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Plant And Microbial Mechanisms Of Nitrogen Retention In Northern Hardwood Forests Receiving Atmospheric No3 Deposition
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Book Synopsis Plant and Microbial Mechanisms of Nitrogen Retention in Northern Hardwood Forests Receiving Atmospheric NO3 Deposition by : William C. Eddy
Download or read book Plant and Microbial Mechanisms of Nitrogen Retention in Northern Hardwood Forests Receiving Atmospheric NO3 Deposition written by William C. Eddy and published by . This book was released on 2006 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Elevated Atmospheric Nitrate Deposition in Northern Hardwood Forests by : Jared L. DeForest
Download or read book Elevated Atmospheric Nitrate Deposition in Northern Hardwood Forests written by Jared L. DeForest and published by . This book was released on 2004 with total page 216 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Nitrogen Cycling in the Northern Hardwood Forest by : Lucas Emil Nave
Download or read book Nitrogen Cycling in the Northern Hardwood Forest written by Lucas Emil Nave and published by . This book was released on 2007 with total page 89 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Nitrogen (N) is the nutrient most limiting to plant growth (NPP) in temperate forests. In N-limited temperate forests, most of the N required for NPP is recycled between soil and plant N pools by the microbial process of N-mineralization (Nmin). However, human activities have increased atmospheric N deposition (Ndep) to forests in the last 50-100 years, and this surplus N may increase NPP. But, forest responses to Ndep are not satisfactorily understood, and depend on how atmospheric N inputs are partitioned between soils and plants. From my field data collection at a mature forest site, I estimated that NPP required 51 kg N ha−1 yr−1, most of which was used for fine root and leaf production (62% and 31%, respectively). Each year, Nmin supplied 87% of Nreq, and Ndep contributed an additional 13%, 4% of which was due to canopy retention of Ndep (Ncr). Data from my mesocosm 15N-labelling experiment suggested that very little (10%) of Ncr observed in the field was actually taken up by trees, and the majority of Ndep (85%) was assimilated into soil pools. These results suggest that Ndep could not have significantly increased forest NPP at UMBS over the time scale of my studies. My greenhouse experiment corroborated this conclusion, with tree seedlings showing no significant increase in photosynthesis or growth in response to Ndep at ambient rates. However, Ndep to forest ecosystems has been occurring for decades in industrialized regions, and most of the N inputs have been incorporated into soil organic matter (SOM). Research across temperate forests has suggested that forests exposed to large N inputs over time exhibit decreased soil C/N ratios, which are associated with faster Nmin rates. Using meta-analysis, I verified this pattern in the literature, and discovered novel relationships between forest soil properties and their responses to N inputs. My results demonstrated a long-term, quantitative relationship between Ndep and Nmin, and suggest that NPP may increase in temperate forests affected by Ndep.
Book Synopsis Partitioning of Atmospheric Nitrogen Under Long-term Reduced Atmospheric Deposition Conditions in a Norway Spruce Forest Ecosystem by : Zhuo Feng
Download or read book Partitioning of Atmospheric Nitrogen Under Long-term Reduced Atmospheric Deposition Conditions in a Norway Spruce Forest Ecosystem written by Zhuo Feng and published by Universitätsverlag Göttingen. This book was released on 2010 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the past century, anthropogenic activities have increased N input drastically to terrestrial ecosystems and influenced the global N cycle. Especially temperate forest ecosystems are affected in their productivity, species composition, soil chemistry and water quality. N input to forest ecosystems is retained in trees and soil. Excessive N is leached out or released as gases. The retention of N input in soils is mainly influenced by the stability of soil organic matter (SOM). Many forests in central Europe and North America have been subjected to N saturation, i.e. excessive N appeared as nitrate in the leachate below the rooting zone. Reduction of atmospheric N emission and consequent atmospheric N deposition is proposed to be the only practical long-term solution to improve N-saturated forest ecosystems. However, responses of N-saturated forest ecosystems to reduced atmospheric N deposition have been seldom investigated. In the present study, atmospheric deposition was manipulated through roof constructions below the canopy of a mature Norway spruce forest on the Solling plateau in central Germany. A £^(5)N tracer field and a density fractionation laboratory experiment were conducted in the present study to investigate the influence of long-term reduced atmospheric N deposition on the partitioning of atmospheric N in different forest ecosystem compartments as well as on the partitioning of atmospheric N retained in the soil in different SOM pools.
Book Synopsis Nitrogen Loss from Northern Hardwood Forests Five Years Following Clear-cut Harvest by : Thomas M. Iseman
Download or read book Nitrogen Loss from Northern Hardwood Forests Five Years Following Clear-cut Harvest written by Thomas M. Iseman and published by . This book was released on 1997 with total page 33 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Plant and Microbial Controls on Nitrogen Retention and Loss in a Humid Tropical Forest by :
Download or read book Plant and Microbial Controls on Nitrogen Retention and Loss in a Humid Tropical Forest written by and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Humid tropical forests are generally characterized by the lack of nitrogen (N) limitation to net primary productivity, yet paradoxically have high potential for N loss. We conducted an intensive field experiment with 15NH4 and 15NO3 additions to highly weathered tropical forest soils to determine the relative importance of N retention and loss mechanisms. Over half of all the NH4 produced from gross mineralization was rapidly converted to NO3− during the process of gross nitrification. During the first 24 h plant roots took up 28 % of the N mineralized, dominantly as NH4, and were a greater sink for N than soil microbial biomass. Soil microbes were not a significant sink for added 15NH4+ or 15NO3− during the first 24 hr, and only for 15NH4+ after 7 d. Patterns of microbial community composition, as determined by Terminal Restriction Fragment Length Polymorphism analysis, were weakly, but significantly correlated with nitrification and denitrification to N2O. Rates of dissimilatory NO3− reduction to NH4+ (DNRA) were high in this forest, accounting for up to 25 % of gross mineralization and 35 % of gross nitrification. DNRA was a major sink for NO3− which may have contributed to the lower rates of N2O and leaching losses. Despite considerable N conservation via DNRA and plant NH4+ uptake, the fate of approximately 45% of the NO3− produced and 22% of the NH4+ produced were not measured in our fluxes, suggesting that other important pathways for N retention and loss (e.g., denitrification to N2) are important in this system. The high proportion of mineralized N that was rapidly nitrified and the fates of that NO3− highlight the key role of gross nitrification as a proximate control on N retention and loss in humid tropical forest soils. Furthermore, our results demonstrate the importance of the coupling between DNRA and plant uptake of NH4+ as a potential N conserving mechanism within tropical forests.
Book Synopsis The European Nitrogen Assessment by : Mark A. Sutton
Download or read book The European Nitrogen Assessment written by Mark A. Sutton and published by Cambridge University Press. This book was released on 2011-04-14 with total page 665 pages. Available in PDF, EPUB and Kindle. Book excerpt: Presenting the first continental-scale assessment of reactive nitrogen in the environment, this book sets the related environmental problems in context by providing a multidisciplinary introduction to the nitrogen cycle processes. Issues of upscaling from farm plot and city to national and continental scales are addressed in detail with emphasis on opportunities for better management at local to global levels. The five key societal threats posed by reactive nitrogen are assessed, providing a framework for joined-up management of the nitrogen cycle in Europe, including the first cost-benefit analysis for different reactive nitrogen forms and future scenarios. Incorporating comprehensive maps, a handy technical synopsis and a summary for policy makers, this landmark volume is an essential reference for academic researchers across a wide range of disciplines, as well as stakeholders and policy makers. It is also a valuable tool in communicating the key environmental issues and future challenges to the wider public.
Book Synopsis Direct and Indirect Effects of Tree Species on Forest Nitrogen Retention in the Catskill Mountains, New York by : Pamela Heather Templer
Download or read book Direct and Indirect Effects of Tree Species on Forest Nitrogen Retention in the Catskill Mountains, New York written by Pamela Heather Templer and published by . This book was released on 2001 with total page 119 pages. Available in PDF, EPUB and Kindle. Book excerpt: The aim of this research was to understand the influence of tree species on nitrogen (N) retention and cycling within forests of the Catskill Mountains, NY. These forests receive some of the highest rates of N deposition in the northeastern United States and many watersheds are beginning to show signs of N saturation. However, watersheds vary in the amount of N export even though they receive approximately uniform amounts of N deposition. I hypothesized that tree species of the Catskill Mountains vary in their influence on forest N retention and loss. Results from a laboratory study (Chapter 1) show that while tree species influence soil microbial biomass and organic soil C:N, the variation in these two properties cannot explain differences in potential net mineralization, net nitrification, or microbial uptake of 15N. Therefore, properties other than microbial biomass and soil C:N need to be examined to understand the factors controlling microbial N transformations and potential retention in these forest soils. A greenhouse experiment (Chapter 2) shows that sugar maple and hemlock seedlings take up more NH4 + than NO3-, while beech seedlings take up more NO3- than NH4 +. Results from a 300-day field 15N experiment (Chapter 3) show that most of the N deposited onto forests is retained within the forest floor, but the magnitude of N retention varies among tree species. Sugar maple stands retain the least N, while red oak stands retain the most. The fertilized treatment shows that red oak stands are most likely to have the greatest decrease in N retention if availability increases in the future. These results suggest that sugar maple stands currently export significantly more N than the other forested stands and this can be explained by a combination of soil and plant processes. Sugar maples are not able to take up a significant amount of NO 3- the form of N that is produced in the largest amount in their stands and is most susceptible to leaching losses. Results from this study suggest that tree species composition can be a strong regulator of forest N retention, and differences among species may change depending upon N inputs.
Book Synopsis A History of the Ecosystem Concept in Ecology by : Frank B. Golley
Download or read book A History of the Ecosystem Concept in Ecology written by Frank B. Golley and published by Yale University Press. This book was released on 1993-01-01 with total page 278 pages. Available in PDF, EPUB and Kindle. Book excerpt: The ecosystem concept--the idea that flora and fauna interact with the environment to form an ecological complex--has long been central to the public perception of ecology and to increasing awareness of environmental degradation. In this book an eminent ecologist explains the ecosystem concept, tracing its evolution, describing how numerous American and European researchers contributed to its evolution, and discussing the explosive growth of ecosystem studies. Golley surveys the development of the ecosystem concept in the late nineteenth and early twentieth centuries and discusses the coining of the term ecosystem by the English ecologist Sir Arthur George Tansley in 1935. He then reviews how the American ecologist Raymond Lindeman applied the concept to a small lake in Minnesota and showed how the biota and the environment of the lake interacted through the exchange of energy. Golley describes how a seminal textbook on ecology written by Eugene P. Odum helped to popularize the ecosystem concept and how numerous other scientists investigated its principles and published their results. He relates how ecosystem studies dominated ecology in the 1960s and became a key element of the International Biological Program biome studies in the United States--a program aimed at "the betterment of mankind" specifically through conservation, human genetics, and improvements in the use of natural resources; how a study of watershed ecosystems in Hubbard Brook, New Hampshire, blazed new paths in ecosystem research by defining the limits of the system in a natural way; and how current research uses the ecosystem concept. Throughout Golley shows how the ecosystem concept has been shaped internationally by both developments in other disciplines and by personalities and politics.
Book Synopsis The Environmental Chemistry of Aluminum by : Garrison Sposito
Download or read book The Environmental Chemistry of Aluminum written by Garrison Sposito and published by CRC Press. This book was released on 2020-04-08 with total page 477 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Environmental Chemistry of Aluminum provides a comprehensive, fundamental account of the aqueous chemistry of aluminum within an environmental context. An excellent reference for environmental chemists and scientific administrators of environmental programs, this book contains material reflecting the many recent changes in this rapidly developing discipline. The first three chapters discuss the most fundamental aspects of aluminum chemistry: its quantitation in soils and natural waters, including speciation measurements, and its stable chemical forms, both as a dissolved solute and in a solid phase. These chapters emphasize both critical assessments of and definitive recommendations for laboratory methodologies and measured thermodynamic properties relating to aluminum chemistry. The next four chapters in The Environmental Chemistry of Aluminum build on this foundation to provide details of the polymeric chemistry of aluminum: its polynuclear and colloidal hydrolytic species in aqueous solution, its complexes with natural organic ligands, including humic substances, and its role as an adsorptive and adsorbent in surface reactions. These chapters are grounded in experimental results rather than conceptual modeling. The final three chapters describe the chemistry of aluminum in soils, waters, and watersheds. These chapters illustrate the problems of spatial and temporal variability, metastability, and scale that continue to make aluminum geochemistry one of the great challenges in modern environmental science.
Book Synopsis British Plant Communities by : J. S. Rodwell
Download or read book British Plant Communities written by J. S. Rodwell and published by Cambridge University Press. This book was released on 1998-04-30 with total page 644 pages. Available in PDF, EPUB and Kindle. Book excerpt: British Plant Communities is the first systematic and comprehensive account of the vegetation types of this country. It covers all natural, semi-natural and major artificial habitats in Great Britain (but not Northern Ireland), representing the fruits of fifteen years of research by leading plant ecologists. The book breaks new ground in wedding the rigorous interest in the classification of plant communities that has characterized Continental phytosociology with the deep concern traditional in Great Britain to understand how vegetation works. The published volumes have been greeted with universal acclaim, and the series has become firmly established as a framework for a wide variety of teaching, research and management activities in ecology, conservation and land-use planning.
Book Synopsis Effects of Nitrogen and Shosphorus Addition on Soil Respiration in Northern Hardwood Forests by : Shiyi Li
Download or read book Effects of Nitrogen and Shosphorus Addition on Soil Respiration in Northern Hardwood Forests written by Shiyi Li and published by . This book was released on 2018 with total page 56 pages. Available in PDF, EPUB and Kindle. Book excerpt: Soil respiration - the CO2 efflux from the forest soil surface - is an important indicator of root and microbial activity and is sensitive to global changes such as climate warming, anthropogenic nitrogen deposition and elevated atmospheric CO2. I evaluated the response of total soil respiration (TSR) to changes in soil nutrient availability in temperate deciduous forests in New Hampshire. Low-level N (3 g/m2/year), P (1 g/m2/year) or N + P have been applied annually to thirteen northern hardwood stands of different age and site quality since 2011. My analysis of TSR for 2013, 2014, 2016, and 2017 confirmed the overall suppression effect of N addition across these stands (p
Book Synopsis Soil Processes and the Carbon Cycle by : Rattan Lal
Download or read book Soil Processes and the Carbon Cycle written by Rattan Lal and published by CRC Press. This book was released on 2018-02-06 with total page 632 pages. Available in PDF, EPUB and Kindle. Book excerpt: World soils contain about 1500 gigatons of organic carbon. This large carbon reserve can increase atmospheric concentrations of CO2 by soil misuse or mismanagement, or it can reverse the 'greenhouse' effect by judicious land use and proper soil management. Soil Processes and the Carbon Cycle describes soil processes and their effects on the global carbon cycle while relating soil properties to soil quality and potential and actual carbon reserves in the soil. In addition, this book deals with modeling the carbon cycle in soil, and with methods of soil carbon determinations.
Book Synopsis Clean Coastal Waters by : National Research Council
Download or read book Clean Coastal Waters written by National Research Council and published by National Academies Press. This book was released on 2000-08-17 with total page 422 pages. Available in PDF, EPUB and Kindle. Book excerpt: Environmental problems in coastal ecosystems can sometimes be attributed to excess nutrients flowing from upstream watersheds into estuarine settings. This nutrient over-enrichment can result in toxic algal blooms, shellfish poisoning, coral reef destruction, and other harmful outcomes. All U.S. coasts show signs of nutrient over-enrichment, and scientists predict worsening problems in the years ahead. Clean Coastal Waters explains technical aspects of nutrient over-enrichment and proposes both immediate local action by coastal managers and a longer-term national strategy incorporating policy design, classification of affected sites, law and regulation, coordination, and communication. Highlighting the Gulf of Mexico's "Dead Zone," the Pfiesteria outbreak in a tributary of Chesapeake Bay, and other cases, the book explains how nutrients work in the environment, why nitrogen is important, how enrichment turns into over-enrichment, and why some environments are especially susceptible. Economic as well as ecological impacts are examined. In addressing abatement strategies, the committee discusses the importance of monitoring sites, developing useful models of over-enrichment, and setting water quality goals. The book also reviews voluntary programs, mandatory controls, tax incentives, and other policy options for reducing the flow of nutrients from agricultural operations and other sources.
Book Synopsis Ecosystems of California by : Harold Mooney
Download or read book Ecosystems of California written by Harold Mooney and published by Univ of California Press. This book was released on 2016-01-19 with total page 1008 pages. Available in PDF, EPUB and Kindle. Book excerpt: This long-anticipated reference and sourcebook for CaliforniaÕs remarkable ecological abundance provides an integrated assessment of each major ecosystem typeÑits distribution, structure, function, and management. A comprehensive synthesis of our knowledge about this biologically diverse state, Ecosystems of California covers the state from oceans to mountaintops using multiple lenses: past and present, flora and fauna, aquatic and terrestrial, natural and managed. Each chapter evaluates natural processes for a specific ecosystem, describes drivers of change, and discusses how that ecosystem may be altered in the future. This book also explores the drivers of CaliforniaÕs ecological patterns and the history of the stateÕs various ecosystems, outlining how the challenges of climate change and invasive species and opportunities for regulation and stewardship could potentially affect the stateÕs ecosystems. The text explicitly incorporates both human impacts and conservation and restoration efforts and shows how ecosystems support human well-being. Edited by two esteemed ecosystem ecologists and with overviews by leading experts on each ecosystem, this definitive work will be indispensable for natural resource management and conservation professionals as well as for undergraduate or graduate students of CaliforniaÕs environment and curious naturalists.
Book Synopsis Drinking Water from Forests and Grasslands by :
Download or read book Drinking Water from Forests and Grasslands written by and published by . This book was released on 2000 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis The Fernow Watershed Acidification Study by : Mary Beth Adams
Download or read book The Fernow Watershed Acidification Study written by Mary Beth Adams and published by BoD – Books on Demand. This book was released on 2006-04-28 with total page 298 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Fernow Watershed Acidification Study is a long-term, paired watershed acidification study. This book describes the responses to chronic N and S amendments by deciduous hardwood forests, one of the few studies to focus on hardwood forest ecosystems. Intensive monitoring of soil solution and stream chemistry, along with measurements of soil chemistry, and vegetation growth and chemistry, provide insights into the acidification process in forested watersheds.
