Topic
Wetland
About: Wetland is a research topic. Over the lifetime, 26317 publications have been published within this topic receiving 586887 citations.
Papers published on a yearly basis
Papers
More filters
TL;DR: It is found that the reported long-term loss of natural wetlands averages between 54–57% but loss may have been as high as 87% since 1700 AD, and there has been a much faster rate of wetland loss during the 20th and early 21st centuries.
Abstract: It has been frequently stated, but without provision of supporting evidence, that the world has lost 50% of its wetlands (or 50% since 1900 AD). This review of 189 reports of change in wetland area finds that the reported long-term loss of natural wetlands averages between 54–57% but loss may have been as high as 87% since 1700 AD. There has been a much (3.7 times) faster rate of wetland loss during the 20th and early 21st centuries, with a loss of 64–71% of wetlands since 1900 AD. Losses have been larger and faster for inland than coastal natural wetlands. Although the rate of wetland loss in Europe has slowed, and in North America has remained low since the 1980s, the rate has remained high in Asia, where large-scale and rapid conversion of coastal and inland natural wetlands is continuing. It is unclear whether the investment by national governments in the Ramsar Convention on Wetlands has influenced these rates of loss. There is a need to improve the knowledge of change in wetland areas worldwide, particularly for Africa, the Neotropics and Oceania, and to improve the consistency of data on change in wetland areas in published papers and reports.
1,209 citations
TL;DR: In this article, the authors summarized how macrophytes influence the treatment processes in wetlands and concluded that the most important functions of the macrophyte in relation to the treatment of wastewater are the physical effects the presence of the plants gives rise to.
1,071 citations
TL;DR: A global data base of wetlands at 1° resolution has been developed from the integration of three independent global, digital sources: vegetation, soil properties and fractional inundation in each 1° cell as discussed by the authors.
Abstract: A global data base of wetlands at 1° resolution has been developed from the integration of three independent global, digital sources: (1) vegetation, (2) soil properties and (3) fractional inundation in each 1° cell. The integration yielded a global distribution of wetland sites identified with in situ ecological and environmental characteristics. The wetland sites have been classed into five major wetland groups on the basis of environmental characteristics governing methane emissions. The global wetland area derived in this study is ∼5.3 × 1012m2, approximately twice the wetland area previously used in methane-emission studies. Methane emission was calculated using methane fluxes for the major wetland groups, and simple assumptions about the duration of the methane production season. The annual methane emission from wetlands is ∼110 Tg, well within the range of previous estimates (11-300 Tg). Tropical/subtropical peat-poor swamps from 20°N-30°S account from ∼30% of the global wetland area and ∼25% of the total methane emission. About 60% of the total emission comes from peat-rich bogs concentrated from 50°-7O°N, suggesting that the highly seasonal emission from these ecosystems is the major contributor to the large annual oscillations observed in atmospheric methane concentrations at these latitudes.
1,061 citations
TL;DR: It is suggested that the overall carbon budget of rainforests, summed across terrestrial and aquatic environments, appears closer to being in balance than would be inferred from studies of uplands alone.
Abstract: Terrestrial ecosystems in the humid tropics play a potentially important but presently ambiguous role in the global carbon cycle. Whereas global estimates of atmospheric CO2 exchange indicate that the tropics are near equilibrium or are a source with respect to carbon, ground-based estimates indicate that the amount of carbon that is being absorbed by mature rainforests is similar to or greater than that being released by tropical deforestation (about 1.6 Gt C yr-1). Estimates of the magnitude of carbon sequestration are uncertain, however, depending on whether they are derived from measurements of gas fluxes above forests or of biomass accumulation in vegetation and soils. It is also possible that methodological errors may overestimate rates of carbon uptake or that other loss processes have yet to be identified. Here we demonstrate that outgassing (evasion) of CO2 from rivers and wetlands of the central Amazon basin constitutes an important carbon loss process, equal to 1.2 +/- 0.3 Mg C ha-1 yr-1. This carbon probably originates from organic matter transported from upland and flooded forests, which is then respired and outgassed downstream. Extrapolated across the entire basin, this flux-at 0.5 Gt C yr-1-is an order of magnitude greater than fluvial export of organic carbon to the ocean. From these findings, we suggest that the overall carbon budget of rainforests, summed across terrestrial and aquatic environments, appears closer to being in balance than would be inferred from studies of uplands alone.
1,010 citations
Book•
28 Jul 2008TL;DR: For example, in the state of Louisiana, the Everglades watershed has been identified as one of the most important areas for the development of biogeochemical properties of wetlands as discussed by the authors.
Abstract: Introduction Basic Concepts and Terminology Chemistry Microbiology and Biochemistry Isotopes Terminology in Soil Science Units Biogeochemical Characteristics of Wetlands Types of Wetlands Wetland Hydrology Wetland Soils Wetland Vegetation Biogeochemical Features of Wetlands Types of Wetland/Hydric Soils Field Indicators of Hydric Soils Electrochemical Properties Theoretical Relationships Measurement of Eh Eh-pH Relationships Buffering of Redox Potential (Poise) Measurement of Redox Potentials pH Redox Couples in Wetlands Redox Gradients in Soils Microbial Fuel Cells Specific Conductance Carbon Major Components of Carbon Cycle in Wetlands Organic Matter Accumulation Characteristics of Detritus and Soil Organic Matter Decomposition Organic Matter Turnover Regulators of Organic Matter Decomposition Environmental and Ecological Significance Functions of Organic Matter in Soils Oxygen Oxygen-H2O Redox Couple Soil Gases Sources of Oxygen Aerobic-Anaerobic Interfaces Oxygen Consumption Adaptation of Plants to Soil Anaerobiosis Distribution of Wetland Plants Mechanisms of Flood Tolerance Mechanisms of Oxygen Movement in Wetland Plants Oxygen Release by Plants Measurement of Radial Oxygen Loss Soil Phytotoxic Accumulation Effects on Plant Growth Oxidizing Power of Plant Roots Effect of Intensity and Capacity of Soil Reduction on Wetland Plant Functions .000 Nitrogen Forms of Nitrogen Major Storage Compartments Redox Transformations of Nitrogen Mineralization of Organic Nitrogen Ammonia Adsorption-Desorption Ammonia Fixation Ammonia Volatilization Nitrification Anaerobic Ammonium Oxidation Nitrate Reduction Nitrogen Fixation Nitrogen Assimilation by Vegetation Nitrogen Processing by Wetlands Phosphorous Phosphorus Accumulation in Wetlands Phosphorus Forms in Water Column and Soil Inorganic Phosphorus Phosphorus Sorption by Soils Organic Phosphorus Phosphorus Uptake and Storage in Biotic Communities Mineralization of Organic Phosphorus Biotic and Abiotic Interactions on Phosphorus Mobilization Phosphorus Exchange between Soil and Overlying Water Column .000 Phosphorus Memory by Soils and Sediments Biogeochemistry of Iron and Manganese Storage and Distribution Eh-pH Relationships Reduction of Iron and Manganese Oxidation of Iron and Manganese Mobility of Iron and Manganese Ecological Significance Sulfur Major Storage Compartments Forms of Sulfur Oxidation-Reduction of Sulfur Assimilatory Sulfate and Elemental Sulfur Reduction Mineralization of Organic Sulfur Electron Acceptor-Reduction of Inorganic Sulfur Electron Donor-Oxidation of Sulfur Compounds Biogenic Emission of Reduced Sulfur Gases Sulfur-Metal Interactions Sulfi de Toxicity Exchange between Soil and Water Column Sulfur Sinks Metals/Metalloids Factors Governing Metal Availability and Transformation .000 Mercury-Methyl Mercury Arsenic Chemical Oxidation and Reduction of Arsenic Copper Zinc Selenium Chromium Cadmium Lead Nickel Toxic Organic Compounds Biotic Pathways Metabolism of Organic Compounds Plant and Microbial Uptake Abiotic Pathways Regulators Soil and Floodwater Exchange Processes Advective Flux Diffusive Flux Bioturbation Wind Mixing and Resuspension Exchange of Dissolved Solutes between Soil/Sediment and the Water Column .000 Sediment Transport Processes Vegetative Flux/Detrital Export Air-Water Exchange 40 Biogeochemical Regulation of Exchange Processes Biogeochemical Indicators Concept of Indicators Guidelines for Indicator Development Levels of Indicators Wetland Ecosystem Reference Conditions Sampling Protocol and Design Data Analysis Wetlands and Global Climate Change Potential Impact of Global Change to Wetlands Methane Nitrous Oxide Carbon Sequestration Impact of Sea-Level Rise on Coastal Wetlands Freshwater Wetlands: The Everglades Everglades Wetlands Nutrient Loads and Ecological Alternations Biogeochemical Cycles Restoration and Recovery Coastal Wetlands: Mississippi River Deltaic Plain Coastal Marshes, Louisiana Biogeography and Geology of Louisiana Coastal Wetlands Coastal Wetland Loss Case Studies Impact of Flooding and Saltwater Intrusion on Louisiana Coastal Vegetation Carbon Cycling Nitrogen Cycling Sulfur Cycling Case Studies of Factors Governing the Fate of Toxic Organic Compounds and Pollutants in the Louisiana Coastal Wetland Advances in Biogeochemistry Biogeochemical Processes Algal and Microbial Interactions Vegetation and Microbial Interactions Modern Tools to Study Biogeochemical Cycles Synthesis: Mechanistic and Statistical Models Future Directions and Perspectives References Index *Each chapter contains an Introduction, Summary, References, and suggestions for Further Readings. Most chapters also contain Study Questions.
1,006 citations