Download Free Influence Of Wetland Dynamics On Microbial Redox Transformations Of Nitrate And Iron Book in PDF and EPUB Free Download. You can read online Influence Of Wetland Dynamics On Microbial Redox Transformations Of Nitrate And Iron and write the review.

Wetlands provide valuable ecosystem functions including nutrient recycling, carbon storage, flood mitigation, and habitat in support of biodiversity. However, land use change and climate change stressors continue to threaten wetland ecosystems. Specifically, climate change is predicted to increase rates of sea-level rise and increase frequency of storm surges. Therefore, we need to better understand how the combined saltwater intrusion and flooding environmental stressors influence coastal wetland structure and function. Environmental stressors modify soil redox potential which directly influences microbial community structure and function in ways that alter transformations of carbon, nitrogen, sulfur, and iron, at the ecosystem level. Abiotic and biotic factors, including hydrology and plant presence, can affect terminal electron acceptor availability and dictate rates and types of metabolic microbial functions to different degrees. In a previous experiment, a soil mesocosm approach was used to examine how hydrology (wet, dry, interim) and plant presence (with or without plants) influenced wetland soils sampled from varying hydrologic histories (wet, dry, interim) in a restored, coastal wetland. After eight weeks of hydrologic manipulation, 16S rRNA amplicon sequencing and shotgun metagenomic sequencing were performed to characterize the microbial communities and greenhouse gas concentrations were measured to assess microbial function. Soil redox potential and soil physicochemical properties were also measured. Previous results showed that plant presence decreased greenhouse gas concentrations even in flooded conditions, and hydrology (history and contemporary treatment) altered wetland soil microbial community structure and the composition of carbohydrate metabolic genes. Functional genes involved in methanogenesis, and aerobic respiration, also differed in composition across hydrologic histories. In this study, we address the questions (1) how do hydrologic and plant related redox shifts relate to the composition of metabolic genes involved in sulfur/iron cycling and (2) how do patterns of iron-sulfur metabolic composition relate to carbon and nitrogen metabolic composition and greenhouse gas production? We hypothesized that the most reducing conditions (i.e., prolonged flooded, no plants) modify anaerobic metabolisms in similar ways. We predict that (i) in oxidizing conditions (dry and/or plant presence), functional gene composition of sulfate reduction will not correlate to the gene composition of iron reduction, and (ii) in reducing conditions (i.e., wet and/or plant absence), functional gene composition of sulfate reduction will correlate to patterns in iron reduction metabolic genes. In addition, iron and sulfur metabolic gene composition will contribute to carbon dioxide production while competing with methanogenesis. Results revealed that hydrologic treatment impacted assimilatory sulfate reduction gene composition, while hydrologic history impacted dissimilatory sulfate reduction composition. Hydrologic history significantly affected total iron active gene composition and iron reduction gene composition. We also identified correlations between sulfate reduction and iron reduction, especially in flooded conditions, while sulfate reduction and iron reduction compositions explained variation in biogenic greenhouse gas concentrations (carbon dioxide and methane). These results demonstrate the role of historical hydrology, saltwater exposure, and soil iron in shaping microbial community responses to future changes in hydrology and plant cover. Salinization events (e.g., saltwater intrusion) and changing precipitation patterns impact soil redox dynamics by altering sulfate and oxygen availability, and challenge estimates of biogenic greenhouse gas emissions. Therefore, a better understanding of microbial community responses to hydrologic manipulations, plant presence/absence, and soil physicochemistry will inform wetland greenhouse gas emissions predictions and management strategies (e.g., plant presence and hydrologic flows).
At present, constructed wetlands for wastewater treatment are a widely used technology for treatment of various types of wastewaters. The International Water Association (then International Association on Water Pollution Research and Control) recognized wetlands as useful tools for wastewater treatment and est- lished the series of biennial conferences on the use of wetland systems for water pollution control in 1988. In about 1993, we decided to organize a workshop on nutrient cycling in natural and constructed wetlands with the major idea to bring together researchers working on constructed and also natural wetlands. It was not our intention to compete with IWA conferences, but the workshop should rather complement the series on treatment wetlands by IWA. We believed that the exchange of information obtained from natural and constructed wetlands would be beneficial for all participants. And the time showed that we were correct. The first workshop took place in 1995 at T?ebo? in South Bohemia and most of the papers dealt with constructed wetlands. Over the years we extended the topics on natural wetlands (such as role of wetlands in the landscape or wetland restoration and creation) and during the 6th workshop held at T?ebo? from May 30 to June 3, 2006, nearly half of 38 papers presented during the workshop dealt with natural wetlands. This workshop was attended by 39 participants from 19 countries from Europe, Asia, North and South Americas and Australia. The volume contains 29 peer-reviewed papers out of 38 papers which were presented during the workshop.
The globally important nature of wetland ecosystems has led to their increased protection and restoration as well as their use in engineered systems. Underpinning the beneficial functions of wetlands are a unique suite of physical, chemical, and biological processes that regulate elemental cycling in soils and the water column. This book provides an in-depth coverage of these wetland biogeochemical processes related to the cycling of macroelements including carbon, nitrogen, phosphorus, and sulfur, secondary and trace elements, and toxic organic compounds. In this synthesis, the authors combine more than 100 years of experience studying wetlands and biogeochemistry to look inside the black box of elemental transformations in wetland ecosystems. This new edition is updated throughout to include more topics and provide an integrated view of the coupled nature of biogeochemical cycles in wetland systems. The influence of the elemental cycles is discussed at a range of scales in the context of environmental change including climate, sea level rise, and water quality. Frequent examples of key methods and major case studies are also included to help the reader extend the basic theories for application in their own system. Some of the major topics discussed are: Flooded soil and sediment characteristics Aerobic-anaerobic interfaces Redox chemistry in flooded soil and sediment systems Anaerobic microbial metabolism Plant adaptations to reducing conditions Regulators of organic matter decomposition and accretion Major nutrient sources and sinks Greenhouse gas production and emission Elemental flux processes Remediation of contaminated soils and sediments Coupled C-N-P-S processes Consequences of environmental change in wetlands# The book provides the foundation for a basic understanding of key biogeochemical processes and its applications to solve real world problems. It is detailed, but also assists the reader with box inserts, artfully designed diagrams, and summary tables all supported by numerous current references. This book is an excellent resource for senior undergraduates and graduate students studying ecosystem biogeochemistry with a focus in wetlands and aquatic systems.
Concerns regarding heavy metal contamination in terrestrial ecosystems have prompted increasing efforts on limiting their bioavailability in the root zone. The complexity of the hydrologic system gives rise to the need for understanding the fate and transport of trace elements in the soil-water-plant environment. Dynamics and Bioavailability of Hea
Water quality and management are of great significance globally, as the demand for clean, potable water far exceeds the availability. Water science research brings together the natural and applied sciences, engineering, chemistry, law and policy, and economics, and the Treatise on Water Science seeks to unite these areas through contributions from a global team of author-experts. The 4-volume set examines topics in depth, with an emphasis on innovative research and technologies for those working in applied areas. Published in partnership with and endorsed by the International Water Association (IWA), demonstrating the authority of the content Editor-in-Chief Peter Wilderer, a Stockholm Water Prize recipient, has assembled a world-class team of volume editors and contributing authors Topics related to water resource management, water quality and supply, and handling of wastewater are treated in depth
Bridging the fields of ecosystem science and landscape ecology, this book integrates Dr. Carol Johnston's research on beaver ecosystem alteration at Voyageurs National Park. The findings about the vegetation, soils, and chemistry of beaver impoundments synthesized in the text provide a cohesive reference useful to wetland scientists, ecosystems and landscape ecologysts, wildlife managers, and students. The beaver, Castor canadensis, is an ecosystem engineer unequaled in its capacity to alter landscapes through browsing and dam building, whose population recovery has re-established environmental conditions that probably existed for millenia prior to its near extirpation by trapping in the 1800s and 1900s. Beavers continue to regain much of their natural range throughout North America, changing stream and forest ecosystems in ways that may be lauded or vilified. Interest in beavers by ecologists remains keen as new evidence emerges about the ecological, hydrological, and biogeochemical effects of beaver browsing and construction. There is a critical need for ecologists and land managers to understand the potential magnitude, persistence, and ecosystem services of beaver landscape transformation. The 88-year record of beaver landscape occupation and alteration documented by Dr. Carol Johnston and colleagues from aerial photography and field work provides a unique resource toward understanding the ecosystem effects and sustainability of beaver activity.