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Ren Z, Gao H. Antibiotic resistance genes in integrated surface ice, cryoconite, and glacier-fed stream in a mountain glacier in Central Asia. ENVIRONMENT INTERNATIONAL 2024; 184:108482. [PMID: 38324929 DOI: 10.1016/j.envint.2024.108482] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Revised: 01/16/2024] [Accepted: 02/02/2024] [Indexed: 02/09/2024]
Abstract
Glacier ice, cryoconite, and glacier-fed streams are interconnected features that have important implications for the dynamics and distribution of abiotic and biotic materials. However, the presence and behavior of antibiotic resistance genes (ARGs) within these glacial environments remained largely unexplored. Addressing this gap, we hypothesized that ARGs are widely distributed and exhibit distinct yet interconnected patterns of diversity and dynamics in these glacial environments. Here, we investigated ARGs in a mountain glacier in Central Asia. A total of 944 ARGs, spanning 22 antibiotic classes, were identified, with 633 ARGs shared across all three environments. Cryoconite exhibited the highest ARG richness, followed by ice, while stream biofilm displayed the lowest value. Exploring ARG profiles, we observed a consistent pattern in terms of antibiotic class and resistance mechanism across all three environments. Beta-lactam resistance genes exhibited the highest diversity, followed by multidrug, glycopeptide, and MLS. The predominant mechanisms were antibiotic inactivation, antibiotic efflux, and target alteration. The most prevalent ARG is cls, followed by mdfA, ropB, fabI, and macB. The similarity in ARG profiles between surface ice and cryoconite samples was more pronounced than their resemblance to stream biofilm samples. The variations of ARG profiles between any pair of environments were largely contributed by turnover component. Further insights into microbial interactions revealed 2328 significant associations between 80 OTUs and 356 ARGs, indicating complex relationships. Certain OTUs, including those from the genera Polaromonas, Ferruginibacter, Hymenobacter, Phormidesmis, Novosphingobium, and Polymorphobacter, were speculated as potential hosts for a variety of ARGs. Our findings underscore the intricate dynamics of antibiotic resistance in glacial ecosystems, emphasizing the need for a holistic understanding of ARG distribution, diversity, and associations across diverse environmental compartments. This research contributes valuable insights into the potential ecological implications of antibiotic resistance dissemination in cold environments, particularly as influenced by increasing climate change.
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Affiliation(s)
- Ze Ren
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China
| | - Hongkai Gao
- Key Laboratory of Geographic Information Science (Ministry of Education), East China Normal University, Shanghai 200241, China.
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2
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Wang Y, Xu N, Chen B, Zhang Z, Lei C, Zhang Q, Gu Y, Wang T, Wang M, Penuelas J, Qian H. Metagenomic analysis of antibiotic-resistance genes and viruses released from glaciers into downstream habitats. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 908:168310. [PMID: 37944612 DOI: 10.1016/j.scitotenv.2023.168310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Revised: 10/31/2023] [Accepted: 11/01/2023] [Indexed: 11/12/2023]
Abstract
Glaciers serve as effective reservoirs of antibiotic resistance genes (ARGs) and viruses for millions of years. Climate change and anthropogenic activity have accelerated the melting of glaciers, but the patterns of release of ARGs and viruses from melting glaciers into downstream habitats remain unknown. We analyzed 171 metagenomic samples from glaciers and their downstream habitats and found that the abundance and diversity of ARGs were higher in glaciers (polar and plateau glaciers) than downstream habitats (Arctic Ocean, Qinghai Lake, and Yangtze River Basin), with the diversity of viruses having the opposite pattern. Proteobacteria and Actinobacteria were the main potential hosts of ARGs and viruses, and the richness of ARGs carried by the hosts was positively correlated with viral abundance, suggesting that the transmission of viruses in the hosts could disseminate ARGs. Source tracking indicated that >18 % of the ARGs and >25 % of the viruses detected in downstream habitats originated from glaciers, demonstrating that glaciers could be one of the potential sources of ARGs and viruses in downstream habitats. Increased solar radiation and emission of carbon dioxide mainly influenced the release of the ARGs and viruses from glaciers into downstream habitats. This study provides a systematic insight demonstrating the release of ARGs and viruses from the melting glaciers, potentially increasing ecological pressure.
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Affiliation(s)
- Yan Wang
- College of Environment, Zhejiang University of Technology, Hangzhou 310032, PR China
| | - Nuohan Xu
- College of Environment, Zhejiang University of Technology, Hangzhou 310032, PR China
| | - Bingfeng Chen
- College of Environment, Zhejiang University of Technology, Hangzhou 310032, PR China
| | - Zhenyan Zhang
- College of Environment, Zhejiang University of Technology, Hangzhou 310032, PR China
| | - Chaotang Lei
- College of Environment, Zhejiang University of Technology, Hangzhou 310032, PR China
| | - Qi Zhang
- College of Environment, Zhejiang University of Technology, Hangzhou 310032, PR China
| | - Yanpeng Gu
- College of Environment, Zhejiang University of Technology, Hangzhou 310032, PR China
| | - Tingzhang Wang
- Key Laboratory of Microbial Technology and Bioinformatics of Zhejiang Province, Hangzhou 310012, PR China
| | - Meixia Wang
- Key Laboratory of Microbial Technology and Bioinformatics of Zhejiang Province, Hangzhou 310012, PR China
| | - Josep Penuelas
- CSIC, Global Ecology Unit CREAF-CSIC-UAB, Bellaterra, Barcelona 08193, Catalonia, Spain; CREAF, Campus Universitat Autònoma de Barcelona, Cerdanyola del Vallès, Barcelona 08193, Catalonia, Spain
| | - Haifeng Qian
- College of Environment, Zhejiang University of Technology, Hangzhou 310032, PR China.
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3
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Gokul JK, Mur LAJ, Hodson AJ, Irvine-Fynn TDL, Debbonaire AR, Takeuchi N, Edwards A. Icescape-scale metabolomics reveals cyanobacterial and topographic control of the core metabolism of the cryoconite ecosystem of an Arctic ice cap. Environ Microbiol 2023; 25:2549-2563. [PMID: 37621052 DOI: 10.1111/1462-2920.16485] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Accepted: 08/06/2023] [Indexed: 08/26/2023]
Abstract
Glaciers host ecosystems comprised of biodiverse and active microbiota. Among glacial ecosystems, less is known about the ecology of ice caps since most studies focus on valley glaciers or ice sheet margins. Previously we detailed the microbiota of one such high Arctic ice cap, focusing on cryoconite as a microbe-mineral aggregate formed by cyanobacteria. Here, we employ metabolomics at the scale of an entire ice cap to reveal the major metabolic pathways prevailing in the cryoconite of Foxfonna, central Svalbard. We reveal how geophysical and biotic processes influence the metabolomes of its resident cryoconite microbiota. We observed differences in amino acid, fatty acid, and nucleotide synthesis across the cap reflecting the influence of ice topography and the cyanobacteria within cryoconite. Ice topography influences central carbohydrate metabolism and nitrogen assimilation, whereas bacterial community structure governs lipid, nucleotide, and carotenoid biosynthesis processes. The prominence of polyamine metabolism and nitrogen assimilation highlights the importance of recycling nitrogenous nutrients. To our knowledge, this study represents the first application of metabolomics across an entire ice mass, demonstrating its utility as a tool for revealing the fundamental metabolic processes essential for sustaining life in supraglacial ecosystems experiencing profound change due to Arctic climate change-driven mass loss.
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Affiliation(s)
- Jarishma K Gokul
- Department of Life Sciences, Cledwyn Building, Aberystwyth University, Wales, UK
- Department of Plant and Soil Sciences, University of Pretoria, Pretoria, South Africa
| | - Luis A J Mur
- Department of Life Sciences, Cledwyn Building, Aberystwyth University, Wales, UK
| | - Andrew J Hodson
- Department of Arctic Geology, University Centre in Svalbard (UNIS), Longyearbyen, Svalbard, Norway
- Department of Environmental Sciences, Western Norway University of Environmental Science, Sogndal, Norway
| | | | - Aliyah R Debbonaire
- Department of Life Sciences, Cledwyn Building, Aberystwyth University, Wales, UK
| | - Nozomu Takeuchi
- Department of Earth Sciences, Graduate School of Science, Chiba University, Chiba, Japan
| | - Arwyn Edwards
- Department of Life Sciences, Cledwyn Building, Aberystwyth University, Wales, UK
- Department of Arctic Biology, University Centre in Svalbard (UNIS), Longyearbyen, Svalbard, Norway
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4
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Lu M, Luo X, Jiao JJ, Li H, Kuang X, Wang X, Feng Y, Zheng C. Uncovering the processes of microbial community assembly in the near-surface sediments of a climate-sensitive glacier-fed lake. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 345:118714. [PMID: 37542806 DOI: 10.1016/j.jenvman.2023.118714] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Revised: 07/09/2023] [Accepted: 07/26/2023] [Indexed: 08/07/2023]
Abstract
Glacier-fed lakes are characterized by cold temperatures, high altitudes, and nutrient-poor conditions. Despite these challenging conditions, near-surface sediments of glacier-fed lakes harbor rich microbial communities that are critical for ecosystem functioning and serve as a bridge between aquatic ecology and the deep subsurface biosphere. However, there is limited knowledge regarding the microbial communities and their assembly processes in these sediments, which are highly vulnerable to climate change. To fill this knowledge gap, this study systematically analyzed environmental variables, microbial communities, diversity, co-occurrence relationships, and community assembly processes in the near-surface sediments of a glacier-fed lake in the Tibetan Plateau. The results revealed distinct vertical gradients in microbial diversity and subcommunities, highlighting the significant influence of selection processes and adaptive abilities on microbial communities. Specifically, specialists played a crucial role within the overall microbial communities. Microbial assembly was primarily driven by homogeneous selection, but its influence declined with increasing depth. In contrast, homogenizing dispersal showed an opposite pattern, and the bottom layer exhibited heterogeneous selection and undominated processes. These patterns of microbial assembly were primarily driven by environmental gradients, with significant contributions from processes associated to ammonium and organic matter deposition, as well as chemical precipitation in response to a warming climate. This study enhances our understanding of the microbial communities and assembly processes in the near-surface sediments of glacier-fed lakes and sheds light on geo-microbiological processes in climate-sensitive lacustrine sediments.
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Affiliation(s)
- Meiqing Lu
- Department of Earth Sciences, The University of Hong Kong, Hong Kong, China; School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Xin Luo
- Department of Earth Sciences, The University of Hong Kong, Hong Kong, China
| | - Jiu Jimmy Jiao
- Department of Earth Sciences, The University of Hong Kong, Hong Kong, China.
| | - Hailong Li
- School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen, 518055, China; Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Xingxing Kuang
- School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen, 518055, China; Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Xuejing Wang
- School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen, 518055, China; Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Yuqing Feng
- School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen, 518055, China; Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Chunmiao Zheng
- School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen, 518055, China; Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control, Southern University of Science and Technology, Shenzhen, 518055, China
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Zhang C, Ren Z. The role of subsurface ice in sustaining bacteria in continental and maritime glaciers. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 896:165324. [PMID: 37414181 DOI: 10.1016/j.scitotenv.2023.165324] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Revised: 06/29/2023] [Accepted: 07/02/2023] [Indexed: 07/08/2023]
Abstract
In supraglacial environments, surface and subsurface ices are two distinct and connected microhabitats in terms of physicochemical and biological aspects. At the frontline of climate change, glaciers lose tremendous ice masses to downstream ecosystems, serving as crucial sources of both biotic and abiotic materials. In this study, we studied the disparities and relationships of microbial communities between surface and subsurface ices collected from a maritime and a continental glacier during summer. The results showed that surface ices had significantly higher nutrients and were more physiochemically different than subsurface ices. Despite lower nutrients, subsurface ices had higher alpha-diversity with more unique and enriched operational taxonomic units (OTUs) than surface ices, indicating the potential role of subsurface as a bacterial refuge. Sorensen dissimilarity between bacterial communities in surface ices and subsurface ices was mainly contributed by the turnover component, suggesting strong species replacement from surface to subsurface ices due to large environmental gradients. For different glaciers, the maritime glacier had significantly higher alpha-diversity than the continental glacier. The difference between surface and subsurface communities was more pronounced in the maritime glacier than in the continental glacier. The network analysis revealed that surface-enriched and subsurface-enriched OTUs formed independent modules, with surface-enriched OTUs having closer interconnections and greater importance in the network of the maritime glacier. This study highlights the important role of subsurface ice as a bacterial refuge and enriches our knowledge of microbial properties in glaciers.
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Affiliation(s)
- Cheng Zhang
- School of Engineering Technology, Beijing Normal University, Zhuhai, China; Instrumentation and Service Center for Science and Technology, Beijing Normal University, Zhuhai, China
| | - Ze Ren
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China.
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6
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Broadwell ELM, Pickford RE, Perkins RG, Sgouridis F, Williamson CJ. Adaptation versus plastic responses to temperature, light, and nitrate availability in cultured snow algal strains. FEMS Microbiol Ecol 2023; 99:fiad088. [PMID: 37553143 PMCID: PMC10481995 DOI: 10.1093/femsec/fiad088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 06/29/2023] [Accepted: 08/07/2023] [Indexed: 08/10/2023] Open
Abstract
Snow algal blooms are widespread, dominating low temperature, high light, and oligotrophic melting snowpacks. Here, we assessed the photophysiological and cellular stoichiometric responses of snow algal genera Chloromonas spp. and Microglena spp. in their vegetative life stage isolated from the Arctic and Antarctic to gradients in temperature (5 - 15°C), nitrate availability (1 - 10 µmol L-1), and light (50 and 500 µmol photons m-2 s-1). When grown under gradients in temperature, measured snow algal strains displayed Fv/Fm values increased by ∼115% and electron transport rates decreased by ∼50% at 5°C compared to 10 and 15°C, demonstrating how low temperatures can mimic high light impacts to photophysiology. When using carrying capacity as opposed to growth rate as a metric for determining the temperature optima, these snow algal strains can be defined as psychrophilic, with carrying capacities ∼90% higher at 5°C than warmer temperatures. All strains approached Redfield C:N stoichiometry when cultured under nutrient replete conditions regardless of temperature (5.7 ± 0.4 across all strains), whereas significant increases in C:N were apparent when strains were cultured under nitrate concentrations that reflected in situ conditions (17.8 ± 5.9). Intra-specific responses in photophysiology were apparent under high light with Chloromonas spp. more capable of acclimating to higher light intensities. These findings suggest that in situ conditions are not optimal for the studied snow algal strains, but they are able to dynamically adjust both their photochemistry and stoichiometry to acclimate to these conditions.
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Affiliation(s)
- Emily L M Broadwell
- School of Geographical Sciences, University of Bristol, University Road, Bristol, BS8 1SS, United Kingdom
| | - Rachel E Pickford
- School of Geographical Sciences, University of Bristol, University Road, Bristol, BS8 1SS, United Kingdom
| | - Rupert G Perkins
- School of Earth and Environmental Sciences, Cardiff University, Main Building, Park Place, Cardiff, CF10 3AT, United Kingdom
| | - Fotis Sgouridis
- School of Geographical Sciences, University of Bristol, University Road, Bristol, BS8 1SS, United Kingdom
| | - Christopher J Williamson
- School of Geographical Sciences, University of Bristol, University Road, Bristol, BS8 1SS, United Kingdom
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Hotaling S, Price TL, Hamilton TL. Summer Dynamics of Microbial Diversity on a Mountain Glacier. mSphere 2022; 7:e0050322. [PMID: 36342146 PMCID: PMC9769511 DOI: 10.1128/msphere.00503-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Accepted: 10/23/2022] [Indexed: 11/09/2022] Open
Abstract
Glaciers are rapidly receding under climate change. A melting cryosphere will dramatically alter global sea levels, carbon cycling, and water resource availability. Glaciers host rich biotic communities that are dominated by microbial diversity, and this biodiversity can impact surface albedo, thereby driving a feedback loop between biodiversity and cryosphere melt. However, the microbial diversity of glacier ecosystems remains largely unknown outside of major ice sheets, particularly from a temporal perspective. Here, we characterized temporal dynamics of bacteria, eukaryotes, and algae on the Paradise Glacier, Mount Rainier, USA, over nine time points spanning the summer melt season. During our study, the glacier surface steadily darkened as seasonal snow melted and darkening agents accumulated until new snow fell in late September. From a community-wide perspective, the bacterial community remained generally constant while eukaryotes and algae exhibited temporal progression and community turnover. Patterns of individual taxonomic groups, however, were highly stochastic. We found little support for our a priori prediction that autotroph abundance would peak before heterotrophs. Notably, two different trends in snow algae emerged-an abundant early- and late-season operational taxonomic unit (OTU) with a different midsummer OTU that peaked in August. Overall, our results highlight the need for temporal sampling to clarify microbial diversity on glaciers and that caution should be exercised when interpreting results from single or few time points. IMPORTANCE Microbial diversity on mountain glaciers is an underexplored component of global biodiversity. Microbial presence and activity can also reduce the surface albedo or reflectiveness of glaciers, causing them to absorb more solar radiation and melt faster, which in turn drives more microbial activity. To date, most explorations of microbial diversity in the mountain cryosphere have only included single time points or focused on one microbial community (e.g., bacteria). Here, we performed temporal sampling over a summer melt season for the full microbial community, including bacteria, eukaryotes, and fungi, on the Paradise Glacier, Washington, USA. Over the summer, the bacterial community remained generally constant, whereas eukaryote and algal communities temporally changed through the melt season. Individual taxonomic groups, however, exhibited considerable stochasticity. Overall, our results highlight the need for temporal sampling on glaciers and that caution should be exercised when interpreting results from single or few time points.
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Affiliation(s)
- Scott Hotaling
- Department of Watershed Sciences, Utah State University, Logan, Utah, USA
| | - Taylor L. Price
- Department of Plant and Microbial Biology and the BioTechnology Institute, University of Minnesota, Saint Paul, Minnesota, USA
| | - Trinity L. Hamilton
- Department of Plant and Microbial Biology and the BioTechnology Institute, University of Minnesota, Saint Paul, Minnesota, USA
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Ren Z, Jia X, Zhang Y, Ma K, Zhang C, Li X. Biogeography and environmental drivers of zooplankton communities in permafrost-affected lakes on the Qinghai-Tibet Plateau. Glob Ecol Conserv 2022. [DOI: 10.1016/j.gecco.2022.e02191] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
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9
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Lyons R, Weatherly S, Waters J, Bentley J. Thermodynamics Affecting Glacier-Released 4-Nonylphenol Deposition in Alaska, USA. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2022; 41:1623-1636. [PMID: 35404492 PMCID: PMC9324835 DOI: 10.1002/etc.5343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 10/11/2021] [Accepted: 04/07/2022] [Indexed: 05/15/2023]
Abstract
Glaciers have recently been recognized as a secondary source of organic pollutants. As glacier melt rates increase, downstream ecosystems are at increasing risk of exposure to these pollutants. Nonylphenols (NPs) are well-documented anthropogenic persistent pollutants whose environmental prevalence and ecotoxicity make them of immediate concern to the health of humans and wildlife populations. As glacier melt increases, transport of NPs to downstream environments will also increase. Snow, ice, meltwater, and till for five glaciers in the Chugach National Forest and Kenai Fjords National Park, Alaska, USA, were investigated for the presence of 4-nonylphenol (4NP). Average concentrations for snow, ice, meltwater, and glacial till were 0.77 ± .017 µg/L snow water, 0.75 ± .006 µg/L, 0.26 ± .053 µg/L, and 0.016 ± .004 µg/g, respectively. All samples showed the presence of 4NP. Deposition of 4NP downstream from glaciers will depend more on the ionic strength of the water than organic carbon to drive partitioning and deposition. Laboratory studies of partition coefficients showed that ionic strength contributed 59% of the driving force behind partitioning, while organic carbon contributed 36%. Evidence was found for interaction between organic carbon and the aqueous phase. The 4NP Setschenow constants (Ks ) were determined for particle types with varying percentages of organic carbon. Values of Ks increased with the percentage of organic carbon. These relationships will shape further studies of 4NP deposition into the environment downstream of glacier outflow. Environ Toxicol Chem 2022;41:1623-1636. © The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.
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Affiliation(s)
- Rebecca Lyons
- Department of Chemistry, College of Arts and SciencesUniversity of RedlandsRedlandsCaliforniaUSA
| | - Shaun Weatherly
- Department of Chemistry, College of Arts and SciencesUniversity of RedlandsRedlandsCaliforniaUSA
| | - Jason Waters
- Department of Chemistry, College of Arts and SciencesUniversity of RedlandsRedlandsCaliforniaUSA
| | - Jim Bentley
- Department of Chemistry, College of Arts and SciencesUniversity of RedlandsRedlandsCaliforniaUSA
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Kleinteich J, Hanselmann K, Hildebrand F, Kappler A, Zarfl C. Glacier melt-down changes habitat characteristics and unique microbial community composition and physiology in Alpine lakes sediments. FEMS Microbiol Ecol 2022; 98:6617590. [PMID: 35749563 DOI: 10.1093/femsec/fiac075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2022] [Revised: 04/27/2022] [Accepted: 06/20/2022] [Indexed: 11/13/2022] Open
Abstract
Glacial melt-down alters hydrological and physicochemical conditions in downstream aquatic habitats. In this study we tested if sediment associated microbial communities respond to the decrease of glaciers and associated meltwater flows in high-alpine lakes. We analysed 16 lakes in forefield catchments of three glaciers in the Eastern Swiss Alps on physicochemical and biological parameters. We compared lakes fed by glacier meltwater with hydrologically disconnected lakes, as well as "mixed" lakes that received water from both other lake types. Glacier-fed lakes had a higher turbidity (94 NTU) and conductivity (47 µS/cm), but were up to 5.2°C colder than disconnected lakes (1.5 NTU, 26 µS/cm). Nutrient concentration was low in all lakes (TN <0.05 mg/L, TP <0.02 mg/L). Bacterial diversity in the sediments decreased significantly with altitude. Bacterial community composition correlated with turbidity, temperature, conductivity, nitrate and lake age and was distinctly different between glacier-fed compared to disconnected and mixed water lakes, but not between catchments. Chemoheterotrophic processes were more abundant in glacier-fed compared to disconnected and mixed water lakes where photoautotrophic processes dominated. Our study suggests that the loss of glaciers will change sediment bacterial community composition and physiology that are unique for glacier-fed lakes in mountain and polar regions.
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Affiliation(s)
- Julia Kleinteich
- Center for Applied Geoscience, Eberhard Karls University of Tübingen, Germany
| | - Kurt Hanselmann
- Department of Earth Sciences, Swiss Federal Institute of Technology (ETH) Zurich, Switzerland
| | - Falk Hildebrand
- Earlham Institute, Norwich Research Park, Norwich, Norfolk, NR4 7UZ, UK.,Gut Microbes & Health, Quadram Institute Bioscience, Norwich Research Park, Norwich, Norfolk, NR4 7UQ, UK
| | - Andreas Kappler
- Center for Applied Geoscience, Eberhard Karls University of Tübingen, Germany.,Cluster of Excellence: EXC 2124: Controlling Microbes to Fight Infection, Tübingen, Germany
| | - Christiane Zarfl
- Center for Applied Geoscience, Eberhard Karls University of Tübingen, Germany
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11
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Rathore M, Sinha RK, Venkatachalam S, Krishnan KP. Microbial diversity and associated metabolic potential in the supraglacial habitat of a fast-retreating glacier: a case study of Patsio glacier, North-western Himalaya. ENVIRONMENTAL MICROBIOLOGY REPORTS 2022; 14:443-452. [PMID: 34664398 DOI: 10.1111/1758-2229.13017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Accepted: 10/07/2021] [Indexed: 06/13/2023]
Abstract
In the present study, we investigated the microbial community composition and their associated metabolic potentials using the 16S rRNA gene (V3-V4) and ITS (ITS1) amplicon sequencing approach in the Patsio glacier. The bacterial community composition was mainly dominated by Bacteroidota (18%-38% of total reads) and Cyanobacteria (9%-30%), along with a rare Candidate phylum Patescibacteria. Ferruginibacter (13%) and Polaromonas (8%) were the most dominant genera identified across the samples known to have potential ecological roles in colonization, driving the functioning of supraglacial habitats. The prevalence of metabolic genes associated with nitrogen, carbon and sulfur cycling processes was identified in the present study. The fungal diversity was dominated by members of unclassified phyla, followed by Ascomycota (up to 6%) and Basidiomycota (up to 4%), in terms of its relative abundance. The relative abundance of Fusarium and Didymella (8%-14%) was higher among the high altitude, cryoconite samples (P1-P5), while Rhodotorula (12%-29%) dominated in the glacial ice debris samples (P6-P8). Thus, our study provides significant insights into dynamics of microbial communities and its potential ecological roles in the changing climate.
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Affiliation(s)
- Meena Rathore
- Arctic Ecology and Biogeochemistry Division, National Centre for Polar and Ocean Research, Ministry of Earth Sciences, Headland Sada, Vasco da Gama, Goa, India
- Department of Microbiology, Goa University, Taleigao Plateau, Goa, India
| | - Rupesh Kumar Sinha
- Arctic Ecology and Biogeochemistry Division, National Centre for Polar and Ocean Research, Ministry of Earth Sciences, Headland Sada, Vasco da Gama, Goa, India
| | - Siddarthan Venkatachalam
- Arctic Ecology and Biogeochemistry Division, National Centre for Polar and Ocean Research, Ministry of Earth Sciences, Headland Sada, Vasco da Gama, Goa, India
| | - Kottekkattu Padinchati Krishnan
- Arctic Ecology and Biogeochemistry Division, National Centre for Polar and Ocean Research, Ministry of Earth Sciences, Headland Sada, Vasco da Gama, Goa, India
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12
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Kohler TJ, Fodelianakis S, Michoud G, Ezzat L, Bourquin M, Peter H, Busi SB, Pramateftaki P, Deluigi N, Styllas M, Tolosano M, de Staercke V, Schön M, Brandani J, Marasco R, Daffonchio D, Wilmes P, Battin TJ. Glacier shrinkage will accelerate downstream decomposition of organic matter and alters microbiome structure and function. GLOBAL CHANGE BIOLOGY 2022; 28:3846-3859. [PMID: 35320603 PMCID: PMC9323552 DOI: 10.1111/gcb.16169] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Accepted: 03/06/2022] [Indexed: 05/22/2023]
Abstract
The shrinking of glaciers is among the most iconic consequences of climate change. Despite this, the downstream consequences for ecosystem processes and related microbiome structure and function remain poorly understood. Here, using a space-for-time substitution approach across 101 glacier-fed streams (GFSs) from six major regions worldwide, we investigated how glacier shrinkage is likely to impact the organic matter (OM) decomposition rates of benthic biofilms. To do this, we measured the activities of five common extracellular enzymes and estimated decomposition rates by using enzyme allocation equations based on stoichiometry. We found decomposition rates to average 0.0129 (% d-1 ), and that decreases in glacier influence (estimated by percent glacier catchment coverage, turbidity, and a glacier index) accelerates decomposition rates. To explore mechanisms behind these relationships, we further compared decomposition rates with biofilm and stream water characteristics. We found that chlorophyll-a, temperature, and stream water N:P together explained 61% of the variability in decomposition. Algal biomass, which is also increasing with glacier shrinkage, showed a particularly strong relationship with decomposition, likely indicating their importance in contributing labile organic compounds to these carbon-poor habitats. We also found high relative abundances of chytrid fungi in GFS sediments, which putatively parasitize these algae, promoting decomposition through a fungal shunt. Exploring the biofilm microbiome, we then sought to identify bacterial phylogenetic clades significantly associated with decomposition, and found numerous positively (e.g., Saprospiraceae) and negatively (e.g., Nitrospira) related clades. Lastly, using metagenomics, we found evidence of different bacterial classes possessing different proportions of EEA-encoding genes, potentially informing some of the microbial associations with decomposition rates. Our results, therefore, present new mechanistic insights into OM decomposition in GFSs by demonstrating that an algal-based "green food web" is likely to increase in importance in the future and will promote important biogeochemical shifts in these streams as glaciers vanish.
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Affiliation(s)
- Tyler J. Kohler
- River Ecosystems Laboratory, Alpine and Polar Environmental Research Center, Ecole Polytechnique Fédérale de Lausanne (EPFL)LausanneSwitzerland
| | - Stilianos Fodelianakis
- River Ecosystems Laboratory, Alpine and Polar Environmental Research Center, Ecole Polytechnique Fédérale de Lausanne (EPFL)LausanneSwitzerland
| | - Grégoire Michoud
- River Ecosystems Laboratory, Alpine and Polar Environmental Research Center, Ecole Polytechnique Fédérale de Lausanne (EPFL)LausanneSwitzerland
| | - Leïla Ezzat
- River Ecosystems Laboratory, Alpine and Polar Environmental Research Center, Ecole Polytechnique Fédérale de Lausanne (EPFL)LausanneSwitzerland
| | - Massimo Bourquin
- River Ecosystems Laboratory, Alpine and Polar Environmental Research Center, Ecole Polytechnique Fédérale de Lausanne (EPFL)LausanneSwitzerland
| | - Hannes Peter
- River Ecosystems Laboratory, Alpine and Polar Environmental Research Center, Ecole Polytechnique Fédérale de Lausanne (EPFL)LausanneSwitzerland
| | - Susheel Bhanu Busi
- Systems Ecology Research GroupLuxembourg Centre for Systems BiomedicineUniversity of LuxembourgEsch‐sur‐AlzetteLuxembourg
| | - Paraskevi Pramateftaki
- River Ecosystems Laboratory, Alpine and Polar Environmental Research Center, Ecole Polytechnique Fédérale de Lausanne (EPFL)LausanneSwitzerland
| | - Nicola Deluigi
- River Ecosystems Laboratory, Alpine and Polar Environmental Research Center, Ecole Polytechnique Fédérale de Lausanne (EPFL)LausanneSwitzerland
| | - Michail Styllas
- River Ecosystems Laboratory, Alpine and Polar Environmental Research Center, Ecole Polytechnique Fédérale de Lausanne (EPFL)LausanneSwitzerland
| | - Matteo Tolosano
- River Ecosystems Laboratory, Alpine and Polar Environmental Research Center, Ecole Polytechnique Fédérale de Lausanne (EPFL)LausanneSwitzerland
| | - Vincent de Staercke
- River Ecosystems Laboratory, Alpine and Polar Environmental Research Center, Ecole Polytechnique Fédérale de Lausanne (EPFL)LausanneSwitzerland
| | - Martina Schön
- River Ecosystems Laboratory, Alpine and Polar Environmental Research Center, Ecole Polytechnique Fédérale de Lausanne (EPFL)LausanneSwitzerland
| | - Jade Brandani
- River Ecosystems Laboratory, Alpine and Polar Environmental Research Center, Ecole Polytechnique Fédérale de Lausanne (EPFL)LausanneSwitzerland
| | - Ramona Marasco
- Biological and Environmental Sciences and Engineering Division (BESE)King Abdullah University of Science and Technology (KAUST)ThuwalSaudi Arabia
| | - Daniele Daffonchio
- Biological and Environmental Sciences and Engineering Division (BESE)King Abdullah University of Science and Technology (KAUST)ThuwalSaudi Arabia
| | - Paul Wilmes
- Systems Ecology Research GroupLuxembourg Centre for Systems BiomedicineUniversity of LuxembourgEsch‐sur‐AlzetteLuxembourg
| | - Tom J. Battin
- River Ecosystems Laboratory, Alpine and Polar Environmental Research Center, Ecole Polytechnique Fédérale de Lausanne (EPFL)LausanneSwitzerland
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13
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Ren Z, Gao H, Luo W, Elser JJ. Bacterial communities in surface and basal ice of a glacier terminus in the headwaters of Yangtze River on the Qinghai-Tibet Plateau. ENVIRONMENTAL MICROBIOME 2022; 17:12. [PMID: 35346386 PMCID: PMC8962558 DOI: 10.1186/s40793-022-00408-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/07/2021] [Accepted: 03/13/2022] [Indexed: 06/14/2023]
Abstract
BACKGROUND On the front lines of climate change, glacier termini play crucial roles in linking glaciers and downstream ecosystems during glacier retreat. However, we lack a clear understanding of biological processes that occur in surface and basal ice at glacier termini. METHODS Here, we studied the bacterial communities in surface ice and basal ice (the bottom layer) of a glacier terminus in the Yangtze River Source, Qinghai-Tibet Plateau. RESULTS Surface and basal ice harbored distinct bacterial communities but shared some core taxa. Surface ice communities had a higher α-diversity than those in basal ice and were dominated by Proteobacteria, Firmicutes, Bacteroidetes, Actinobacteria, and Cyanobacteria while basal ice was dominated by Firmicutes and Proteobacteria. The bacterial communities were also substantially different in functional potential. Genes associated with functional categories of cellular processes and metabolism were significantly enriched in surface ice, while genes connected to environmental information processing were enriched in basal ice. In terms of biogeochemical cycles of carbon, nitrogen, phosphorus, and sulfur, bacterial communities in surface ice were enriched for genes connected to aerobic carbon fixation, aerobic respiration, denitrification, nitrogen assimilation, nitrogen mineralization, sulfur mineralization, alkaline phosphatase, and polyphosphate kinase. In contrast, bacterial communities in basal ice were enriched for genes involved in anaerobic carbon fixation, fermentation, nitrate reduction, 2-aminoethylphosphonic acid pathway, G3P transporter, glycerophosphodiester phosphodiesterase, and exopolyphosphatase. Structural equation modeling showed that total nitrogen and environmental carbon:phosphorus were positively while environmental nitrogen:phosphorus was negatively associated with taxonomic β-diversity which itself was strongly associated with functional β-diversity of bacterial communities. CONCLUSIONS This study furthers our understanding of biogeochemical cycling of the mountain cryosphere by revealing the genetic potential of the bacterial communities in surface and basal ice at the glacier terminus, providing new insights into glacial ecology as well as the influences of glacier retreat on downstream systems.
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Affiliation(s)
- Ze Ren
- Advanced Institute of Natural Sciences, Beijing Normal University, Zhuhai, 519087, China.
- School of Environment, Beijing Normal University, Beijing, 100875, China.
| | - Hongkai Gao
- Key Laboratory of Geographic Information Science (Ministry of Education), East China Normal University, Shanghai, 200241, China.
- School of Geographic Sciences, East China Normal University, Shanghai, 200241, China.
| | - Wei Luo
- Polar Research Institute of China, Ministry of Natural Resources, Shanghai, 200136, China
- School of Oceanography, Shanghai Jiao Tong University, Shanghai, 200030, China
| | - James J Elser
- Flathead Lake Biological Station, University of Montana, Polson, 59860, USA
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14
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Fillinger L, Hürkamp K, Stumpp C, Weber N, Forster D, Hausmann B, Schultz L, Griebler C. Spatial and Annual Variation in Microbial Abundance, Community Composition, and Diversity Associated With Alpine Surface Snow. Front Microbiol 2021; 12:781904. [PMID: 34912321 PMCID: PMC8667604 DOI: 10.3389/fmicb.2021.781904] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Accepted: 11/08/2021] [Indexed: 01/04/2023] Open
Abstract
Understanding microbial community dynamics in the alpine cryosphere is an important step toward assessing climate change impacts on these fragile ecosystems and meltwater-fed environments downstream. In this study, we analyzed microbial community composition, variation in community alpha and beta diversity, and the number of prokaryotic cells and virus-like particles (VLP) in seasonal snowpack from two consecutive years at three high altitude mountain summits along a longitudinal transect across the European Alps. Numbers of prokaryotic cells and VLP both ranged around 104 and 105 per mL of snow meltwater on average, with variation generally within one order of magnitude between sites and years. VLP-to-prokaryotic cell ratios spanned two orders of magnitude, with median values close to 1, and little variation between sites and years in the majority of cases. Estimates of microbial community alpha diversity inferred from Hill numbers revealed low contributions of common and abundant microbial taxa to the total taxon richness, and thus low community evenness. Similar to prokaryotic cell and VLP numbers, differences in alpha diversity between years and sites were generally relatively modest. In contrast, community composition displayed strong variation between sites and especially between years. Analyses of taxonomic and phylogenetic community composition showed that differences between sites within years were mainly characterized by changes in abundances of microbial taxa from similar phylogenetic clades, whereas shifts between years were due to significant phylogenetic turnover. Our findings on the spatiotemporal dynamics and magnitude of variation of microbial abundances, community diversity, and composition in surface snow may help define baseline levels to assess future impacts of climate change on the alpine cryosphere.
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Affiliation(s)
- Lucas Fillinger
- Department of Functional and Evolutionary Ecology, University of Vienna, Vienna, Austria
| | - Kerstin Hürkamp
- Institute of Radiation Medicine, Helmholtz Zentrum München, Neuherberg, Germany
| | - Christine Stumpp
- Institute of Groundwater Ecology, Helmholtz Zentrum München, Neuherberg, Germany
| | - Nina Weber
- Institute of Groundwater Ecology, Helmholtz Zentrum München, Neuherberg, Germany
| | - Dominik Forster
- Institute of Groundwater Ecology, Helmholtz Zentrum München, Neuherberg, Germany
| | - Bela Hausmann
- Joint Microbiome Facility of the Medical University of Vienna and the University of Vienna, Vienna, Austria
- Department of Laboratory Medicine, Medical University of Vienna, Vienna, Austria
| | - Lotta Schultz
- Department of Functional and Evolutionary Ecology, University of Vienna, Vienna, Austria
| | - Christian Griebler
- Institute of Groundwater Ecology, Helmholtz Zentrum München, Neuherberg, Germany
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15
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Clark SC, Barnes RT, Oleksy IA, Baron JS, Hastings MG. Persistent Nitrate in Alpine Waters with Changing Atmospheric Deposition and Warming Trends. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:14946-14956. [PMID: 34637308 DOI: 10.1021/acs.est.1c02515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Nitrate concentrations in high-elevation lakes of the Colorado Front Range remain elevated despite declining trends in atmospherically deposited nitrate since 2000. The current source of this elevated nitrate in surface waters remains elusive, given shifts in additional nitrogen sources via glacial inputs and atmospheric ammonium deposition. We present the complete isotopic composition of nitrate (δ15N, δ18O, and Δ17O) from a suite of nitrate-bearing source waters collected during the summers of 2017-2018 from two alpine ecosystems to constrain the provenance of elevated nitrate in surface waters during the summer open-water season. The results indicate a consistent contribution of uncycled atmospheric nitrate throughout the summer (13-23%) to alpine lakes, despite seasonal changes in source water inputs. The balance of nitrate (as high as 87% in late summer) is likely from nitrate production within the catchment via nitrification of reduced nitrogen sources (e.g., thawed soil organic matter and ammonium deposition) and released with rock glacier meltwater. The role of microbially produced nitrate has become increasingly important over time based on historical surface water samples from the mid-90s to present, a trend coincident with increasing ammonium deposition to alpine systems.
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Affiliation(s)
- Sydney C Clark
- Department of Earth, Environmental, and Planetary Sciences, Brown University, Providence, Rhode Island 02912, United States
- Institute at Brown for Environment and Society, Brown University, Providence, Rhode Island 02912, United States
| | - Rebecca T Barnes
- The Environmental Studies Program, Colorado College, Colorado Springs, Colorado 80903, United States
| | - Isabella A Oleksy
- Department of Zoology and Physiology, University of Wyoming, Laramie, Wyoming 82071, United States
| | - Jill S Baron
- U.S. Geological Survey, Fort Collins, Colorado 80523, United States
| | - Meredith G Hastings
- Department of Earth, Environmental, and Planetary Sciences, Brown University, Providence, Rhode Island 02912, United States
- Institute at Brown for Environment and Society, Brown University, Providence, Rhode Island 02912, United States
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16
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Temperature-induced changes in biofilm organic matter utilization in arctic streams (Disko Island, Greenland). Polar Biol 2021. [DOI: 10.1007/s00300-021-02955-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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17
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Liu K, Liu Y, Hu A, Wang F, Zhang Z, Yan Q, Ji M, Vick-Majors TJ. Fate of glacier surface snow-originating bacteria in the glacier-fed hydrologic continuums. Environ Microbiol 2021; 23:6450-6462. [PMID: 34559463 DOI: 10.1111/1462-2920.15788] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 09/22/2021] [Indexed: 11/28/2022]
Abstract
Glaciers represent important biomes of Earth and are recognized as key species pools for downstream aquatic environments. Worldwide, rapidly receding glaciers are driving shifts in hydrology, species distributions and threatening microbial diversity in glacier-fed aquatic ecosystems. However, the impact of glacier surface snow-originating taxa on the microbial diversity in downstream aquatic environments has been little explored. To elucidate the contribution of glacier surface snow-originating taxa to bacterial diversity in downstream aquatic environments, we collected samples from glacier surface snows, downstream streams and lakes along three glacier-fed hydrologic continuums on the Tibetan Plateau. Our results showed that glacier stream acts as recipients and vectors of bacteria originating from the glacier environments. The contributions of glacier surface snow-originating taxa to downstream bacterial communities decrease from the streams to lakes, which was consistently observed in three geographically separated glacier-fed ecosystems. Our results also revealed that some rare snow-originating bacteria can thrive along the hydrologic continuums and become dominant in downstream habitats. Finally, our results indicated that the dispersal patterns of bacterial communities are largely determined by mass effects and increasingly subjected to local sorting of species along the glacier-fed hydrologic continuums. Collectively, this study provides insights into the fate of bacterial assemblages in glacier surface snow following snow melt and how bacterial communities in aquatic environments are affected by the influx of glacier snow-originating bacteria.
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Affiliation(s)
- Keshao Liu
- State Key Laboratory of Tibetan Plateau Earth System Science (LATPES), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China
| | - Yongqin Liu
- State Key Laboratory of Tibetan Plateau Earth System Science (LATPES), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China.,Center for the Pan-Third Pole Environment, Lanzhou University, Lanzhou, 730000, China
| | - Anyi Hu
- Key Laboratory of Urban Pollutant Conversion, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, China
| | - Feng Wang
- State Key Laboratory of Tibetan Plateau Earth System Science (LATPES), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China
| | - Zhihao Zhang
- State Key Laboratory of Tibetan Plateau Earth System Science (LATPES), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China
| | - Qi Yan
- Center for the Pan-Third Pole Environment, Lanzhou University, Lanzhou, 730000, China
| | - Mukan Ji
- Center for the Pan-Third Pole Environment, Lanzhou University, Lanzhou, 730000, China
| | - Trista J Vick-Majors
- Department of Biological Sciences, Michigan Technological University, Houghton, MI, USA
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18
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Brahney J, Bothwell ML, Capito L, Gray CA, Null SE, Menounos B, Curtis PJ. Glacier recession alters stream water quality characteristics facilitating bloom formation in the benthic diatom Didymosphenia geminata. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 764:142856. [PMID: 33092829 DOI: 10.1016/j.scitotenv.2020.142856] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Revised: 09/17/2020] [Accepted: 10/02/2020] [Indexed: 06/11/2023]
Abstract
Glaciers provide cold, turbid runoff to many mountain streams in the late summer and buffer against years with low snowfall. The input of glacial meltwater to streams maintains unique habitats and support a diversity of stream flora and fauna. In western Canada, glaciers are anticipated to retreat by 60-80% by the end of the century, and this retreat will invoke widespread changes in mountain ecosystems. We used a space-for-time substitution along a gradient of glacierization in western Canada to develop insights into changes that may occur in glaciated regions over the coming decades. Here we report on observed changes in physical (temperature, turbidity), and chemical (dissolved and total nutrients) characteristics of mountain streams and the associated shifts in their diatom communities during de-glacierization. Shifts in habitat characteristics across gradients include changes in nutrient concentrations, light penetration, temperatures, and flow, all of which have led to distinct changes in diatom community composition. Importantly, glacial-fed rivers were 3-5 °C cooler than rivers without glacial contributions. Declines in glacial meltwater contribution to streams resulted in shifts in the timing of nutrient fluxes and lower concentrations of total phosphorus (TP), soluble reactive phosphorus (SRP), and higher dissolved inorganic nitrogen (DIN) and light penetration. The above set of conditions were linked to the overgrowth of the benthic diatom Didymosphenia geminata. These changes in stream condition and D. geminata colony development primarily occurred in streams with marginal (2-5%) to no glacier cover. Our data support a hypothesis that climate-induced changes in river hydrochemistry and physical condition lead to a phenological mismatch that favors D. geminata bloom development.
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Affiliation(s)
- J Brahney
- Department of Watershed Sciences, Utah State University, Logan, UT 84322, United States of America.
| | - M L Bothwell
- Department of Fisheries and Oceans, Pacific Biological Station, Nanaimo, BC V9T 6N7, Canada
| | - L Capito
- Department of Watershed Sciences, Utah State University, Logan, UT 84322, United States of America
| | - C A Gray
- Department of Wildland Resources, Utah State University, Logan, UT 84322, United States of America
| | - S E Null
- Department of Watershed Sciences, Utah State University, Logan, UT 84322, United States of America
| | - B Menounos
- Geography Program and Natural Resources and Environmental Studies Institute, University of Northern British Columbia, Prince George, BC V6T 1Z9, Canada
| | - P J Curtis
- Department of Earth, Environmental, and Geographic Sciences, University of British Columbia, Okanagan, BC V1V 1V7, Canada
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19
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Brighenti S, Hotaling S, Finn DS, Fountain AG, Hayashi M, Herbst D, Saros JE, Tronstad LM, Millar CI. Rock glaciers and related cold rocky landforms: Overlooked climate refugia for mountain biodiversity. GLOBAL CHANGE BIOLOGY 2021; 27:1504-1517. [PMID: 33404095 DOI: 10.1111/gcb.15510] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Accepted: 12/29/2020] [Indexed: 05/22/2023]
Abstract
Mountains are global biodiversity hotspots where cold environments and their associated ecological communities are threatened by climate warming. Considerable research attention has been devoted to understanding the ecological effects of alpine glacier and snowfield recession. However, much less attention has been given to identifying climate refugia in mountain ecosystems where present-day environmental conditions will be maintained, at least in the near-term, as other habitats change. Around the world, montane communities of microbes, animals, and plants live on, adjacent to, and downstream of rock glaciers and related cold rocky landforms (CRL). These geomorphological features have been overlooked in the ecological literature despite being extremely common in mountain ranges worldwide with a propensity to support cold and stable habitats for aquatic and terrestrial biodiversity. CRLs are less responsive to atmospheric warming than alpine glaciers and snowfields due to the insulating nature and thermal inertia of their debris cover paired with their internal ventilation patterns. Thus, CRLs are likely to remain on the landscape after adjacent glaciers and snowfields have melted, thereby providing longer-term cold habitat for biodiversity living on and downstream of them. Here, we show that CRLs will likely act as key climate refugia for terrestrial and aquatic biodiversity in mountain ecosystems, offer guidelines for incorporating CRLs into conservation practices, and identify areas for future research.
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Affiliation(s)
- Stefano Brighenti
- Faculty of Science and Technology, Free University of Bozen-Bolzano, Bolzano, Italy
| | - Scott Hotaling
- School of Biological Sciences, Washington State University, Pullman, WA, USA
| | - Debra S Finn
- Department of Biology, Missouri State University, Springfield, MO, USA
| | | | - Masaki Hayashi
- Department of Geoscience, University of Calgary, Calgary, AB, Canada
| | - David Herbst
- Sierra Nevada Aquatic Research Laboratory and Institute of Marine Sciences, University of California, Santa Cruz, CA, USA
| | - Jasmine E Saros
- School of Biology and Ecology, Climate Change Institute, University of Maine, Orono, ME, USA
| | - Lusha M Tronstad
- Wyoming Natural Diversity Database, University of Wyoming, Laramie, WY, USA
| | - Constance I Millar
- Pacific Southwest Research Station, USDA Forest Service, Albany, CA, USA
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20
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Gu Z, Liu K, Pedersen MW, Wang F, Chen Y, Zeng C, Liu Y. Community assembly processes underlying the temporal dynamics of glacial stream and lake bacterial communities. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 761:143178. [PMID: 33153747 DOI: 10.1016/j.scitotenv.2020.143178] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Revised: 10/10/2020] [Accepted: 10/10/2020] [Indexed: 06/11/2023]
Abstract
Community assembly processes are important in structuring aquatic microbial communities; however, the influence of these processes on the dynamics of bacterial communities in glacial streams and lakes remains largely unstudied. To investigate the assembly processes underlying the temporal variation of the bacterial community, we collected 50 water samples over five months in an ephemeral glacial stream and its downstream lake at the terminus of the Qiangyong glacier on the Tibetan Plateau. Using the V4 hypervariable region of the bacterial 16S rRNA gene combined with environmental measurements, such as water temperature, pH, total nitrogen (TN), dissolved organic carbon (DOC) and water conductivity, we found that temporal variation in the environmental factors promoted the shift in the proglacial stream and the lake bacterial communities. The quantification of ecological processes showed that the stream microbial communities were influenced by the ecological drift (40%) in June, then changed to homogeneous selection (40%) in July and variable selection (60%) in September, while the dynamic pattern of proglacial lake bacterioplankton was governed by homogeneous selection (≥ 50%) over the time. Overall, the dynamic of bacterial community in the proglacial stream and lake water is influenced by environmental factors, and the community composition assembly of the Qiangyong glacial stream and lake could be dynamic and primarily governed by deterministic processes.
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Affiliation(s)
- Zhengquan Gu
- Key Laboratory of Alpine Ecology, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Keshao Liu
- University of Chinese Academy of Sciences, Beijing 100049, China; CAS Center for Excellence in Tibetan Plateau Earth Sciences, Chinese Academy of Sciences, Beijing 100101, China; Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, 100101, China.
| | - Mikkel Winther Pedersen
- The Globe Institute, University of Copenhagen, Oester Voldgade 5-7, Copenhagen C 1350, Denmark
| | - Feng Wang
- Key Laboratory of Alpine Ecology, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yuying Chen
- Key Laboratory of Alpine Ecology, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Chen Zeng
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, 100101, China
| | - Yongqin Liu
- University of Chinese Academy of Sciences, Beijing 100049, China; CAS Center for Excellence in Tibetan Plateau Earth Sciences, Chinese Academy of Sciences, Beijing 100101, China; Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, 100101, China
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21
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Kohler TJ, Peter H, Fodelianakis S, Pramateftaki P, Styllas M, Tolosano M, de Staercke V, Schön M, Busi SB, Wilmes P, Washburne A, Battin TJ. Patterns and Drivers of Extracellular Enzyme Activity in New Zealand Glacier-Fed Streams. Front Microbiol 2020; 11:591465. [PMID: 33329472 PMCID: PMC7711088 DOI: 10.3389/fmicb.2020.591465] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Accepted: 10/27/2020] [Indexed: 11/17/2022] Open
Abstract
Glacier-fed streams (GFSs) exhibit near-freezing temperatures, variable flows, and often high turbidities. Currently, the rapid shrinkage of mountain glaciers is altering the delivery of meltwater, solutes, and particulate matter to GFSs, with unknown consequences for their ecology. Benthic biofilms dominate microbial life in GFSs, and play a major role in their biogeochemical cycling. Mineralization is likely an important process for microbes to meet elemental budgets in these systems due to commonly oligotrophic conditions, and extracellular enzymes retained within the biofilm enable the degradation of organic matter and acquisition of carbon (C), nitrogen (N), and phosphorus (P). The measurement and comparison of these extracellular enzyme activities (EEA) can in turn provide insight into microbial elemental acquisition effort relative to environmental availability. To better understand how benthic biofilm communities meet resource demands, and how this might shift as glaciers vanish under climate change, we investigated biofilm EEA in 20 GFSs varying in glacier influence from New Zealand’s Southern Alps. Using turbidity and distance to the glacier snout normalized for glacier size as proxies for glacier influence, we found that bacterial abundance (BA), chlorophyll a (Chl a), extracellular polymeric substances (EPS), and total EEA per gram of sediment increased with decreasing glacier influence. Yet, when normalized by BA, EPS decreased with decreasing glacier influence, Chl a still increased, and there was no relationship with total EEA. Based on EEA ratios, we found that the majority of GFS microbial communities were N-limited, with a few streams of different underlying bedrock geology exhibiting P-limitation. Cell-specific C-acquiring EEA was positively related to the ratio of Chl a to BA, presumably reflecting the utilization of algal exudates. Meanwhile, cell-specific N-acquiring EEA were positively correlated with the concentration of dissolved inorganic nitrogen (DIN), and both N- and P-acquiring EEA increased with greater cell-specific EPS. Overall, our results reveal greater glacier influence to be negatively related to GFS biofilm biomass parameters, and generally associated with greater microbial N demand. These results help to illuminate the ecology of GFS biofilms, along with their biogeochemical response to a shifting habitat template with ongoing climate change.
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Affiliation(s)
- Tyler J Kohler
- Stream Biofilm and Ecosystem Research Laboratory, School of Architecture, Civil and Environmental Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Hannes Peter
- Stream Biofilm and Ecosystem Research Laboratory, School of Architecture, Civil and Environmental Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Stilianos Fodelianakis
- Stream Biofilm and Ecosystem Research Laboratory, School of Architecture, Civil and Environmental Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Paraskevi Pramateftaki
- Stream Biofilm and Ecosystem Research Laboratory, School of Architecture, Civil and Environmental Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Michail Styllas
- Stream Biofilm and Ecosystem Research Laboratory, School of Architecture, Civil and Environmental Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Matteo Tolosano
- Stream Biofilm and Ecosystem Research Laboratory, School of Architecture, Civil and Environmental Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Vincent de Staercke
- Stream Biofilm and Ecosystem Research Laboratory, School of Architecture, Civil and Environmental Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Martina Schön
- Stream Biofilm and Ecosystem Research Laboratory, School of Architecture, Civil and Environmental Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Susheel Bhanu Busi
- Systems Ecology Research Group, Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | - Paul Wilmes
- Systems Ecology Research Group, Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | - Alex Washburne
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT, United States.,Selva Analytics, LLC, Bozeman, MT, United States
| | - Tom J Battin
- Stream Biofilm and Ecosystem Research Laboratory, School of Architecture, Civil and Environmental Engineering, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
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22
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Elser JJ, Wu C, González AL, Shain DH, Smith HJ, Sommaruga R, Williamson CE, Brahney J, Hotaling S, Vanderwall J, Yu J, Aizen V, Aizen E, Battin TJ, Camassa R, Feng X, Jiang H, Lu L, Qu JJ, Ren Z, Wen J, Wen L, Woods HA, Xiong X, Xu J, Yu G, Harper JT, Saros JE. Key rules of life and the fading cryosphere: Impacts in alpine lakes and streams. GLOBAL CHANGE BIOLOGY 2020; 26:6644-6656. [PMID: 32969121 DOI: 10.1111/gcb.15362] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 08/07/2020] [Accepted: 08/30/2020] [Indexed: 06/11/2023]
Abstract
Alpine regions are changing rapidly due to loss of snow and ice in response to ongoing climate change. While studies have documented ecological responses in alpine lakes and streams to these changes, our ability to predict such outcomes is limited. We propose that the application of fundamental rules of life can help develop necessary predictive frameworks. We focus on four key rules of life and their interactions: the temperature dependence of biotic processes from enzymes to evolution; the wavelength dependence of the effects of solar radiation on biological and ecological processes; the ramifications of the non-arbitrary elemental stoichiometry of life; and maximization of limiting resource use efficiency across scales. As the cryosphere melts and thaws, alpine lakes and streams will experience major changes in temperature regimes, absolute and relative inputs of solar radiation in ultraviolet and photosynthetically active radiation, and relative supplies of resources (e.g., carbon, nitrogen, and phosphorus), leading to nonlinear and interactive effects on particular biota, as well as on community and ecosystem properties. We propose that applying these key rules of life to cryosphere-influenced ecosystems will reduce uncertainties about the impacts of global change and help develop an integrated global view of rapidly changing alpine environments. However, doing so will require intensive interdisciplinary collaboration and international cooperation. More broadly, the alpine cryosphere is an example of a system where improving our understanding of mechanistic underpinnings of living systems might transform our ability to predict and mitigate the impacts of ongoing global change across the daunting scope of diversity in Earth's biota and environments.
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Affiliation(s)
- James J Elser
- Flathead Lake Biological Station, University of Montana, Polson, MT, USA
| | - Chenxi Wu
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Angélica L González
- Department of Biology & Center for Computational and Integrative Biology, Rutgers University, Camden, NJ, USA
| | - Daniel H Shain
- Department of Biology & Center for Computational and Integrative Biology, Rutgers University, Camden, NJ, USA
| | - Heidi J Smith
- Center for Biofilm Engineering, Montana State University, Bozeman, MT, USA
| | - Ruben Sommaruga
- Lake and Glacier Research Group, Department of Ecology, University of Innsbruck, Innsbruck, Austria
| | | | - Janice Brahney
- Department of Watershed Sciences, Utah State University, Logan, UT, USA
| | - Scott Hotaling
- School of Biological Sciences, Washington State University, Pullman, WA, USA
| | - Joseph Vanderwall
- Flathead Lake Biological Station, University of Montana, Polson, MT, USA
| | - Jinlei Yu
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Science, Nanjing, China
| | - Vladimir Aizen
- Department of Geography, University of Idaho, Moscow, ID, USA
| | - Elena Aizen
- Department of Geography, University of Idaho, Moscow, ID, USA
| | - Tom J Battin
- Stream Biofilm and Ecosystem Research Laboratory, School of Architecture, Civil and Environmental Engineering, Ecole Polytechnique Fédérale Lausanne, Lausanne, Switzerland
| | - Roberto Camassa
- Department of Mathematics, Carolina Center for Interdisciplinary Applied Mathematics, University of North Carolina, Chapel Hill, NC, USA
| | - Xiu Feng
- Key Laboratory of Aquatic Biodiversity and Conservation, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Hongchen Jiang
- State Key Lab of Biogeology and Environmental Geology, China University of Geosciences, Wuhan, China
| | - Lixin Lu
- Cooperative Institute for Research in the Atmosphere, Colorado State University, Fort Collins, CO, USA
| | - John J Qu
- Global Environment and Natural Resources Institute (GENRI) and Department of Geography and GeoInformation Science (GGS), George Mason University, Fairfax, VA, USA
| | - Ze Ren
- Flathead Lake Biological Station, University of Montana, Polson, MT, USA
| | - Jun Wen
- Sichuan Key Laboratory of Plateau Atmosphere and Environment, College of Atmospheric Sciences, Chengdu University of Information Technology, Chendu, China
| | - Lijuan Wen
- Key Laboratory of Land Surface Process and Climate Change in Cold and Arid Region, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, China
| | - H Arthur Woods
- Division of Biological Sciences, University of Montana, Missoula, MT, USA
| | - Xiong Xiong
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Jun Xu
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Gongliang Yu
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Joel T Harper
- Department of Geosciences, University of Montana, Missoula, MT, USA
| | - Jasmine E Saros
- School of Biology and Ecology, Climate Change Institute, University of Maine, Orono, ME, USA
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23
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Oleksy IA, Beck WS, Lammers RW, Steger CE, Wilson C, Christianson K, Vincent K, Johnson G, Johnson PTJ, Baron JS. The role of warm, dry summers and variation in snowpack on phytoplankton dynamics in mountain lakes. Ecology 2020; 101:e03132. [PMID: 32628277 PMCID: PMC7583380 DOI: 10.1002/ecy.3132] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Revised: 02/28/2020] [Accepted: 05/21/2020] [Indexed: 11/08/2022]
Abstract
Climate change is altering biogeochemical, metabolic, and ecological functions in lakes across the globe. Historically, mountain lakes in temperate regions have been unproductive because of brief ice-free seasons, a snowmelt-driven hydrograph, cold temperatures, and steep topography with low vegetation and soil cover. We tested the relative importance of winter and summer weather, watershed characteristics, and water chemistry as drivers of phytoplankton dynamics. Using boosted regression tree models for 28 mountain lakes in Colorado, we examined regional, intraseasonal, and interannual drivers of variability in chlorophyll a as a proxy for lake phytoplankton. Phytoplankton biomass was inversely related to the maximum snow water equivalent (SWE) of the previous winter, as others have found. However, even in years with average SWE, summer precipitation extremes and warming enhanced phytoplankton biomass. Peak seasonal phytoplankton biomass coincided with the warmest water temperatures and lowest nitrogen-to-phosphorus ratios. Although links between snowpack, lake temperature, nutrients, and organic-matter dynamics are increasingly recognized as critical drivers of change in high-elevation lakes, our results highlight the additional influence of summer conditions on lake productivity in response to ongoing changes in climate. Continued changes in the timing, type, and magnitude of precipitation in combination with other global-change drivers (e.g., nutrient deposition) will affect production in mountain lakes, potentially shifting these historically oligotrophic lakes toward new ecosystem states. Ultimately, a deeper understanding of these drivers and pattern at multiple scales will allow us to anticipate ecological consequences of global change better.
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Affiliation(s)
- Isabella A. Oleksy
- Natural Resource Ecology LaboratoryColorado State UniversityFort CollinsColorado80526USA
- Cary Institute of Ecosystem StudiesMillbrookNew York12545USA
| | - Whitney S. Beck
- Department of BiologyColorado State UniversityFort CollinsColorado80526USA
| | | | - Cara E. Steger
- Cary Institute of Ecosystem StudiesMillbrookNew York12545USA
| | - Codie Wilson
- Department of GeosciencesColorado State UniversityFort CollinsColorado80526USA
| | - Kyle Christianson
- Department of Fish, Wildlife, and Conservation BiologyColorado State UniversityFort CollinsColorado80526USA
| | - Kim Vincent
- Department of Ecology and Evolutionary BiologyUniversity of ColoradoBoulderColorado80309USA
| | - Gunnar Johnson
- Department of GeologyPortland State UniversityPortlandOregon97201USA
| | - Pieter T. J. Johnson
- Department of Ecology and Evolutionary BiologyUniversity of ColoradoBoulderColorado80309USA
| | - J. S. Baron
- Natural Resource Ecology LaboratoryColorado State UniversityFort CollinsColorado80526USA
- U.S. Geological SurveyFort CollinsColorado80526USA
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24
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Oleksy IA, Baron JS, Leavitt PR, Spaulding SA. Nutrients and warming interact to force mountain lakes into unprecedented ecological states. Proc Biol Sci 2020; 287:20200304. [PMID: 32635862 DOI: 10.1098/rspb.2020.0304] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
While deposition of reactive nitrogen (N) in the twentieth century has been strongly linked to changes in diatom assemblages in high-elevation lakes, pronounced and contemporaneous changes in other algal groups suggest additional drivers. We explored the origin and magnitude of changes in two mountain lakes from the end of the Little Ice Age at ca 1850, to ca 2010, using lake sediments. We found dramatic changes in algal community abundance and composition. While diatoms remain the most abundant photosynthetic organisms, concentrations of diatom pigments decreased while pigments representing chlorophytes increased 200-300% since ca 1950 and total algal biomass more than doubled. Some algal changes began ca 1900 but shifts in most sedimentary proxies accelerated ca 1950 commensurate with many human-caused changes to the Earth System. In addition to N deposition, aeolian dust deposition may have contributed phosphorus. Strong increases in summer air and surface water temperatures since 1983 have direct and indirect consequences for high-elevation ecosystems. Such warming could have directly enhanced nutrient use and primary production. Indirect consequences of warming include enhanced leaching of nutrients from geologic and cryosphere sources, particularly as glaciers ablate. While we infer causal mechanisms, changes in primary producer communities appear to be without historical precedent and are commensurate with the post-1950 acceleration of global change.
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Affiliation(s)
- Isabella A Oleksy
- Natural Resource Ecology Laboratory, Colorado State University, Fort Collins, CO 80523, USA.,Cary Institute of Ecosystem Studies, Millbrook, NY 12545, USA
| | - Jill S Baron
- Natural Resource Ecology Laboratory, Colorado State University, Fort Collins, CO 80523, USA.,U.S. Geological Survey, Fort Collins, CO 80526, USA
| | - Peter R Leavitt
- Institute of Environmental Change and Society, University of Regina, Regina, Saskatchewan, S4S 0A2 Canada.,Institute for Global Food Security, Queen's University Belfast, Belfast, Antrim BT9 5DL, UK
| | - Sarah A Spaulding
- U.S. Geological Survey/INSTAAR, University of Colorado, Boulder, CO, USA
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25
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Hotaling S, Wimberger PH, Kelley JL, Watts HE. Macroinvertebrates on glaciers: a key resource for terrestrial food webs? Ecology 2020; 101:e02947. [DOI: 10.1002/ecy.2947] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Accepted: 11/11/2019] [Indexed: 11/10/2022]
Affiliation(s)
- Scott Hotaling
- School of Biological Sciences Washington State University Pullman Washington 99164 USA
| | - Peter H. Wimberger
- Biology Department Slater Museum of Natural History University of Puget Sound Tacoma Washington 98416 USA
| | - Joanna L. Kelley
- School of Biological Sciences Washington State University Pullman Washington 99164 USA
| | - Heather E. Watts
- School of Biological Sciences Washington State University Pullman Washington 99164 USA
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