What You See Is Not What You Catch: a Comparison of Concurrently
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Effects of Eutrophication on Stream Ecosystems
EFFECTS OF EUTROPHICATION ON STREAM ECOSYSTEMS Lei Zheng, PhD and Michael J. Paul, PhD Tetra Tech, Inc. Abstract This paper describes the effects of nutrient enrichment on the structure and function of stream ecosystems. It starts with the currently well documented direct effects of nutrient enrichment on algal biomass and the resulting impacts on stream chemistry. The paper continues with an explanation of the less well documented indirect ecological effects of nutrient enrichment on stream structure and function, including effects of excess growth on physical habitat, and alterations to aquatic life community structure from the microbial assemblage to fish and mammals. The paper also dicusses effects on the ecosystem level including changes to productivity, respiration, decomposition, carbon and other geochemical cycles. The paper ends by discussing the significance of these direct and indirect effects of nutrient enrichment on designated uses - especially recreational, aquatic life, and drinking water. 2 1. Introduction 1.1 Stream processes Streams are all flowing natural waters, regardless of size. To understand the processes that influence the pattern and character of streams and reduce natural variation of different streams, several stream classification systems (including ecoregional, fluvial geomorphological, and stream order classification) have been adopted by state and national programs. Ecoregional classification is based on geology, soils, geomorphology, dominant land uses, and natural vegetation (Omernik 1987). Fluvial geomorphological classification explains stream and slope processes through the application of physical principles. Rosgen (1994) classified stream channels in the United States into seven major stream types based on morphological characteristics, including entrenchment, gradient, width/depth ratio, and sinuosity in various land forms. -
Microscale Ecology Regulates Particulate Organic Matter Turnover in Model Marine Microbial Communities
ARTICLE DOI: 10.1038/s41467-018-05159-8 OPEN Microscale ecology regulates particulate organic matter turnover in model marine microbial communities Tim N. Enke1,2, Gabriel E. Leventhal 1, Matthew Metzger1, José T. Saavedra1 & Otto X. Cordero1 The degradation of particulate organic matter in the ocean is a central process in the global carbon cycle, the mode and tempo of which is determined by the bacterial communities that 1234567890():,; assemble on particle surfaces. Here, we find that the capacity of communities to degrade particles is highly dependent on community composition using a collection of marine bacteria cultured from different stages of succession on chitin microparticles. Different particle degrading taxa display characteristic particle half-lives that differ by ~170 h, comparable to the residence time of particles in the ocean’s mixed layer. Particle half-lives are in general longer in multispecies communities, where the growth of obligate cross-feeders hinders the ability of degraders to colonize and consume particles in a dose dependent manner. Our results suggest that the microscale community ecology of bacteria on particle surfaces can impact the rates of carbon turnover in the ocean. 1 Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA. 2 Department of Environmental Systems Science, ETH Zurich, Zürich 8092, Switzerland. Correspondence and requests for materials should be addressed to O.X.C. (email: [email protected]) NATURE COMMUNICATIONS | (2018) 9:2743 | DOI: 10.1038/s41467-018-05159-8 | www.nature.com/naturecommunications 1 ARTICLE NATURE COMMUNICATIONS | DOI: 10.1038/s41467-018-05159-8 earning how the composition of ecological communities the North Pacific gyre20. -
Plankton Community Composition, Organic Carbon and Thorium-234 Particle Size Distributions, and Particle Export in the Sargasso Sea
Journal of Marine Research, 67, 845–868, 2009 Plankton community composition, organic carbon and thorium-234 particle size distributions, and particle export in the Sargasso Sea by H. S. Brew1, S. B. Moran1,2, M. W. Lomas3 and A. B. Burd4 ABSTRACT Measurements of plankton community composition (eight planktonic groups), particle size- fractionated (10, 20, 53, 70, and 100-m Nitex screens) distributions of organic carbon (OC) and 234Th, and particle export of OC and 234Th are reported over a seasonal cycle (2006–2007) from the Bermuda Atlantic Time-Series (BATS) site. Results indicate a convergence of the particle size distributions of OC and 234Th during the winter-spring bloom period (January–March, 2007). The observed convergence of these particle size distributions is directly correlated to the depth-integrated abundance of autotrophic pico-eukaryotes (r ϭ 0.97, P Ͻ 0.05) and, to a lesser extent, Synechococcus (r ϭ 0.85, P ϭ 0.14). In addition, there are positive correlations between the sediment trap flux of OC and 234Th at 150 m and the depth-integrated abundance of pico-eukaryotes (r ϭ 0.94, P ϭ 0.06 for OC, and r ϭ 0.98, P Ͻ 0.05 for 234Th) and Synechococcus (r ϭ 0.95, P ϭ 0.05 for OC, and r ϭ 0.94, P ϭ 0.06 for 234Th). An implication of these observations and recent modeling studies (Richardson and Jackson, 2007) is that, although small in size, pico-plankton may influence large particle export from the surface waters of the subtropical Atlantic. -
Beyond Eutrophication: Vancouver Lake, WA, USA As a Model System for Assessing Multiple, Interacting Biotic and Abiotic Drivers of Harmful Cyanobacterial Blooms
water Article Beyond Eutrophication: Vancouver Lake, WA, USA as a Model System for Assessing Multiple, Interacting Biotic and Abiotic Drivers of Harmful Cyanobacterial Blooms Gretchen Rollwagen-Bollens 1,2,*, Tammy Lee 1, Vanessa Rose 1 and Stephen M. Bollens 1,2 1 School of the Environment, Washington State University, Vancouver, WA, 98686, USA; [email protected] (T.L.); [email protected] (V.R.); [email protected] (S.M.B.) 2 School of Biological Sciences, Washington State University, Vancouver, WA 98686, USA * Correspondence: [email protected]; Tel.: +1-360-546-9115 Received: 16 April 2018; Accepted: 8 June 2018; Published: 10 June 2018 Abstract: Eutrophication of lakes and reservoirs has contributed to an increase in the magnitude and frequency of harmful cyanobacterial blooms; however, the interactive effects of nutrient availability (eutrophication) and other abiotic and biotic drivers have rarely been comprehensively studied in the field. We undertook an eight-year (2005–2013) research program that assessed the interaction of multiple factors driving cyanobacterial blooms in Vancouver Lake, a large, shallow eutrophic lake in Washington, USA. Our program consisted of nearly continuous monthly or weekly monitoring of water quality and plankton community composition over eight years, as well as multiple zooplankton grazing experiments over three years. We found a relatively consistent seasonal succession of phytoplankton and zooplankton assemblages, and a pattern of interacting factors influencing cyanobacterial bloom dynamics. Typically, a combined effect of decreased dissolved inorganic nitrogen (N), a sudden increase of dissolved inorganic phosphorus (P), and a cascading effect of zooplankton grazing created a ‘perfect storm’ of conditions that promoted the rapid proliferation of cyanobacteria over the two to three weeks before a bloom. -
A View of Physical Mechanisms for Transporting Harmful Algal Blooms to T Massachusetts Bay ⁎ Yu Zhanga, , Changsheng Chenb, Pengfei Xueb,1, Robert C
Marine Pollution Bulletin 154 (2020) 111048 Contents lists available at ScienceDirect Marine Pollution Bulletin journal homepage: www.elsevier.com/locate/marpolbul A view of physical mechanisms for transporting harmful algal blooms to T Massachusetts Bay ⁎ Yu Zhanga, , Changsheng Chenb, Pengfei Xueb,1, Robert C. Beardsleyc, Peter J.S. Franksd a College of Marine Sciences, Shanghai Ocean University, Shanghai 201306, PR China b School for Marine Science and Technology, University of Massachusetts-Dartmouth, New Bedford, MA 02744, USA c Department of Physical Oceanography, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA d Integrative Oceanography Division, Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA 92093, USA ARTICLE INFO ABSTRACT Keywords: Physical dynamics of Harmful Algal Blooms in Massachusetts Bay in May 2005 and 2008 were examined by the Harmful algal bloom simulated results. Reverse particle-tracking experiments suggest that the toxic phytoplankton mainly originated Massachusetts Bay from the Bay of Fundy in 2005 and the western Maine coastal region and its local rivers in 2008. Mechanism Ocean modeling studies suggest that the phytoplankton were advected by the Gulf of Maine Coastal Current (GMCC). In 2005, Lagrangian flow Nor'easters increased the cross-shelf surface elevation gradient over the northwestern shelf. This intensified the Eastern and Western MCC to form a strong along-shelf current from the Bay of Fundy to Massachusetts Bay. In 2008, both Eastern and Western MCC were established with a partial separation around Penobscot Bay before the outbreak of the bloom. The northeastward winds were too weak to cancel or reverse the cross-shelf sea surface gradient, so that the Western MCC carried the algae along the slope into Massachusetts Bay. -
Open Ocean Dead-Zones in the Tropical J I Northeast Atlantic
Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Biogeosciences Discuss., 11, 17391–17411, 2014 www.biogeosciences-discuss.net/11/17391/2014/ doi:10.5194/bgd-11-17391-2014 BGD © Author(s) 2014. CC Attribution 3.0 License. 11, 17391–17411, 2014 This discussion paper is/has been under review for the journal Biogeosciences (BG). Open ocean Please refer to the corresponding final paper in BG if available. dead-zones Open ocean dead-zone in the tropical J. Karstensen et al. North Atlantic Ocean Title Page 1 1 1 1 1 2 J. Karstensen , B. Fiedler , F. Schütte , P. Brandt , A. Körtzinger , G. Fischer , Abstract Introduction R. Zantopp1, J. Hahn1, M. Visbeck1, and D. Wallace3 Conclusions References 1GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel, Germany Tables Figures 2Faculty of Geosciences and MARUM, University of Bremen, Bremen, Germany 3Halifax Marine Research Institute (HMRI), Halifax, Canada J I Received: 3 November 2014 – Accepted: 13 November 2014 – Published: 12 December 2014 J I Correspondence to: J. Karstensen ([email protected]) Back Close Published by Copernicus Publications on behalf of the European Geosciences Union. Full Screen / Esc Printer-friendly Version Interactive Discussion 17391 Discussion Paper | Discussion Paper | Discussion Paper | Discussion Paper | Abstract BGD The intermittent appearances of low oxygen environments are a particular thread for marine ecosystems. Here we present first observations of unexpected low (< 11, 17391–17411, 2014 2 µmolkg−1) oxygen environments in the open waters of the eastern tropical North −1 5 Atlantic, a region where typically oxygen concentration does not fall below 40 µmolkg . Open ocean The low oxygen zones are created just below the mixed-layer, in the euphotic zone of dead-zones high productive cyclonic and anticyclonic-modewater eddies. -
NIST Recommended Practice Guide : Particle Size Characterization
NATL INST. OF, STAND & TECH r NIST guide PUBLICATIONS AlllOb 222311 ^HHHIHHHBHHHHHHHHBHI ° Particle Size ^ Characterization Ajit Jillavenkatesa Stanley J. Dapkunas Lin-Sien H. Lum Nisr National Institute of Specidl Standards and Technology Publication Technology Administration U.S. Department of Commerce 960 - 1 NIST Recommended Practice Gu Special Publication 960-1 Particle Size Characterization Ajit Jillavenkatesa Stanley J. Dapkunas Lin-Sien H. Lum Materials Science and Engineering Laboratory January 2001 U.S. Department of Commerce Donald L. Evans, Secretary Technology Administration Karen H. Brown, Acting Under Secretary of Commerce for Technology National Institute of Standards and Technology Karen H. Brown, Acting Director Certain commercial entities, equipment, or materials may be identified in this document in order to describe an experimental procedure or concept adequately. Such identification is not intended to imply recommendation or endorsement by the National Institute of Standards and Technology, nor is it intended to imply that the entities, materials, or equipment are necessarily the best available for the purpose. National Institute of Standards and Technology Special Publication 960-1 Natl. Inst. Stand. Technol. Spec. Publ. 960-1 164 pages (January 2001) CODEN: NSPUE2 U.S. GOVERNMENT PRINTING OFFICE WASHINGTON: 2001 For sale by the Superintendent of Documents U.S. Government Printing Office Internet: bookstore.gpo.gov Phone: (202)512-1800 Fax: (202)512-2250 Mail: Stop SSOP, Washington, DC 20402-0001 Preface PREFACE Determination of particle size distribution of powders is a critical step in almost all ceramic processing techniques. The consequences of improper size analyses are reflected in poor product quality, high rejection rates and economic losses. -
A Primer on Limnology, Second Edition
BIOLOGICAL PHYSICAL lake zones formation food webs variability primary producers light chlorophyll density stratification algal succession watersheds consumers and decomposers CHEMICAL general lake chemistry trophic status eutrophication dissolved oxygen nutrients ecoregions biological differences The following overview is taken from LAKE ECOLOGY OVERVIEW (Chapter 1, Horne, A.J. and C.R. Goldman. 1994. Limnology. 2nd edition. McGraw-Hill Co., New York, New York, USA.) Limnology is the study of fresh or saline waters contained within continental boundaries. Limnology and the closely related science of oceanography together cover all aquatic ecosystems. Although many limnologists are freshwater ecologists, physical, chemical, and engineering limnologists all participate in this branch of science. Limnology covers lakes, ponds, reservoirs, streams, rivers, wetlands, and estuaries, while oceanography covers the open sea. Limnology evolved into a distinct science only in the past two centuries, when improvements in microscopes, the invention of the silk plankton net, and improvements in the thermometer combined to show that lakes are complex ecological systems with distinct structures. Today, limnology plays a major role in water use and distribution as well as in wildlife habitat protection. Limnologists work on lake and reservoir management, water pollution control, and stream and river protection, artificial wetland construction, and fish and wildlife enhancement. An important goal of education in limnology is to increase the number of people who, although not full-time limnologists, can understand and apply its general concepts to a broad range of related disciplines. A primary goal of Water on the Web is to use these beautiful aquatic ecosystems to assist in the teaching of core physical, chemical, biological, and mathematical principles, as well as modern computer technology, while also improving our students' general understanding of water - the most fundamental substance necessary for sustaining life on our planet. -
Longitudinal Changes in the Abundance of Filter Feeders and Zooplankton in Lake-Outlet Streams in Northern Sweden
Ann. Limnol. 37 (3) 2001 : 199-209 Longitudinal changes in the abundance of filter feeders and zooplankton in lake-outlet streams in northern Sweden Â.I. Eriksson1 Keywords : filter feeders, zooplankton, longitudinal distribution, lake-outlet streams. The Sheldon & Oswood (1977) model, that predicts a linear relationship between log filter-feeder density and log distance from a lake and assumes proportionality between filter-feeder density and seston concentration, was tested on data from four lake-outlet streams. In addition, longitudinal changes in species composition and body size in zooplankton were investigated. Most filter feeders deviated from the model and a quadratic, rather than linear, decrease in density was a common pattern. Total filter feeders and blackfly larvae showed a hump-shaped distribution pattern. Lower current velocity at sites close to lakes is suggested as an explanation. No general proportional relationship between net-spinning caddis larvae and zooplankton was found and several reasons for this result are discussed. Zooplankton biomass and mean zooplankton body length decreased with distance from lakes. The abundance of cyclopoid adults, copepodites, and nauplii declined at a higher rate than Bosmina spp.l This result indicates that factors such as selective prédation by filter-feeders and/or taxon-specific sedimentation rates, are acting to reduce zooplankton abundance in these lake-outlet streams. Variations longitudinales dans l'abondance des organismes fîltreurs et du zooplancton dans les déversoirs de lac du nord de la Suède Mots-clés : organismes fîltreurs, zooplancton, distribution longitudinale, réservoirs de lac. Le modèle de Sheldon & Oswood (1977) qui prédit une relation linéaire entre le log de la densité des organismes et le log de la distance du lac et qui se manifeste par une proportionnalité entre la densité des organismes filtreurs et la concentration du ses ton, a été contrôlé sur des données recueillies sur quatre cours d'eau déversoirs de lac. -
Particle Aggregation During a Diatom Bloom. 11. Biological Aspects
MARINE ECOLOGY PROGRESS SERIES Published January 24 Mar. Ecol. Prog. Ser. Particle aggregation during a diatom bloom. 11. Biological aspects Ulf Riebesell Alfred Wegener Institute for Polar and Marine Research, Colurnbusstr., D-2850 Bremerhaven. Germany ABSTRACT: For a 6 wk period covering the time before, during, and after the phytoplankton spring bloom, macroscopic aggregates (20.5 mm diameter) were repeatedly collected and water column properties simultaneously measured at a fixed station in the Southern North Sea. Distinct changes in aggregate structure and composition were observed during the study. Predominantly detrital aggregates dur~ngthe early phase of the study were followed by diatom-dominated algal flocs around the peak of the bloom. Mucus-rich aggregates containing both algal and detrital components and with large numbers of attached bacteria dominated the post-bloom interval. The phytoplankton succession within the aggregates closely reflected the succession in the water column with a time delay of a few days. Algal flocculation did not occur as a simultaneous aggregation of the entire phytoplankton community, but as a successional aggregat~onof selected diatom species. Although the concentrations of ~norganicnutrients diminished considerably during the development of the phytoplankton bloom, the termination of the bloom appeared to be mostly controlled by physical coagulation processes. The importance of biologically-controlled factors for physical coagulation is discussed. INTRODUCTION stickiness, proposed that physical processes alone could determine the time and extent of algal aggregation. Mass flocculation during diatom blooms as predicted Based on a physical coagulation model, Jackson pre- by Smetacek (1985) has since been documented both in dicted that the rate of aggregation strongly depends on the field (Kranck & Milligan 1988, Alldredge & Got- algal concentration. -
Eutrophication and Health Printed Infrance- PRINTED ONWHITECHLORINE-FREE PAPER Reproduction Isauthorised Providedthesourceisacknowledged
World Health Organization EUROPEAN COMMISSION Regional Office for Europe Eutrophication and health 40 water Eutrophication and health Algal blooms, “red tides”, “green tides”, fish kills, inedible shellfish, blue algae and public health threats. What is the common link ? The answer is, EUTROPHICATION: a complex process which occurs both in fresh and marine waters, where excessive development of certain types of algae disturbs the aquatic ecosystems and becomes a threat for animal and human health. The primary cause of eutrophication is an excessive concentration of plant nutrients originating from agriculture or sewage treatment. The purpose of this booklet is to describe in a simple way the causes of eutrophication, the environmental effects, the associated nuisances and health risk as well as the preventive and mitigating measures. It is hoped that the booklet, which represents a collaborative effort between the European Commission and the WHO, will contribute to a better understanding of the problem of eutrophication and a more effective control of nutrient enrichment in our lakes, rivers ans seas. preface Dr Günter KLEIN Prudencio PERERA Head of office Director WHO European Centre for Environment Environment Quality and Natural Resources and Health Bonn Office European Commission A great deal of additional information on the European Union is available on the Internet. It can be accessed through the Europa server (http://europa.eu.int). Cataloguing data can be found at the end of this publication. Luxembourg: Office for Official Publications of the European Communities, 2002 ISBN 92-894-4413-4 © European Communities, 2002 Reproduction is authorised provided the source is acknowledged. Printed in France - PRINTED ON WHITE CHLORINE-FREE PAPER Local authorities - this publication is meant for you WHO’s Regional Office for Europe is regularly approached to provide technical or practical advice on a large number of questions related to health and the environment. -
Environmental Studies Program: Ongoing Study
Environmental Studies Program: Ongoing Study Title Assessing the Impact of Oil Spills Using Three-Dimensional Oil Spill Modeling (NSL #PC-16-03) Administered by Pacific OCS Region BOEM Contact(s) Susan Zaleski ([email protected]) Procurement Type(s) Inter-agency Agreement Conducting Organizations(s) National Oceanic and Atmospheric Administration, Office of Response and Restoration Total BOEM Cost $478,000 Performance Period FY 2016–2022 Final Report Due July 21, 2022 Date Revised January 22, 2021 PICOC Summary Problem BOEM has limited ability to assess the impact of a potential oil spill to subsurface biota. Intervention Pilot test a 3D oil spill model and expand BOEM Pacific Region’s oil spill modeling capability. Comparison Compare new model outputs to previous analyses. Outcome Updated oil spill modeling capability Context Southern California Planning Area BOEM Information Need(s): Currently the offshore oil and gas risk analysis conducted by the BOEM Pacific Region is based on a two-dimensional oil spill model, which only predicts surface transport of oil spills. However, oil spills can have significant impact to the subsurface. The impact of oil spills to the subsurface can only be predicted using three-dimensional oil spill modeling. The aim of this study is to implement a three-dimensional oil spill model in southern California and to assess the impact of oil spills to subsurface biota. This study will expand BOEM Pacific Region’s capability to conduct oil spill risk analysis in southern California. Background: BOEM Pacific region currently uses the General NOAA Oil Modeling Environment (GNOME), which is a two-dimensional oil spill model, for oil and gas risk analysis.