The Dynamics of Nutrient Enrichment and Primary Production Related to the Recent Changes in the Ecosystem of the Black Sea
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Thureborn Et Al 2013
http://www.diva-portal.org This is the published version of a paper published in PLoS ONE. Citation for the original published paper (version of record): Thureborn, P., Lundin, D., Plathan, J., Poole, A., Sjöberg, B. et al. (2013) A Metagenomics Transect into the Deepest Point of the Baltic Sea Reveals Clear Stratification of Microbial Functional Capacities. PLoS ONE, 8(9): e74983 http://dx.doi.org/10.1371/journal.pone.0074983 Access to the published version may require subscription. N.B. When citing this work, cite the original published paper. Permanent link to this version: http://urn.kb.se/resolve?urn=urn:nbn:se:sh:diva-20021 A Metagenomics Transect into the Deepest Point of the Baltic Sea Reveals Clear Stratification of Microbial Functional Capacities Petter Thureborn1,2*., Daniel Lundin1,3,4., Josefin Plathan2., Anthony M. Poole2,5, Britt-Marie Sjo¨ berg2,4, Sara Sjo¨ ling1 1 School of Natural Sciences and Environmental Studies, So¨derto¨rn University, Huddinge, Sweden, 2 Department of Molecular Biology and Functional Genomics, Stockholm University, Stockholm, Sweden, 3 Science for Life Laboratories, Royal Institute of Technology, Solna, Sweden, 4 Department of Biochemistry and Biophysics, Stockholm University, Stockholm, Sweden, 5 School of Biological Sciences, University of Canterbury, Christchurch, New Zealand Abstract The Baltic Sea is characterized by hyposaline surface waters, hypoxic and anoxic deep waters and sediments. These conditions, which in turn lead to a steep oxygen gradient, are particularly evident at Landsort Deep in the Baltic Proper. Given these substantial differences in environmental parameters at Landsort Deep, we performed a metagenomic census spanning surface to sediment to establish whether the microbial communities at this site are as stratified as the physical environment. -
Biogeochemistry of Mediterranean Wetlands: a Review About the Effects of Water-Level Fluctuations on Phosphorus Cycling and Greenhouse Gas Emissions
water Review Biogeochemistry of Mediterranean Wetlands: A Review about the Effects of Water-Level Fluctuations on Phosphorus Cycling and Greenhouse Gas Emissions Inmaculada de Vicente 1,2 1 Departamento de Ecología, Universidad de Granada, 18071 Granada, Spain; [email protected]; Tel.: +34-95-824-9768 2 Instituto del Agua, Universidad de Granada, 18071 Granada, Spain Abstract: Although Mediterranean wetlands are characterized by extreme natural water level fluctu- ations in response to irregular precipitation patterns, global climate change is expected to amplify this pattern by shortening precipitation seasons and increasing the incidence of summer droughts in this area. As a consequence, a part of the lake sediment will be exposed to air-drying in dry years when the water table becomes low. This periodic sediment exposure to dry/wet cycles will likely affect biogeochemical processes. Unexpectedly, to date, few studies are focused on assessing the effects of water level fluctuations on the biogeochemistry of these ecosystems. In this review, we investigate the potential impacts of water level fluctuations on phosphorus dynamics and on greenhouse gases emissions in Mediterranean wetlands. Major drivers of global change, and specially water level fluctuations, will lead to the degradation of water quality in Mediterranean wetlands by increasing the availability of phosphorus concentration in the water column upon rewetting of dry sediment. CO2 fluxes are likely to be enhanced during desiccation, while inundation is likely to decrease cumulative CO emissions, as well as N O emissions, although increasing CH emissions. Citation: de Vicente, I. 2 2 4 Biogeochemistry of Mediterranean However, there exists a complete gap of knowledge about the net effect of water level fluctuations Wetlands: A Review about the Effects induced by global change on greenhouse gases emission. -
8.4 the Significance of Ocean Deoxygenation for Continental Margin Mesopelagic Communities J
8.4 The significance of ocean deoxygenation for continental margin mesopelagic communities J. Anthony Koslow 8.4 The significance of ocean deoxygenation for continental margin mesopelagic communities J. Anthony Koslow Institute for Marine and Antarctic Studies, University of Tasmania, Hobart, Tasmania, Australia and Scripps Institution of Oceanography, University of California, SD, La Jolla, CA 92093 USA. Email: [email protected] Summary • Global climate models predict global warming will lead to declines in midwater oxygen concentrations, with greatest impact in regions of oxygen minimum zones (OMZ) along continental margins. Time series from these regions indicate that there have been significant changes in oxygen concentration, with evidence of both decadal variability and a secular declining trend in recent decades. The areal extent and volume of hypoxic and suboxic waters have increased substantially in recent decades with significant shoaling of hypoxic boundary layers along continental margins. • The mesopelagic communities in OMZ regions are unique, with the fauna noted for their adaptations to hypoxic and suboxic environments. However, mesopelagic faunas differ considerably, such that deoxygenation and warming could lead to the increased dominance of subtropical and tropical faunas most highly adapted to OMZ conditions. • Denitrifying bacteria within the suboxic zones of the ocean’s OMZs account for about a third of the ocean’s loss of fixed nitrogen. Denitrification in the eastern tropical Pacific has varied by about a factor of 4 over the past 50 years, about half due to variation in the volume of suboxic waters in the Pacific. Continued long- term deoxygenation could lead to decreased nutrient content and hence decreased ocean productivity and decreased ocean uptake of carbon dioxide (CO2). -
The Potential of Mangroves in the Treatment of Shrimp Aquaculture Effluent on the Eastern Coast of Thailand
The Potential of Mangroves in the Treatment of Shrimp Aquaculture Effluent on the Eastern Coast of Thailand 7 Nina Fancy B. Sc.(Horn), Queen's University, 1999 A Thesis Submitted in Partial Fulfillment of the Requirements for the Degree of MASTER OF SCIENCE in the Department of Geography O Nina Fancy, 2004 University of Victoria AII rights reserved. This thesis may not be reproduced in whole or in part, by photocopy or other means, without the permission of the author. Supervisor: Dr. Mark Flaherty ABSTRACT This thesis examines the potential of low-cost, low-maintenance mangroves in the treatment of nutrient-rich effluent originating from a shnmp fmon the coast of Thailand's Chanthaburi province. The objective of this thesis is to identify the environmental impact of shnmp aquaculture effluent and to determine if mangrove wetlands can be used as effective biofiltration areas to remove significant quantities of nitrate, ammonia and nitrite from shrimp wastewater. The study mangrove was found to remove an average of 44.5% of nitrate, 46.6% of ammonia and 59.0% of nitrite from shrimp effluent. The ratio of mangrove treatment area to shrimp fmrequired to adequately treat daily effluxes of wastewater from shrimp fmswas calculated to . be 1: 14. This ratio is significantly less spatially demanding than ratios calculated by .-: P 0 previous researchers and reveals the potential of mangroves to be used as large-scale wastewater treatment areas in shrimp-producing nations. TABLE OF CONTENTS .. ABSTRACT ..............................................................................................................11 -
Respiration in the Mesopelagic and Bathypelagic Zones of the Oceans
CHAPTER 10 Respiration in the mesopelagic and bathypelagic zones of the oceans Javier Arístegui1, Susana Agustí2, Jack J. Middelburg3, and Carlos M. Duarte2 1 Facultad de Ciencias del Mar, Universidad de las Palmas de Gran Canaria, Spain 2 IMEDEA (CSIC–UIB), Spain 3 Netherlands Institute of Ecology, The Netherlands Outline In this chapter the mechanisms of transport and remineralization of organic matter in the dark water-column and sediments of the oceans are reviewed. We compare the different approaches to estimate respiration rates, and discuss the discrepancies obtained by the different methodologies. Finally, a respiratory carbon budget is produced for the dark ocean, which includes vertical and lateral fluxes of organic matter. In spite of the uncertainties inherent in the different approaches to estimate carbon fluxes and oxygen consumption in the dark ocean, estimates vary only by a factor of 1.5. Overall, direct measurements of respiration, as well as − indirect approaches, converge to suggest a total dark ocean respiration of 1.5–1.7 Pmol C a 1. Carbon mass − balances in the dark ocean suggest that the dark ocean receives 1.5–1.6 Pmol C a 1, similar to the estimated respiration, of which >70% is in the form of sinking particles. Almost all the organic matter (∼92%) is remineralized in the water column, the burial in sediments accounts for <1%. Mesopelagic (150–1000 m) − − respiration accounts for ∼70% of dark ocean respiration, with average integrated rates of 3–4 mol C m 2 a 1, − − 6–8 times greater than in the bathypelagic zone (∼0.5 mol C m 2 a 1). -
A Dolomitization Event at the Oceanic Chemocline During the Permian-Triassic Transition Mingtao Li1, Haijun Song1*, Thomas J
https://doi.org/10.1130/G45479.1 Manuscript received 11 August 2018 Revised manuscript received 4 October 2018 Manuscript accepted 5 October 2018 © 2018 The Authors. Gold Open Access: This paper is published under the terms of the CC-BY license. Published online 23 October 2018 A dolomitization event at the oceanic chemocline during the Permian-Triassic transition Mingtao Li1, Haijun Song1*, Thomas J. Algeo1,2,3, Paul B. Wignall4, Xu Dai1, and Adam D. Woods5 1State Key Laboratory of Biogeology and Environmental Geology, School of Earth Science, China University of Geosciences, Wuhan 430074, China 2State Key Laboratory of Geological Processes and Mineral Resources, School of Earth Science, China University of Geosciences, Wuhan 430074, China 3Department of Geology, University of Cincinnati, Cincinnati, Ohio 45221-0013, USA 4School of Earth and Environment, University of Leeds, Leeds LS2 9JT, UK 5Department of Geological Sciences, California State University, Fullerton, California 92834-6850, USA ABSTRACT in dolomite in the uppermost Permian–lowermost Triassic was first noted The Permian-Triassic boundary (PTB) crisis caused major short- by Wignall and Twitchett (2002) and has been attributed to an increased term perturbations in ocean chemistry, as recorded by the precipita- weathering flux of Mg-bearing clays to the ocean (Algeo et al., 2011). tion of anachronistic carbonates. Here, we document for the first time Here, we examine the distribution of dolomite in 22 PTB sections, docu- a global dolomitization event during the Permian-Triassic transition menting a global dolomitization event and identifying additional controls based on Mg/(Mg + Ca) data from 22 sections with a global distri- on its formation during the Permian-Triassic transition. -
Linking Biodiversity Above and Below the Marine Sediment–Water Interface
Articles Linking Biodiversity Above and Below the Marine Sediment–Water Interface PAUL V. R. SNELGROVE, MELANIE C. AUSTEN, GUY BOUCHER, CARLO HEIP, PATRICIA A. HUTCHINGS, GARY M. KING, ISAO KOIKE, P. JOHN D. LAMBSHEAD, AND CRAIG R. SMITH hanges in the marine environment are evident on Ca global scale (McGowan et al. 1998), and although bio- THE ORGANISMS LIVING ON THE OCEAN diversity in the oceans is poorly described, abundances and FLOOR ARE LINKED TO THOSE LIVING IN distributions of both commercially exploited (Safina 1998) and nonexploited (Pearson and Rosenberg 1978) species have THE OCEAN ABOVE, BUT WHETHER OR changed. Not only have major changes occurred but the rate of alteration of marine ecosystems appears to be accelerating HOW THE BIODIVERSITY IN THESE TWO (e.g., Cohen and Carlton 1998). Unfortunately, the impact of these changes in biodiversity on the basic functioning of ma- REALMS IS LINKED REMAINS LARGELY rine ecosystems remains uncertain, as does the oceans’ capacity UNKNOWN to withstand multiple human disturbances (Snelgrove et al. 1997). The dynamics of many marine ecosystems, as well as of important fisheries, depend on close coupling between benthic (bottom living) and pelagic (water column) organ- The sediment–water interface (SWI) in marine ecosystems isms (Steele 1974). Our knowledge of the natural history of is one of the most clearly defined ecological boundaries on these systems remains limited, and scientific interest in map- Earth. Many organisms in the water column, such as salps ping the diversity of organisms and how they live has been and jellyfish, have flimsy and attenuated morphologies that marginalized in recent years. -
Mixing Between Oxic and Anoxic Waters of the Black Sea As Traced by Chernobyl Cesium Isotopes
Deep-Sea Research, Vol 38. Suppl 2. pp S72>-S745. 1991. 019~149191 53.00 + 0.00 Pnnted 10 Great Bntam © 1991Pergamon Press pic Mixing between oxic and anoxic waters of the Black Sea as traced by Chernobyl cesium isotopes KEN O. BUESSELER, * HUGH D. LIVINGSTON* and SUSAN A. CASSO* (Received 14 August 1989; in revised form 16 November 1990; accepted 28 November 1990) Abstract-The Chernobyl nuclear power station accident in 1986 released readily measureable quantities of fallout 134CS and 137Cs to Black Sea surface waters. This pulse-like input of tracers can be used to follow the physical mixing of the surface oxic waters, now labeled with the Chemobyl tracers, and the deeper anoxic waters, which were initially Chemobyl free. By 1988, there is clear evidence of Chernobyl Cs penetration below the oxic/anoxic interface at deep water stations in the western and eastern basins of the Black Sea. This rapid penetration of surface waters across the pycnocline cannot be explained by vertical mixing processes alone. Data from profiles at the mouth of the Bosporus suggest that significant ventilation of intermediate depths can occur as the outflowmg Black Sea waters are entrained with the inflowing Mediterranean waters, forming a sub-surface water mass which is recognized by its surface water characteristics, i.e. initially a relatively high oxygen content and Chernobyl Cs signal. The lateral propagation ofthis signal along isopycnals into the basin interior would provide a rapid and effective mechanism for ventilating intermediate depths of the Black Sea. This process could also account for the lateral injection of resuspended margin sediments into the basin interior. -
Dispersion in the Open Ocean Seasonal Pycnocline at Scales of 1–10Km and 1–6 Days
FEBRUARY 2020 S U N D E R M E Y E R E T A L . 415 Dispersion in the Open Ocean Seasonal Pycnocline at Scales of 1–10km and 1–6 days a MILES A. SUNDERMEYER AND DANIEL A. BIRCH University of Massachusetts Dartmouth, North Dartmouth, Massachusetts JAMES R. LEDWELL Woods Hole Oceanographic Institution, Woods Hole, Massachusetts b MURRAY D. LEVINE, STEPHEN D. PIERCE, AND BRANDY T. KUEBEL CERVANTES Oregon State University, Corvallis, Oregon (Manuscript received 23 January 2019, in final form 14 November 2019) ABSTRACT Results are presented from two dye release experiments conducted in the seasonal thermocline of the 2 2 Sargasso Sea, one in a region of low horizontal strain rate (;10 6 s 1), the second in a region of intermediate 2 2 horizontal strain rate (;10 5 s 1). Both experiments lasted ;6 days, covering spatial scales of 1–10 and 1–50 km for the low and intermediate strain rate regimes, respectively. Diapycnal diffusivities estimated from 26 2 21 2 21 the two experiments were kz 5 (2–5) 3 10 m s , while isopycnal diffusivities were kH 5 (0.2–3) m s , with the range in kH being less a reflection of site-to-site variability, and more due to uncertainties in the background strain rate acting on the patch combined with uncertain time dependence. The Site I (low strain) experiment exhibited minimal stretching, elongating to approximately 10 km over 6 days while maintaining a width of ;5 km, and with a notable vertical tilt in the meridional direction. By contrast, the Site II (inter- mediate strain) experiment exhibited significant stretching, elongating to more than 50 km in length and advecting more than 150 km while still maintaining a width of order 3–5 km. -
Article Is Available Gen Availability
Hydrol. Earth Syst. Sci., 23, 1763–1777, 2019 https://doi.org/10.5194/hess-23-1763-2019 © Author(s) 2019. This work is distributed under the Creative Commons Attribution 4.0 License. Oxycline oscillations induced by internal waves in deep Lake Iseo Giulia Valerio1, Marco Pilotti1,4, Maximilian Peter Lau2,3, and Michael Hupfer2 1DICATAM, Università degli Studi di Brescia, via Branze 43, 25123 Brescia, Italy 2Leibniz-Institute of Freshwater Ecology and Inland Fisheries, Müggelseedamm 310, 12587 Berlin, Germany 3Université du Quebec à Montréal (UQAM), Department of Biological Sciences, Montréal, QC H2X 3Y7, Canada 4Civil & Environmental Engineering Department, Tufts University, Medford, MA 02155, USA Correspondence: Giulia Valerio ([email protected]) Received: 22 October 2018 – Discussion started: 23 October 2018 Revised: 20 February 2019 – Accepted: 12 March 2019 – Published: 2 April 2019 Abstract. Lake Iseo is undergoing a dramatic deoxygena- 1 Introduction tion of the hypolimnion, representing an emblematic exam- ple among the deep lakes of the pre-alpine area that are, to a different extent, undergoing reduced deep-water mixing. In Physical processes occurring at the sediment–water inter- the anoxic deep waters, the release and accumulation of re- face of lakes crucially control the fluxes of chemical com- duced substances and phosphorus from the sediments are a pounds across this boundary (Imboden and Wuest, 1995) major concern. Because the hydrodynamics of this lake was with severe implications for water quality. In stratified shown to be dominated by internal waves, in this study we in- lakes, the boundary-layer turbulence is primarily caused by vestigated, for the first time, the role of these oscillatory mo- wind-driven internal wave motions (Imberger, 1998). -
Scientific Assessment of Hypoxia in U.S. Coastal Waters
Scientific Assessment of Hypoxia in U.S. Coastal Waters 0 Dissolved oxygen (mg/L) 6 0 Depth (m) 80 32 Salinity 34 Interagency Working Group on Harmful Algal Blooms, Hypoxia, and Human Health September 2010 This document should be cited as follows: Committee on Environment and Natural Resources. 2010. Scientific Assessment of Hypoxia in U.S. Coastal Waters. Interagency Working Group on Harmful Algal Blooms, Hypoxia, and Human Health of the Joint Subcommittee on Ocean Science and Technology. Washington, DC. Acknowledgements: Many scientists and managers from Federal and state agencies, universities, and research institutions contributed to the knowledge base upon which this assessment depends. Many thanks to all who contributed to this report, and special thanks to John Wickham and Lynn Dancy of NOAA National Centers for Coastal Ocean Science for their editing work. Cover and Sidebar Photos: Background Cover and Sidebar: MODIS satellite image courtesy of the Ocean Biology Processing Group, NASA Goddard Space Flight Center. Cover inset photos from top: 1) CTD rosette, EPA Gulf Ecology Division; 2) CTD profile taken off the Washington coast, project funded by Bonneville Power Administration and NOAA Fisheries; Joseph Fisher, OSU, was chief scientist on the FV Frosti; data were processed and provided by Cheryl Morgan, OSU); 3) Dead fish, Christopher Deacutis, Rhode Island Department of Environmental Management; 4) Shrimp boat, EPA. Council on Environmental Quality Office of Science and Technology Policy Executive Office of the President Dear Partners and Friends in our Ocean and Coastal Community, We are pleased to transmit to you this report, Scientific Assessment ofHypoxia in u.s. -
Diversité Phylogénétique Et Fonctionnelle Des Eumycètes Dans Les Écosystèmes Pélagiques Marlène Jobard-Portas
Diversité phylogénétique et fonctionnelle des Eumycètes dans les écosystèmes pélagiques Marlène Jobard-Portas To cite this version: Marlène Jobard-Portas. Diversité phylogénétique et fonctionnelle des Eumycètes dans les écosystèmes pélagiques. Sciences agricoles. Université Blaise Pascal - Clermont-Ferrand II, 2010. Français. NNT : 2010CLF22090. tel-00769938 HAL Id: tel-00769938 https://tel.archives-ouvertes.fr/tel-00769938 Submitted on 4 Jan 2013 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. UNIVERSITE BLAISE PASCAL Année 2010 N°D.U. 2090 ECOLE DOCTORALE DES SCIENCES DE LA VIE, SANTE, AGRONOMIE, ENVIRONNEMENT N° d’ordre 535 Thèse Présentée à l’Université Blaise Pascal pour l’obtention du grade de DOCTEUR D’UNIVERSITE (Spécialité : Ecologie Microbienne) Soutenue le 14 Décembre 2010 Marlène JOBARD Diversité phylogénétique et fonctionnelle des Eumycètes dans les écosystèmes pélagiques Président : Pr Gilles Bourdier, Université Blaise Pascal, Clermont-Fd, France Invité Institutionnel : Dr Henry-Michel Cauchie, CRP, Belvaux, Luxembourg Directeur de