Articles Recycled Trite Maximum Generally Does Not Occur in the Region
Total Page:16
File Type:pdf, Size:1020Kb
Load more
Recommended publications
-
A Model for the Oceanic Mass Balance of Rhenium and Implications for the Extent of Proterozoic Ocean Anoxia
UC Riverside UC Riverside Previously Published Works Title A model for the oceanic mass balance of rhenium and implications for the extent of Proterozoic ocean anoxia Permalink https://escholarship.org/uc/item/1gh1h920 Journal GEOCHIMICA ET COSMOCHIMICA ACTA, 227 ISSN 0016-7037 Authors Sheen, Alex I Kendall, Brian Reinhard, Christopher T et al. Publication Date 2018-04-15 DOI 10.1016/j.gca.2018.01.036 Peer reviewed eScholarship.org Powered by the California Digital Library University of California Available online at www.sciencedirect.com ScienceDirect Geochimica et Cosmochimica Acta 227 (2018) 75–95 www.elsevier.com/locate/gca A model for the oceanic mass balance of rhenium and implications for the extent of Proterozoic ocean anoxia Alex I. Sheen a,b,⇑, Brian Kendall a, Christopher T. Reinhard c, Robert A. Creaser b, Timothy W. Lyons d, Andrey Bekker d, Simon W. Poulton e, Ariel D. Anbar f,g a Department of Earth and Environmental Sciences, University of Waterloo, 200 University Avenue West, Waterloo, Ontario N2L 3G1, Canada b Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, Alberta T6G 2E3, Canada c School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA 30332, USA d Department of Earth Sciences, University of California, Riverside, CA 92521, USA e School of Earth and Environment, University of Leeds, Leeds LS2 9JT, UK f School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85287, USA g School of Molecular Sciences, Arizona State University, Tempe, AZ 85287, USA Received 13 July 2017; accepted in revised form 30 January 2018; available online 8 February 2018 Abstract Emerging geochemical evidence suggests that the atmosphere-ocean system underwent a significant decrease in O2 content following the Great Oxidation Event (GOE), leading to a mid-Proterozoic ocean (ca. -
Cascading of Habitat Degradation: Oyster Reefs Invaded by Refugee Fishes Escaping Stress
Ecological Applications, 11(3), 2001, pp. 764±782 q 2001 by the Ecological Society of America CASCADING OF HABITAT DEGRADATION: OYSTER REEFS INVADED BY REFUGEE FISHES ESCAPING STRESS HUNTER S. LENIHAN,1 CHARLES H. PETERSON,2 JAMES E. BYERS,3 JONATHAN H. GRABOWSKI,2 GORDON W. T HAYER, AND DAVID R. COLBY NOAA-National Ocean Service, Center for Coastal Fisheries and Habitat Research, 101 Pivers Island Road, Beaufort, North Carolina 28516 USA Abstract. Mobile consumers have potential to cause a cascading of habitat degradation beyond the region that is directly stressed, by concentrating in refuges where they intensify biological interactions and can deplete prey resources. We tested this hypothesis on struc- turally complex, species-rich biogenic reefs created by the eastern oyster, Crassostrea virginica, in the Neuse River estuary, North Carolina, USA. We (1) sampled ®shes and invertebrates on natural and restored reefs and on sand bottom to compare ®sh utilization of these different habitats and to characterize the trophic relations among large reef-as- sociated ®shes and benthic invertebrates, and (2) tested whether bottom-water hypoxia and ®shery-caused degradation of reef habitat combine to induce mass emigration of ®sh that then modify community composition in refuges across an estuarine seascape. Experimen- tally restored oyster reefs of two heights (1 m tall ``degraded'' or 2 m tall ``natural'' reefs) were constructed at 3 and 6 m depths. We sampled hydrographic conditions within the estuary over the summer to monitor onset and duration of bottom-water hypoxia/anoxia, a disturbance resulting from density strati®cation and anthropogenic eutrophication. Reduc- tion of reef height caused by oyster dredging exposed the reefs located in deep water to hypoxia/anoxia for .2 wk, killing reef-associated invertebrate prey and forcing mobile ®shes into refuge habitats. -
Son of Perdition Free Download
SON OF PERDITION FREE DOWNLOAD Wendy Alec | 490 pages | 01 Apr 2010 | Warboys Publishing (Ireland) Limited | 9780956333001 | English | Dublin, Ireland Who Is the Son of Perdition? The unembodied spirits who supported Lucifer in the war in heaven and were cast out Moses and mortals who commit Son of Perdition unpardonable sin against the Holy Ghost will inherit the same condition as Lucifer and Cain, and thus are called "sons of Son of Perdition. Contrasting beliefs. Recently Popular Media x. Verse Only. BLB Searches. So who is he? The bible describes the behavior of one who worships Jesus Christ. The purposes of the Son of Perdition oppose those of Jesus. A verification email has been sent to the address you provided. Blue Letter Bible study tools make reading, Son of Perdition and studying the Bible easy and rewarding. Extinction event Holocene extinction Human extinction List of extinction events Genetic erosion Son of Perdition pollution. Christianity portal. Re-type Password. Even a believer who maintains the faith can become discouraged and lose the peace of the Holy Spirit when he is cut off from the body of Christ. Biblical texts. By proceeding, you consent to our cookie usage. Back Psalms 1. The Son of Perdition is the progeny of abuse and desolation. Sort Canonically. The Millennium. No Number. Advanced Options Exact Match. However, scripture declares that "the soul can never die" Son of Perdition and that in the Resurrection the spirit and the body are united "never to be divided" Alma ; cf. Individual instructors or editors may still require Son of Perdition use of URLs. -
Substantial Vegetation Response to Early Jurassic Global Warming with Impacts on Oceanic Anoxia
ARTICLES https://doi.org/10.1038/s41561-019-0349-z Substantial vegetation response to Early Jurassic global warming with impacts on oceanic anoxia Sam M. Slater 1*, Richard J. Twitchett2, Silvia Danise3 and Vivi Vajda 1 Rapid global warming and oceanic oxygen deficiency during the Early Jurassic Toarcian Oceanic Anoxic Event at around 183 Ma is associated with a major turnover of marine biota linked to volcanic activity. The impact of the event on land-based eco- systems and the processes that led to oceanic anoxia remain poorly understood. Here we present analyses of spore–pollen assemblages from Pliensbachian–Toarcian rock samples that record marked changes on land during the Toarcian Oceanic Anoxic Event. Vegetation shifted from a high-diversity mixture of conifers, seed ferns, wet-adapted ferns and lycophytes to a low-diversity assemblage dominated by cheirolepid conifers, cycads and Cerebropollenites-producers, which were able to sur- vive in warm, drought-like conditions. Despite the rapid recovery of floras after Toarcian global warming, the overall community composition remained notably different after the event. In shelf seas, eutrophication continued throughout the Toarcian event. This is reflected in the overwhelming dominance of algae, which contributed to reduced oxygen conditions and to a marked decline in dinoflagellates. The substantial initial vegetation response across the Pliensbachian/Toarcian boundary compared with the relatively minor marine response highlights that the impacts of the early stages of volcanogenic -
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 -
18 Exchanges of Carbon in the Coastal Seas Chen-Tung Arthur Chen
Scope 62-II.qxd 11/12/03 4:20 PM Page 341 18 Exchanges of Carbon in the Coastal Seas Chen-Tung Arthur Chen In the natural carbon cycle, the time period for atmosphere-biosphere exchange ranges from only a few months to a few decades. The exchange of CO2 between the atmos- phere and the hydrosphere, by contrast, takes several hundred years if the interior of the oceans is taken into consideration. The exchange is much more rapid, however, on a time scale of a few years or even less, for only the terrestrial hydrosphere and the sur- face mixed layer of the oceans. The time for the atmosphere-lithosphere exchange is very long, requiring many thousands of years or more. The shallow sediments on the conti- nental shelves interact relatively readily with the atmosphere. Some terrestrial material even crosses the shelves, which have a mean width of 70 kilometers (km) and a total area of 26 × 106 km2, and efficiently reaches the slopes, which start at an average depth of 130 meters (m) (Gattuso et al. 1998). Dissolved organic matter may also be swiftly car- ried to the interior of the oceans through intermediate bodies of water in certain areas, including the Arctic, Okhotsk, Mediterranean, and Red Seas (Walsh 1995; Chen et al. 2003). The specific rates of productivity, biogeochemical cycling, and sequestration of CO2 are higher in the continental margins than in the open oceans. The end result is that it may take only years, as opposed to hundreds of years, for the atmosphere, lith- osphere, biosphere, and hydrosphere to interact in the continental margins. -
Carbon Cycling in the North American Coastal Ocean: a Synthesis
Biogeosciences, 16, 1281–1304, 2019 https://doi.org/10.5194/bg-16-1281-2019 © Author(s) 2019. This work is distributed under the Creative Commons Attribution 4.0 License. Carbon cycling in the North American coastal ocean: a synthesis Katja Fennel1, Simone Alin2, Leticia Barbero3, Wiley Evans4, Timothée Bourgeois1, Sarah Cooley5, John Dunne6, Richard A. Feely2, Jose Martin Hernandez-Ayon7, Xinping Hu8, Steven Lohrenz9, Frank Muller-Karger10, Raymond Najjar11, Lisa Robbins10, Elizabeth Shadwick12, Samantha Siedlecki13, Nadja Steiner14, Adrienne Sutton2, Daniela Turk15, Penny Vlahos13, and Zhaohui Aleck Wang16 1Department of Oceanography, Dalhousie University, 1355 Oxford Street, Halifax B3H 4R2, Nova Scotia, Canada 2NOAA Pacific Marine Environmental Laboratory, Seattle, WA 98115, USA 3NOAA Atlantic Oceanographic and Meteorological Laboratory, Miami, FL 33149, USA 4Hakai Institute, Campbell River, BC, V9W 0B7, Canada 5Ocean Conservancy, USA 6NOAA Geophysical Fluid Dynamics Laboratory, Princeton, NJ 08540, USA 7Department of Marine Science, Autonomous University of Baja California, Ensenada, Baja California, CP 228600, Mexico 8Department of Physical and Environmental Sciences, Texas A&M University, Corpus Christi, TX 78412, USA 9School for Marine Science and Technology, University of Massachusetts, Dartmouth, MA 02747, USA 10Department of Marine Science, University of South Florida, Tampa, FL 33620, USA 11Department of Meteorology and Atmospheric Sciences, University Park, Pennsylvania 16802, USA 12The Department is Oceans & Atmosphere. The Institution is CSIRO, Hobart, TAS 7000, Australia 13Marine Sciences, University of Connecticut, Groton, CT 06340, USA 14Department of Fisheries and Oceans Canada, Sidney, BC V8L 4B2, Canada 15Lamont-Doherty Earth Observatory, Palisades, NY 10964, USA 16Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA Correspondence: Katja Fennel ([email protected]) Received: 19 September 2018 – Discussion started: 20 September 2018 Revised: 28 February 2019 – Accepted: 8 March 2019 – Published: 27 March 2019 Abstract. -
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. -
Effects of Natural and Human-Induced Hypoxia on Coastal Benthos
Biogeosciences, 6, 2063–2098, 2009 www.biogeosciences.net/6/2063/2009/ Biogeosciences © Author(s) 2009. This work is distributed under the Creative Commons Attribution 3.0 License. Effects of natural and human-induced hypoxia on coastal benthos L. A. Levin1, W. Ekau2, A. J. Gooday3, F. Jorissen4, J. J. Middelburg5, S. W. A. Naqvi6, C. Neira1, N. N. Rabalais7, and J. Zhang8 1Integrative Oceanography Division, Scripps Institution of Oceanography, 9500 Gilman Drive, La Jolla, CA 92093-0218, USA 2Fisheries Biology, Leibniz Zentrum fur¨ Marine Tropenokologie,¨ Leibniz Center for Tropical Marine Ecology, Fahrenheitstr. 6, 28359 Bremen, Germany 3National Oceanography Centre, Southampton, European Way, Southampton SO14 3ZH, UK 4Laboratory of Recent and Fossil Bio-Indicators (BIAF), Angers University, 2 Boulevard Lavoisier, 49045 Angers Cedex 01, France 5Faculty of Geosciences, Utrecht University, P.O. Box 80021, 3508 TA Utrecht, The Netherlands 6National Institution of Oceanography, Dona Paula, Goa 403004, India 7Louisiana Universities Marine Consortium, Chauvin, Louisiana 70344, USA 8State Key Laboratory of Estuarine and Coastal Research, East China Normal University, 3663 Zhongshan Road North, Shanghai 200062, China Received: 17 January 2009 – Published in Biogeosciences Discuss.: 3 April 2009 Revised: 21 August 2009 – Accepted: 21 August 2009 – Published: 8 October 2009 Abstract. Coastal hypoxia (defined here as <1.42 ml L−1; Mobile fish and shellfish will migrate away from low-oxygen 62.5 µM; 2 mg L−1, approx. 30% oxygen saturation) devel- areas. Within a species, early life stages may be more subject ops seasonally in many estuaries, fjords, and along open to oxygen stress than older life stages. coasts as a result of natural upwelling or from anthropogenic Hypoxia alters both the structure and function of benthic eutrophication induced by riverine nutrient inputs.