Limnology and Oceanography最新文献_第9页

Substrate availability may limit the response of tropical bacterioplankton biomass to warming 底质可用性可能限制热带浮游细菌生物量对气候变暖的反应

IF 3.8 1区地球科学

Limnology and Oceanography Pub Date : 2024-08-13 DOI: 10.1002/lno.12647

Xosé Anxelu G. Morán, Maria Ll. Calleja, Federico Baltar, Luis Silva, Mohd Ikram Ansari, Paloma Carrillo de Albornoz, Carlos M. Duarte, Christian Lønborg

{"title":"Substrate availability may limit the response of tropical bacterioplankton biomass to warming","authors":"Xosé Anxelu G. Morán, Maria Ll. Calleja, Federico Baltar, Luis Silva, Mohd Ikram Ansari, Paloma Carrillo de Albornoz, Carlos M. Duarte, Christian Lønborg","doi":"10.1002/lno.12647","DOIUrl":"10.1002/lno.12647","url":null,"abstract":"The response of heterotrophic bacterioplankton to the addition of macrophytic dissolved organic matter (DOM) and temperature was investigated in the Red Sea. We added 40 μmol C L−1 of leachates obtained from seagrass and mangrove leaves to natural bacterial communities, incubated them at three temperatures (25.5°C found in situ plus 3°C below and above that value) and monitored the microbial and biogeochemical responses over 4 d. Seagrass and mangrove DOM, important allochthonous sources in tropical oligotrophic regions, had distinct chemical characteristics compared to unamended seawater, with mangrove substrates containing comparatively more nitrogen and protein-like fluorescent DOM than seagrass. Specific growth rates (μ) increased twofold in the seagrass and mangrove treatments (1.0 and 0.8 d−1, respectively) relative to the seawater control (0.4 d−1). The biomass of heterotrophic bacteria generally reflected μ changes, reaching maximum values of 16.8 and 17.3 μg C L−1 in the seagrass and mangrove treatments, respectively, compared to just 2.6 μg C L−1 in seawater. The increase in μ values due to experimental warming followed the metabolic theory of ecology, mostly because of enhanced exoenzymatic activity, while cell size decreased as predicted by the temperature–size rule (mean −3% per °C increase). Although the labile nature of the specific seagrass and mangrove DOM leachates was clearly demonstrated, we conclude that tropical heterotrophic bacteria may have limited capability to increase their biomass as a consequence of future warming, even in the presence of high loadings of macrophytic DOM.","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":"69 9","pages":"2043-2056"},"PeriodicalIF":3.8,"publicationDate":"2024-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/lno.12647","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141980531","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Efficient oxidation attenuates porewater-derived methane fluxes in mangrove waters 高效氧化作用可减轻红树林水体中源于孔隙水的甲烷通量

IF 3.8 1区地球科学

Limnology and Oceanography Pub Date : 2024-08-13 DOI: 10.1002/lno.12639

Yvonne Y. Y. Yau, Alex Cabral, Gloria Reithmaier, Luiz C. Cotovicz Jr, João Barreira, Gwenaël Abril, Cedric Morana, Alberto V. Borges, Wilson Machado, José M. Godoy, Stefano Bonaglia, Isaac R. Santos

{"title":"Efficient oxidation attenuates porewater-derived methane fluxes in mangrove waters","authors":"Yvonne Y. Y. Yau, Alex Cabral, Gloria Reithmaier, Luiz C. Cotovicz Jr, João Barreira, Gwenaël Abril, Cedric Morana, Alberto V. Borges, Wilson Machado, José M. Godoy, Stefano Bonaglia, Isaac R. Santos","doi":"10.1002/lno.12639","DOIUrl":"10.1002/lno.12639","url":null,"abstract":"Mangroves store significant amounts of carbon in both sediment and water. Methane (CH4) is often produced in anoxic, organic-rich sediments during carbon degradation and released to overlying waters via porewater exchange. Yet, a portion of CH4 can be oxidized to CO2 before emission. Here, we investigate whether CH4 oxidation impacts its emissions using high-temporal resolution CH4 concentration and stable isotope (δ13C-CH4) observations collected over 14 tidal cycles in 2 Brazilian mangrove creeks with no river inputs. We found higher CH4 concentrations (~ 150 nM) more depleted in 13C (−75‰) during low tide than high tide at both creeks. Similar δ13C-CH4 values between low tide surface waters and porewaters further suggest tidally driven porewater exchange as the main source of CH4. More 13C-enriched CH4 in surface waters and surface sediments than deep sediments indicate partial CH4 oxidation prior to exchange with the atmosphere. A stable isotope mass balance revealed that 17–58% of CH4 was oxidized at rates of 3–25 μmol m−2 d−1 in the water column of tidal creeks. A larger portion of deep porewater CH4 (45–61%) was oxidized in sediments prior to porewater exchange with surface creek waters. The two mangrove creeks had average water–air CH4 fluxes of 51–109 μmol m−2 d−1 over spring-neap tidal cycles. These aquatic CH4 emissions offset only < 3% of the mangroves' soil carbon sequestration. Overall, CH4 oxidation in both surface water and sediment attenuated CH4 emissions to the atmosphere.","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":"69 9","pages":"1997-2014"},"PeriodicalIF":3.8,"publicationDate":"2024-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/lno.12639","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141980652","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Aerenchyma in emergent plants and rhizospheric microbial communities promote methane fluxes in wetlands 出水植物的根瘤和根瘤微生物群落促进湿地甲烷通量

IF 3.8 1区地球科学

Limnology and Oceanography Pub Date : 2024-08-12 DOI: 10.1002/lno.12653

Shaozhuang Guo, Songhe Zhang, Xin Lv, Hezhou Chen, Jie Chen, Junfeng Gao, Wenming Zhang

{"title":"Aerenchyma in emergent plants and rhizospheric microbial communities promote methane fluxes in wetlands","authors":"Shaozhuang Guo, Songhe Zhang, Xin Lv, Hezhou Chen, Jie Chen, Junfeng Gao, Wenming Zhang","doi":"10.1002/lno.12653","DOIUrl":"10.1002/lno.12653","url":null,"abstract":"Wetlands are the largest natural source of CH4 globally, yet our understanding of how environmental parameters and microorganisms affect the production and emission of CH4 in emergent plant–sediment systems remains limited. In this study, CH4 fluxes were investigated in a wetland with Canna indica for 42 d, as well as nutrients and microbial community. It was found that the chimney effect formed by aerenchyma in roots, stems, and leaves of C. indica promoted the emission and oxidation of CH4 in the wetland and reduced the CH4 concentration in sediments. Canna indica reduced the nutrient release from surface sediments into the overlying water. Pearson correlation analysis showed that temperature, pH, and oxidation–reduction potential were the main influencing factors for CH4 production and oxidation in the wetland. Canna indica inhibited the diversity of archaeal community but promoted the diversity of bacterial community in the rhizosphere. Stochastic processes had a greater impact on bacterial and archaeal succession trajectories in wetland sediments. Network analysis showed that C. indica promoted interactions among bacteria and archaea that enhanced their ability to resist environmental interference. The well-developed aerenchyma of C. indica provided an important passage for the transport of CH4 from sediments to the atmosphere and shaped the microbial community structure in the rhizosphere. Meanwhile, CH4 emissions were also constrained by several variables, such as temperature and physiological adaptation in the long term. Thus, it is necessary to plant emergent plants in areas with low CH4 emissions and optimize plant configuration in the context of global warming.","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":"69 9","pages":"2109-2122"},"PeriodicalIF":3.8,"publicationDate":"2024-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141973807","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Patchiness of plankton communities at fronts explained by Lagrangian history of upwelled water parcels 上涌水团的拉格朗日历史解释了前沿浮游生物群落的斑块性

IF 3.8 1区地球科学

Limnology and Oceanography Pub Date : 2024-08-12 DOI: 10.1002/lno.12654

Shailja Gangrade, Inès Mangolte

{"title":"Patchiness of plankton communities at fronts explained by Lagrangian history of upwelled water parcels","authors":"Shailja Gangrade, Inès Mangolte","doi":"10.1002/lno.12654","DOIUrl":"10.1002/lno.12654","url":null,"abstract":"The transport of plankton by highly dynamic (sub)mesoscale currents—often associated with fronts and eddies—shapes the structure of plankton communities on the same time scales as biotic processes, such as growth and predation (days–weeks). The resulting biophysical couplings generate heterogeneities in their finescale distributions (1–10 km), or “patchiness.” Here, we test the hypothesis that cross-frontal plankton patchiness at a front found 200–250 km offshore in the California Current System was influenced by wind-driven upwelling conditions upstream of the front. We show that in situ Eulerian measurements (cross-frontal transects) can be interpreted in a Lagrangian framework by using satellite-derived current velocities to trace water parcels backward in time to their coastal origins. We find that the majority of the water parcels sampled at this front originated along the central California coast during different episodic wind-driven upwelling pulses and followed various trajectories before converging temporarily at the front. In response to nutrient injections at the coast, plankton communities transformed during their journeys from the coast to the sampling zone, with a succession of phytoplankton and zooplankton blooms. The cross-frontal sampling captured the convergence of these distinct water parcels at different points in their biological histories, which resulted in the observed spatial patchiness. Our results suggest that identifying the processes controlling frontal plankton communities requires understanding them in the context of their spatial and temporal histories. In particular, Lagrangian approaches should be more widely applied to understand critical ecological patterns in highly dynamic systems.","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":"69 9","pages":"2123-2137"},"PeriodicalIF":3.8,"publicationDate":"2024-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/lno.12654","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141973822","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Long-range transport of littoral methane explains the metalimnetic methane peak in a large lake 沿岸甲烷的长程飘移解释了一个大型湖泊中的金属沉积甲烷峰值

IF 3.8 1区地球科学

Limnology and Oceanography Pub Date : 2024-08-11 DOI: 10.1002/lno.12652

Santona Khatun, Jasmine S. Berg, Didier Jézéquel, Marthe Moiron, Nicolas Escoffier, Carsten J Schubert, Damien Bouffard, Marie-Elodie Perga

{"title":"Long-range transport of littoral methane explains the metalimnetic methane peak in a large lake","authors":"Santona Khatun, Jasmine S. Berg, Didier Jézéquel, Marthe Moiron, Nicolas Escoffier, Carsten J Schubert, Damien Bouffard, Marie-Elodie Perga","doi":"10.1002/lno.12652","DOIUrl":"10.1002/lno.12652","url":null,"abstract":"In large and stratified lakes, substantial methane stocks are often observed within the metalimnion. The origin of the methane (CH4) accumulated in the metalimnion during stratification, which can sustain significant emissions during convective mixing, is still widely debated. While commonly attributed to the transport of methane produced anaerobically ex situ, recent evidence suggests that oxic in situ methane production could also contribute to metalimnetic methane peaks. Here, we assessed the origin, that is, pelagic CH4 production or transport of sublittoral CH4 through the interflow, of metalimnetic methane in Lake Geneva, the largest lake in Western Europe. Microbial diversity data do not support the hypothesis of oxic methane production in the metalimnion. In contrast, both spatial and temporal surveys of methane show that maxima occur at depths and sites most affected by the Rhône River inflow. Methane δ13C values point to an anaerobic sublittoral methane source, within a biogeochemical hotspot close to the river delta region, and an efficient transport across several kilometers in a vertically well-constrained metalimnion. Our current findings emphasize the indirect role of river interflows for the long-range transport of CH4 produced in sediment biogeochemical hotspots, even for large lakes where sublittoral habitats represent a fairly limited fraction of the lake volume.","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":"69 9","pages":"2095-2108"},"PeriodicalIF":3.8,"publicationDate":"2024-08-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/lno.12652","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141973821","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Decoupled cycling of particulate cadmium and phosphorus in the subtropical Northwest Pacific 西北太平洋亚热带地区颗粒镉和磷的解耦循环

IF 3.8 1区地球科学

Limnology and Oceanography Pub Date : 2024-08-08 DOI: 10.1002/lno.12635

Kan Zhang, Kuanbo Zhou, Yihua Cai, Zhongwei Yuan, Yaojin Chen, Feipeng Xu, Xin Liu, Zhimian Cao, Minhan Dai

{"title":"Decoupled cycling of particulate cadmium and phosphorus in the subtropical Northwest Pacific","authors":"Kan Zhang, Kuanbo Zhou, Yihua Cai, Zhongwei Yuan, Yaojin Chen, Feipeng Xu, Xin Liu, Zhimian Cao, Minhan Dai","doi":"10.1002/lno.12635","DOIUrl":"10.1002/lno.12635","url":null,"abstract":"We examined the spatial variation in size-fractionated (0.8–51 and > 51 μm) particulate cadmium (Cd) and phosphorus (P) based on a large dataset collected during a GEOTRACES Section cruise (GP09) in the North Pacific Subtropical Gyre (NPSG) to better understand the interrelationship between Cd and P biogeochemical cycles. Concentrations of particulate Cd (0.06–2.15 pmol L−1) and P (0.33–10.19 nmol L−1) showed an initial increase with depth followed by a decrease, and were among the lowest observed in the global ocean. Bulk particulate Cd : P ratios in the euphotic zone, indicative of phytoplankton Cd assimilation, showed strong geographic variability averaging 0.05 ± 0.02 within the NPSG interior vs. 0.14 ± 0.04 pmol nmol−1 at the southern boundary. Cadmium to P remineralization ratio in the mesopelagic zone had a roughly similar stoichiometry as what was produced in the euphotic zone, being ~ 0.05 ± 0.01 in the NPSG interior vs. 0.21 ± 0.04 pmol nmol−1 at the southern boundary. Cd–P decoupling was reflected in the elements' vertical distribution, showing unsynchronized changes through the water column, consistent with Cd–P differential remineralization resulting from multiple Cd and P pools. The Cd–P relationship also differed between small and large particles, suggesting differences in Cd assimilation among phytoplankton assemblages as well as particle dynamic processes. Our results highlight complex processes fractionating Cd from P in the oligotrophic ocean and complicate the use of Cd as a palaeo-phosphate proxy.","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":"69 9","pages":"1941-1954"},"PeriodicalIF":3.8,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141910358","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Does polymixis complicate prediction of high‐frequency dissolved oxygen in lakes and reservoirs? 多混杂性是否会使湖泊和水库的高频溶解氧预测复杂化？

IF 4.5 1区地球科学

Limnology and Oceanography Pub Date : 2024-08-07 DOI: 10.1002/lno.12650

Caleb J. Robbins, Jeffrey M. Sadler, Dennis Trolle, Anders Nielsen, Nicole D. Wagner, J. Thad Scott

{"title":"Does polymixis complicate prediction of high‐frequency dissolved oxygen in lakes and reservoirs?","authors":"Caleb J. Robbins, Jeffrey M. Sadler, Dennis Trolle, Anders Nielsen, Nicole D. Wagner, J. Thad Scott","doi":"10.1002/lno.12650","DOIUrl":"https://doi.org/10.1002/lno.12650","url":null,"abstract":"As lake and reservoir ecosystems transition across major environmental regimes (e.g., mixing regime) resulting from anthropogenic change, setting predictive expectations is imperative. We tested the hypothesis that (dissolved) oxygen is more predictable in monomictic reservoirs that thermally stratify throughout the summer (warm) season compared to polymictic reservoirs that stratify intermittently. Using two‐hourly vertical profiles of oxygen, we compared daily‐aggregated errors of oxygen predictions from random forests across and within two monomictic and two polymictic reservoirs in the south‐central (subtropical) USA. Although one monomictic reservoir was typically more predictable than the polymictic reservoirs, the hypereutrophic, small monomictic reservoir had less predictable oxygen patterns potentially related to rapid oxygen cycling and intrusions of oxygenated waters in the hypolimnion without mixing. Daily mixing did not relate strongly to model errors. Water temperature, depth, and wind were the most important predictors, but were not clearly related to season or mixing. Lastly, we compared multiple model types (regression, neural network, and process‐based) in one polymictic reservoir to test how our interpretations of oxygen predictability were sensitive to model type, finding that the models generally agreed; however, the process‐based model poorly predicted oxygen in the middle of the vertical profiles (5 m) where most models performed poorly due to a temporally unstable, vacillating metalimnion. Our results suggest predicting reservoir oxygen dynamics may be easier in stratified reservoirs, but eutrophication and complex hydrodynamics may cause forecasting surprises especially for those who use or manage water resources in mono‐ or dimictic reservoirs.","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":"83 1","pages":""},"PeriodicalIF":4.5,"publicationDate":"2024-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141904680","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Warming stimulates mangrove carbon sequestration in rising sea level at their northern limit: An in situ simulation 气候变暖刺激红树林在其北部极限海平面上升时固碳：原位模拟

IF 3.8 1区地球科学

Limnology and Oceanography Pub Date : 2024-08-06 DOI: 10.1002/lno.12655

Peiyang Qiao, Ying Dong, Xiaoxuan Gu, Lian Xu, Mei Li, Wandong Chen, Li Lin, Xiaopin Ni, Luzhen Chen

{"title":"Warming stimulates mangrove carbon sequestration in rising sea level at their northern limit: An in situ simulation","authors":"Peiyang Qiao, Ying Dong, Xiaoxuan Gu, Lian Xu, Mei Li, Wandong Chen, Li Lin, Xiaopin Ni, Luzhen Chen","doi":"10.1002/lno.12655","DOIUrl":"10.1002/lno.12655","url":null,"abstract":"Global warming and sea-level rise are directly influencing the growth, distribution, and greenhouse gas emissions of mangrove forests. However, mangrove forests growing at their latitudinal limits are relatively susceptible to warming; nevertheless, few studies have focused on GHG emissions of latitudinal limits mangrove forests as related to global climate change. To address this knowledge gap, a multiyear in situ control experiment was established in a restored plantation at the northern distribution limit of Kandelia obovata, the most cold-tolerant mangrove species in China, to simulate both warming and sea-level rise. We investigated the growth patterns and sediment greenhouse gas emissions of a K. obovata population and identified the primary factors contributing to these changes. The results showed that warming and moderate sea-level rise enhanced biomass by more than 18%, indicating that warming stimulated plant growth while excessive sea-level rise inhibited it. The sediment greenhouse gas emissions ranged from 45.5 to 484.6 mgCO2 m−2 h−1, 5.6 to 590.3 μgCH4 m−2 h−1, and 11.4 to 385 μgN2O m−2 h−1, which increased with warming while decreased with sea-level rise, acting as the net source of greenhouse gas emission. Our study predicted that sea-level rise, while directly changing sediment properties, had combined effects with warming on these studied mangrove forests that were predicted to emit more greenhouse gases from sediments in the future. These findings indicated that K. obovata plantations within their latitudinal limits tend to accumulate more CO2 for biomass carbon storage under warming conditions, while stimulating sediment greenhouse gas emissions, which will offset their climate mitigating effect in future climatic scenarios.","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":"69 9","pages":"2138-2151"},"PeriodicalIF":3.8,"publicationDate":"2024-08-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141904694","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Invasive Ponto-Caspian amphipods are less carnivorous outside their native range 入侵的庞托-里海片脚类动物在其原生地以外的肉食性较弱

IF 3.8 1区地球科学

Limnology and Oceanography Pub Date : 2024-08-03 DOI: 10.1002/lno.12638

Denis Copilaș-Ciocianu, Andrius Garbaras, Eglė Šidagytė-Copilas

{"title":"Invasive Ponto-Caspian amphipods are less carnivorous outside their native range","authors":"Denis Copilaș-Ciocianu, Andrius Garbaras, Eglė Šidagytė-Copilas","doi":"10.1002/lno.12638","DOIUrl":"10.1002/lno.12638","url":null,"abstract":"A species' expansion beyond the native range is often assumed to be associated with an increased dietary niche breadth. However, empirical evidence remains limited due to a scarcity of studies comparing both the parental and invaded ranges. Here, we test the trophic niche expansion hypothesis by examining stable isotopes and functional morphology across native (NW Black Sea) and invaded (SE Baltic Sea) ranges of two amphipods, Dikerogammarus villosus and Pontogammarus robustoides, originating from the Ponto-Caspian region—a major source of species invading Holarctic inland waters. Stable isotopes revealed that both species underwent a marked dietary niche contraction by becoming less carnivorous in the invaded range. This dietary shift was morphologically mirrored by an overall reduction of functional traits related to predation. The magnitude of dietary and morphological change was greater in D. villosus. Our findings indicate that previous experimental reports of aggressive predation in D. villosus reflect opportunistic foraging and align with local stable isotope studies which generally indicate a low trophic position. We conclude that Ponto-Caspian species can undergo rapid dietary changes outside the native range, and that dietary niche expansion is not a prerequisite for successful non-native establishment.","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":"69 9","pages":"1984-1996"},"PeriodicalIF":3.8,"publicationDate":"2024-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141887433","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Vertical and horizontal variations in phytoplankton chlorophyll a in response to a looping super typhoon 浮游植物叶绿素 a 在超强台风影响下的垂直和水平变化

IF 3.8 1区地球科学

Limnology and Oceanography Pub Date : 2024-07-29 DOI: 10.1002/lno.12651

Ying Chen, Hui Zhao, Guoqi Han

{"title":"Vertical and horizontal variations in phytoplankton chlorophyll a in response to a looping super typhoon","authors":"Ying Chen, Hui Zhao, Guoqi Han","doi":"10.1002/lno.12651","DOIUrl":"10.1002/lno.12651","url":null,"abstract":"Previous studies suggested that the increase in surface chlorophyll a (Chl a) is due to nutrient upwelling or to the upward mixing of the subsurface Chl a maximum layer under the influence of tropical cyclones, while often ignoring the influence of the subsurface Chl a minimum layer and horizontal advection on Chl a. In this study, we show the important roles of the upward mixing of the subsurface Chl a minimum layer, horizontal advection, as well as the upwelling of the subsurface Chl a maximum layer, taking a looping super typhoon “Saola” in the northwest Pacific in August 2023 as an example. The temporal and spatial changes of Chl a and its physical properties were investigated by combining satellite, Argo, reanalysis, and model data. The results indicate that the combined effects of the upwelling of the subsurface Chl a maximum layer caused by wind stress curls and concurrent near-surface wind mixing were responsible for the surface Chl a increase in the looping area during the typhoon, while the 13% increase in the depth-integrated Chl a after the typhoon is mainly due to the nutrients brought by upwelling and subsequent biochemical processes. In the edge area affected by the typhoon, the surface Chl a decrease during the typhoon was mainly due to the upward mixing of the subsurface Chl a minimum layer (the effect of upwelling in this area is relatively weak). Furthermore, the horizontal advection led to a continuous surface Chl a decrease in the edge area after the typhoon. These findings could enhance understanding of Chl a dynamics post-tropical cyclones, aiding marine ecosystem prediction.","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":"69 9","pages":"2085-2094"},"PeriodicalIF":3.8,"publicationDate":"2024-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141857759","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0