Tài liệu Global Change and the Function and Distribution of Wetlands ppt

Global Change and the Function and Distribution of Wetlands Global Change Ecology and Wetlands Volume 1 Published in collaboration with the Society of Wetland Scientists – Global Change Ecology Section The Society of Wetland Scientists’ book series, Global Change Ecology and Wetlands, emerged from the Society’s Global Change Ecology Section. There is a growing need among wetlands managers and scientists to address problems of climate change in wetlands, and this series will fi ll an important literature gap in the fi eld of global change as it relates to wetlands around the world. The goal is to highlight the latest research from the world leaders researching climate change in wetlands, to disseminate research fi ndings on global change ecology, and to provide sound science to the public for decision-making on wetland policy and stewardship. Each volume will address a topic addressed by the annual symposium of the Society’s Global Change Ecology Section. For further volumes: http://www.springer.com/series/8905 Beth A. Middleton Editor Global Change and the Function and Distribution of Wetlands Editor Beth A. Middleton National Wetlands Research Center US Geological Survey Lafayette, LA, USA ISBN 978-94-007-4493-6 ISBN 978-94-007-4494-3 (eBook) DOI 10.1007/978-94-007-4494-3 Springer Dordrecht Heidelberg New York London Library of Congress Control Number: 2012942468 Chapters 2 and 4: © The U.S. Government’s right to retain a non-exclusive, royalty-free licence in and to any copyright is acknowledged 2012 © Springer Science+Business Media Dordrecht 2012 This work is subject to copyright. All rights are reserved by the Publisher, whether the whole or part of the material is concerned, speci fi cally the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on micro fi lms or in any other physical way, and transmission or information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed. Exempted from this legal reservation are brief excerpts in connection with reviews or scholarly analysis or material supplied speci fi cally for the purpose of being entered and executed on a computer system, for exclusive use by the purchaser of the work. Duplication of this publication or parts thereof is permitted only under the provisions of the Copyright Law of the Publisher’s location, in its current version, and permission for use must always be obtained from Springer. Permissions for use may be obtained through RightsLink at the Copyright Clearance Center. Violations are liable to prosecution under the respective Copyright Law. The use of general descriptive names, registered names, trademarks, service marks, etc. in this publication does not imply, even in the absence of a speci fi c statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. While the advice and information in this book are believed to be true and accurate at the date of publication, neither the authors nor the editors nor the publisher can accept any legal responsibility for any errors or omissions that may be made. The publisher makes no warranty, express or implied, with respect to the material contained herein. Printed on acid-free paper Springer is part of Springer Science+Business Media (www.springer.com) v Contents Part I Paleoecology and Climate Change Insights from Paleohistory Illuminate Future Climate Change Effects on Wetlands 3 Ben A. LePage, Bonnie F. Jacobs, and Christopher J. Williams Part II Sea Level Rise and Coastal Wetlands Response of Salt Marsh and Mangrove Wetlands to Changes in Atmospheric CO 2 , Climate, and Sea Level 63 Karen McKee, Kerrylee Rogers, and Neil Saintilan Part III Atmospheric Emissions and Wetlands Key Processes in CH 4 Dynamics in Wetlands and Possible Shifts with Climate Change 99 Hojeong Kang, Inyoung Jang, and Sunghyun Kim Part IV Drought and Climate Change The Effects of Climate-Change-Induced Drought and Freshwater Wetlands 117 Beth A. Middleton and Till Kleinebecker Index 149 Part I Paleoecology and Climate Change 3 B.A. Middleton (ed.), Global Change and the Function and Distribution of Wetlands, Global Change Ecology and Wetlands 1, DOI 10.1007/978-94-007-4494-3_1, © Springer Science+Business Media Dordrecht 2012 Abstract Climate change could have profound impacts on world wetland environments, which can be better understood through the examination of ancient wetlands when the world was warmer. These impacts may directly alter the critical role of wetlands in ecosystem function and human services. Here we present a framework for the study of wetland fossils and deposits to understand the potential effects of future climate change on wetlands. We review the methods and assump- tions associated with the use of plant macro- and microfossils to reconstruct ancient wetland ecosystems and their associated paleoenvironments. We then present case studies of paleo-wetland ecosystems under global climate conditions that were very different from the present time. Our case study of extinct Arctic forested-wetlands reveals insights about high-productivity wetlands that fl ourished in the highest lati- tudes during the ice-free global warmth of the Paleogene (ca. 45 million years ago) and how these wetlands might have been instrumental in keeping the polar regions warm. We then evaluate climate-induced changes in tropical wetlands by focusing on the Pleistocene and Holocene (2.588 Myr ago to the present) of Africa. These past B. A. LePage (*) Academy of Natural Sciences , 1900 Benjamin Franklin Parkway , Philadelphia , PA 19103 , USA PECO Energy Company , 2301 Market Street, S7-2 , Philadelphia , PA 19103 , USA e-mail: ben.lepage@exeloncorp.com B. F. Jacobs Roy M. Huf fi ngton Department of Earth Sciences , Southern Methodist University , P.O. Box 750395 , Dallas , TX 75275-0395 , USA e-mail: bjacobs@smu.edu C. J. Williams Department of Earth and Environment , Franklin and Marshall College , P.O. Box 3003 , Lancaster , PA 17604-3003 , USA e-mail: chris.williams@fandm.edu Insights from Paleohistory Illuminate Future Climate Change Effects on Wetlands Ben A. LePage , Bonnie F. Jacobs , and Christopher J. Williams 4 B.A. LePage et al. ecosystems demonstrate that subtle changes in the global energy balance had signi fi cant impacts on global hydrology and climate, which ultimately determine the composition and function of wetland ecosystems. Moreover, the history of these regions demonstrates the inter-connectedness of the low and high latitudes, and the global nature of the Earth’s hydrologic cycle. Our case studies provide glimpses of wetland ecosystems, which expanded and ultimately declined under a suite of global climate conditions with which humanity has little if any experience. Thus, these paleoecology studies paint a picture of future wetland function under projected global climate change. 1 Introduction Virtually every aspect of the planet Earth, especially climate, has changed over the last four billion years. There is no reason to believe that these changes will cease, or more to the point, that we can stop such changes because they are now impacting our daily lives. From a geological point of view, global climate change is inevitable, and we need to ask ourselves whether our efforts to curb such change is likely to have the desired mitigating effect? While the solution is complicated and certainly cannot be answered within the context of this chapter, our goal is to help put global climate change into a geological perspective with respect to wetlands. When Earth’s history is viewed in a geological context, we see a planet that has always been in a state of geologic and geomorphologic fl ux. The Earth’s climate has changed considerably throughout geologic time and ironically, we live at one of the few times when global climate is cold, or what geologists call “icehouse conditions”. For most of Earth’s history “hothouse or greenhouse conditions” prevailed, ice caps were absent, and the average global temperature was considerably warmer than at present. The consensus among scientists is the anthropogenic input of greenhouse gases to the atmosphere, particularly carbon dioxide (CO 2 ), have triggered a phase of global warming (Solomon et al . 2007 ; Rosenzweig et al . 2008 ) . The pace and inten- sity of future warming and the associated signi fi cant environmental changes are likely to be governed, in part, by anthropogenic greenhouse gas inputs. What then can the study of ancient wetland communities, some from millions of years ago, offer to understand better the effects of future climate change on wet- lands? It is important that we frame our discussion of wetland impacts in the context of world wetland extent. The current global wetland area is estimated to be approxi- mately 12.8 million square kilometers (km 2 ) or 8.6% of the total land area of the world (Schuyt and Brander 2004 ) . In an ice-free world, the total wetland area could double in size to 25 million km 2 (18% of the total land area) if we assume that at least 50% of the area currently classi fi ed as ice (Greenland and Antarctica) and tundra would become wetland and the current wetland area of 12.8 million km 2 would be maintained. This assumption seems reasonable judging from the geo- graphic extent and amount of Cenozoic-age (Fig. 1 ; 65.5 to 2.588 million years old [Myr]) coals in northern and Arctic Canada, Iceland, Spitsbergen, Alaska, and Russia. 5Insights from Paleohistory Illuminate Future Climate Change Effects on Wetlands Berriasian Valanginian Hauterivian Barremian Aptian Albian Lower Upper Cenomanian Turonian Coniacian Santonian Campanian Maastrichtian Danian Selandian Thanetian Ypresian Lutetian Bartonian Priabonian Rupelian Chattian Paleocene Eocene Oligocene Miocene Pliocene Pleistocene Holocene Tarentian Ionian Calabrian Gelasian Piacenzian Zanclean Messinian Tortonian Serravallian Langhian Burdigalian Aquitanian Quaternary Neogene Paleogene Cretaceous Mesozoic Phanerozoic Eonothem Eon Erathem Era System Period Series Epoch Stage Age Calibrated Age (Myr) 0.0117 0.130 0.781 1.806 2.588 3.600 5.332 7.246 11.608 13.82 15.97 20.43 23.03 28.4 33.9 37.2 40.4 48.6 55.8 58.7 61.1 65.5 70.6 83.5 85.8 88.6 93.6 99.6 112.0 125.0 130.0 133.9 142.2 145.5 Cenozoic Fig. 1 Stratigraphic chart showing the ages in millions of years (Myr) of the geologic periods and epochs. The ages follow those adopted by the International Commission on Stratigraphy ( 2010 ) [...]... to wetlands is most likely an underestimate Nevertheless, global climate change will considerably increase the area of wetlands on the planet and these wetlands will undoubtedly have significant impacts on future climate change, carbon and nutrient cycling, and biodiversity This chapter is focused on insights that can be garnered from the past that help us understand the impact of global climate change. .. environmental change because of the resistance of pollens and spores to decay, and their ubiquity and abundance (Traverse 2008) Wetlands are excellent sources of pollen and spores and like macrofossils, palynomorph assemblages provide information useful in the reconstruction of past environments Palynomorphs are likely to disperse farther than plant macrofossils because of their small size and thus more often... et al These coal deposits indicate large areas of moderately productive wetlands extended from 50°N to the pole in the Northern Hemisphere throughout the Paleogene and Neogene (Bustin 1981; Bustin and Miall 1991; Kalkreuth et al 1993) Therefore, most of the 11.5 million km2 of area currently classified as tundra may become wetland during future climate change so the 50% estimate of the conversion of tundra... hundreds of years) for sediments that are millions of years old, the local and regional patterns of vegetation change can still be interpreted in the context of climate and environmental change 18 B.A LePage et al From the standpoint of interpreting future climate change, the use of pollen and spores provides scientists with the greatest amount of data given that most sedimentary deposits contain pollen and. .. information at the regional, rather than at the local scale Nevertheless, the spatial resolution of the pollen flora is strongly influenced by the size and nature of the depositional setting (e.g., lake versus bog) and the relevant source area (Sugita 1993, 1994) More importantly, pollen and spores are often preserved in places where plant macrofossils are not, thereby providing another potential source of Fig... Geochemistry is the study of the distribution of chemical elements and natural compounds on the Earth Geochemical approaches used in the study of plant fossils help determine the original chemical composition, deposition, burial, and thermal maturity of the fossil tissues, as well as the nature of chemical transformations in the paleoenvironment (van Bergen 1999) Studies aimed at better understanding the chemical... considerable time and effort is being focused on global environmental change and its effects on biodiversity in the tropical regions, the polar regions (particularly the Arctic) stand to suffer the greatest changes due to polar amplification of global temperature change (Holland and Bitz 2003; Peacock et al 2011) Since 1980, the polar regions have experienced the most rapid warming on the planet of about 1°C... the most fundamental to the climate change discussion is understanding of the structure and function of Arctic wetlands under global hothouse climate conditions The lack of modern analogues (i.e., forested Arctic) as well as our lack of historic experience with the changes associated with a transition Fig 20 An idealized stratigraphic column showing the typical stratigraphy associated with a foreland... part of a much broader regional vegetation mosaic of ecological communities including upland, fluvial, bottomland, and swamp forests The sandstone deposits are the remnants of ancient fluvial systems that bisected the bottomland and swamp forests (Fig 22) Abrasion-resistant organs such as seed cones, nuts, and pieces of wood of the plants are commonly preserved in sand (Figs 8–10) The siltstone and mudstone... bottomland forest deposits showing vertical accretion of the floodplains was occurring along with changes in the regional landscape Although there is no evidence of a complete turnover in the bottomland forest composition at Napartulik, the local environmental changes would have likely had an impact on the frequency and abundance of the local flora, providing the region with a floral mosaic Fig 24 View of the . Global Change and the Function and Distribution of Wetlands Global Change Ecology and Wetlands Volume 1 Published in collaboration with the Society of. Paleoecology and Climate Change 3 B.A. Middleton (ed.), Global Change and the Function and Distribution of Wetlands, Global Change Ecology and Wetlands 1,