (∼40 fish per site per month). Morphological assessments included mouth orientation, dentition, tongue structure, gill arch anatomy, and intestinal configuration. The mean relative gut length (RGL) was 0.34, consistent with carnivory. Gut content analyses were performed on the subset of fish with non-empty guts (n = 703). Small fishes dominated the diet (58.65 %), followed by ants (13.64 %) and shrimp (12.46 %); other items each contributed < 10 %. PERMANOVA indicated a significant seasonal effect on diet composition (df = 1, F = 11.24, p < 0.001), with fish biomass in guts higher during the wet season, whereas ants increased markedly during rainfall events. No significant dietary differences were detected between sexes or sampling sites. The morphology and diet demonstrate a specialized, primarily piscivorous strategy, which has implications for fisheries resource management and the potential development of aquaculture in Southwest Vietnam.

本研究调查了越南西南部北寮省和金茂省的limbatus的营养形态、摄食习性和自然食性。从2023年8月至2024年7月，在Vinh Phuoc， Bac Lieu和Dam Doi， Ca Mau两个地点每月共采集960只鱼（每个地点每月约40只鱼）。形态学评估包括口腔取向、牙列、舌结构、鳃弓解剖和肠道结构。平均相对肠长（RGL）为0.34，与肉食性一致。对非空肠鱼亚组进行肠道含量分析（n = 703）。以小鱼类为主（58.65 %），其次是蚂蚁（13.64 %）和虾类（12.46 %）；其他项目各贡献<； 10 %。PERMANOVA表明，季节对饲料组成有显著影响（df = 1, F = 11.24, p <； 0.001），肠道中鱼类的生物量在雨季较高，而蚂蚁在降雨期间显著增加。在性别或采样地点之间没有发现显著的饮食差异。形态和食性显示出一种专门的，主要是食鱼的策略，这对越南西南部渔业资源管理和水产养殖的潜在发展具有重要意义。

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引用次数: 0

Food web modeling and network analysis unravel contrasting ecosystem functions in Ethiopian Rift Valley lakes 食物网建模和网络分析揭示了埃塞俄比亚裂谷湖泊对比生态系统功能

IF 2 4区环境科学与生态学 Q2 LIMNOLOGY

Limnologica

Pub Date : 2026-01-01 Epub Date: 2025-12-04 DOI: 10.1016/j.limno.2025.126297

Mathewos Hailu , Seyoum Mengistou , Tadesse Fetahi

Ecosystem-based management is an integrated approach that recognizes biodiversity, the complexity of social ecological systems, and the importance of ecosystem connections. To support this approach, we compared the food web structure and function of three Ethiopian Rift Valley lakes, Lake Ziway, Hawassa, and Chamo, using Ecopath with Ecosim models. A linear inverse modeling approach was employed to estimate unmeasured flows and quantify model uncertainty. The total system throughput was lowest in Lake Ziway (13.9 kt/km²/yr) compared with Lake Chamo (28.8 kt/km²/yr) and Lake Hawassa (36.8 kt/km²/yr), likely reflecting impacts of high turbidity on primary production. Network analysis suggests Lake Chamo has a more mature and organized structure, whereas Lakes Hawassa and Ziway appear more constrained by fisheries exploitation, with Lake Ziway also impacted by high sediment loads. While Lake Chamo showed greater stability, Lake Ziway exhibited the highest nutrient recycling (Finn’s Cycling Index), a potential indicator of system stress. Simulation scenarios exploring perturbations revealed that decreased primary production could increase overall food web efficiency, while recovery of fish biomass may enhance system resilience. This study highlights the value of a holistic, modeling approach in developing tailored, ecosystem-based management strategies for lake ecosystems facing distinct anthropogenic pressures.

基于生态系统的管理是一种综合方法，它认识到生物多样性、社会生态系统的复杂性和生态系统联系的重要性。为了支持这一方法，我们使用Ecopath和Ecosim模型比较了埃塞俄比亚东非大裂谷的三个湖泊——Ziway湖、Hawassa湖和Chamo湖的食物网结构和功能。采用线性逆建模方法估计未测流量，量化模型不确定性。与查莫湖（28.8 kt/km²/年）和哈瓦萨湖（36.8 kt/km²/年）相比，Ziway湖的总系统吞吐量最低（13.9 kt/km²/年），这可能反映了高浊度对初级生产的影响。网络分析表明，查莫湖具有更成熟、更有组织的结构，而哈瓦萨湖和兹威湖受渔业开发的制约更大，兹威湖也受到高泥沙负荷的影响。Chamo湖表现出更强的稳定性，而Ziway湖表现出最高的养分循环（Finn’s Cycling Index），这是一个潜在的系统压力指标。探索扰动的模拟情景显示，初级产量的减少可以提高食物网的整体效率，而鱼类生物量的恢复可能会增强系统的弹性。本研究强调了整体建模方法在为面临不同人为压力的湖泊生态系统制定量身定制的、基于生态系统的管理策略方面的价值。

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引用次数: 0

Seasonal river connections modulate community structure in (sub) tropical temporary pools 季节性河流连接调节（亚热带）临时水池的群落结构

IF 2 4区环境科学与生态学 Q2 LIMNOLOGY

Limnologica

Pub Date : 2026-01-01 Epub Date: 2025-12-02 DOI: 10.1016/j.limno.2025.126298

Grite Nelson Mwaijengo , Bram Vanschoenwinkel , Luc Brendonck

In natural river systems in arid and semi-arid lands, surrounding floodplains may contain temporary pools. Some of these may be mainly rain-filled (endorheic systems) while others may be partly rain-fed but connect to the flooding river during a good rainy season (river-connected pools). However, how seasonal river flooding affects the community structure in temporary floodplain pools is not well understood, particularly in the Afro-tropical region. Here, we studied the role of seasonal river connections in modulating water quality and benthic macroinvertebrate community structure and functional feeding groups in a set of endorheic versus river-connected temporary pools in a river-floodplain ecosystem in northeastern Tanzania. Benthic macroinvertebrate communities from the two habitats were significantly differentiated. Spatial species turnover (β-diversity) was higher in river-connected pools, but endorheic ones supported a higher taxon richness (alpha diversity). Benthic macroinvertebrate community dissimilarity between pools was largely determined by turnover rather than by nestedness. Hydrological connectivity was positively associated with electric conductivity and negatively associated with nutrient concentrations in the river-connected pools. In addition, the river facilitated fish dispersal, which likely excluded predation sensitive taxa such as the large branchiopod crustaceans Streptocephalus bourquinii and Streptocephalus wirminghausi. Taxon richness of collector-gatherers and scrapers was significantly different between pool types. Indicator species analysis revealed no specific fauna unique to river-connected pools. This study illustrates that land management schemes that aim to preserve temporary-pool biodiversity should strive to include both endorheic and river-connected pools to support high regional biodiversity, potentially with a priority for the more diverse endorheic systems.

在干旱和半干旱地区的天然河流系统中，周围的洪泛平原可能包含临时水池。其中一些可能主要是雨水充沛的（内源性系统），而另一些可能部分雨水充足，但在雨季与洪水相连（与河流相连的水池）。然而，季节性河流洪水如何影响临时洪泛区水池中的群落结构尚不清楚，特别是在非洲热带地区。在这里，我们研究了季节性河流连接在调节水质和底栖大型无脊椎动物群落结构和功能摄食群体中的作用，这些底栖大型无脊椎动物群落结构和功能摄食群体位于坦桑尼亚东北部的河流-洪泛平原生态系统中。两种生境的底栖大型无脊椎动物群落差异显著。河流连通池的空间物种周转（β-多样性）较高，而内河池的物种丰富度（α多样性）较高。池间底栖大型无脊椎动物群落差异主要由周转而非巢性决定。水文连通性与电导率呈正相关，与河流连接池中的营养物质浓度负相关。此外，河流促进了鱼类的扩散，这可能排除了对捕食敏感的类群，如大型支足甲壳类动物布氏链头和温明豪链头。收集者-采集者和刮刀者的分类丰富度在不同池类型间存在显著差异。指示物种分析显示，与河流相连的水池没有特定的动物群。该研究表明，旨在保护临时池生物多样性的土地管理方案应努力包括内河池和河流相连的池，以支持高区域生物多样性，可能优先考虑更多样化的内河系统。

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引用次数: 0

Climate change increases functional richness and shifts trait composition of benthic macroinvertebrate assemblages along the river continuum 气候变化增加了河流连续体底栖大型无脊椎动物群落的功能丰富度，改变了它们的特征组成

IF 2 4区环境科学与生态学 Q2 LIMNOLOGY

Limnologica

Pub Date : 2026-01-01 Epub Date: 2025-12-22 DOI: 10.1016/j.limno.2025.126307

Marie Zhai, Michal Janáč, Michal Horsák, Jindřiška Bojková

The recently observed massive reorganisations of macroinvertebrate assemblages in streams are usually attributed to the combined effects of changes in water quality and climate. The consequences of the associated functional changes for ecosystem services and future development are still unknown. In this study, we try to disentangle the effects of climate change on the functional structure from other anthropogenic effects. To do so, we examine functional richness and composition of biological traits in macroinvertebrate assemblages, coming from 65 near-natural streams in the Czech Republic, where anthropogenic stressors apart from those due to climate change were minimal. We sampled the macroinvertebrates using a standardized biomonitoring sampling protocol during three periods from 1997 to 2015. To understand the patterns along the river continuum, we covered a substantial gradient of source distance (3–260 km). The assemblages previously showed a high increase in total species richness and abundances of many native species. As functional richness directly depends on species richness by virtue of probability, we introduced a novel concept of rarefied functional richness, where assemblages of the species richer period were rarefied to equal the number of species in the less species rich period at each site. We found a significant functional enrichment, predominantly independent of the higher number of species and tending towards a unimodal pattern along the source distance. The functional composition overall shifted to that of downstream sections in all source distance intervals, based mainly on life cycle, body size, locomotion, representation of several feeding groups, and dispersal abilities. The shift was mostly indicative of the substantial effects of lower flow conditions associated with fine sediment deposition, increased temperature and an increase in resources, mainly for collectors/gatherers and predators.

最近观察到的溪流中大型无脊椎动物群落的大规模重组通常归因于水质和气候变化的综合影响。相关功能变化对生态系统服务和未来发展的影响尚不清楚。在本研究中，我们试图将气候变化对功能结构的影响与其他人为影响区分开来。为此，我们研究了来自捷克共和国65条近自然溪流的大型无脊椎动物群落中生物特征的功能丰富度和组成，这些河流除气候变化外人为压力源最小。在1997年至2015年的三个时期，我们使用标准化的生物监测采样方案对大型无脊椎动物进行了采样。为了了解沿河流连续体的格局，我们覆盖了相当大的源距离梯度（3-260 km）。这些组合以前显示出物种总丰富度和许多本地物种丰富度的高增加。由于功能丰富度直接取决于物种丰富度的概率，我们引入了稀薄功能丰富度的新概念，即将物种丰富期的物种组合稀薄到与物种不丰富期的物种数量相等。我们发现一个显著的功能丰富，主要独立于较高的物种数量，并倾向于单峰模式沿源距离。在所有源距离区间内，功能组成总体上向下游部分转移，主要基于生命周期、体型、运动、几种摄食群体的代表性和扩散能力。这种变化主要表明了与细沉积物沉积、温度升高和资源增加相关的低流量条件的实质性影响，主要是对收集者/采集者和捕食者。

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