Download or read book Quantitative Comparison of in Situ Soil CO2 Flux Measurement Methods written by Jennifer D. Knoepp and published by . This book was released on 2002 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Quantitative Comparison of in Situ Soil COb2s Flux Measurement Methods written by Jennifer D. Knoepp and published by . This book was released on 2002 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: Development of reliable regional or global carbon budgets requires accurate measurement of soil CO2 flux. We conducted laboratory and field studies to determine the accuracy and comparability of methods commonly used to measure in situ soil CO2 fluxes. Methods compared included CO2 traps; a multichamber open dynamic system (OC) with an infrared gas analyzer; and a headspace analysis system, with gas chromatograph with circulating fan (GCF) and gas chromatograph without circulating fan (GC), measuring changes in headspace CO2 concentration using a gas chromatograph. In the laboratory, we compared NaOH, OC, GCF, and GC using sand-filled cylinders to simulate a soil system. Three concentrations of standard CO2 gas (representing low, medium, and high soil-CO2 flux rates) entered the cylinders through individually monitored flow meters. Flux rates measured using the OC method equaled the actual CO2 flux at all three CO2 concentrations. Flux rates determined with GC and GCF were 55 percent of the actual flux rate. The percent of actual CO2 flux measured increased with increasing CO2 concentrations. At all concentrations, NaOH collected between 40 and 47 percent of CO2 entering the system. A field study was conducted to verify laboratory results and allow comparison with the soda lime trap (SODA) method. In laboratory and field studies, all methods detected significant differences in flux rates among the standard CO2 concentrations and field sites. Regression analyses showed good relationships between NaOH, SODA, and GC methods with flux rates measured using the OC methods (r2 = 0.78). Slope values for these regression equations ranged from 0.34 for NaOH to 0.54 for GC and SODA. These results suggest that data collected using the other methods could be standardized to OC flux rates. However, because methodological differences significantly affect CO2 flux measurements, care should be used in applying these relationships.
Download or read book Quantitative Comparison of in Situ Soil CO2 Flux Measurement Methods written by Jennifer D. Knoepp and published by . This book was released on 2002 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Research Paper SRS written by and published by . This book was released on 1996 with total page 208 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Methods of Measuring Environmental Parameters written by Yuriy Posudin and published by John Wiley & Sons. This book was released on 2014-08-07 with total page 464 pages. Available in PDF, EPUB and Kindle. Book excerpt: Provides a systematic review of modern methods and instruments for measuring environmental parameters • Profiles the most modern methods and instruments for environment control and monitoring • Gives an assessment of biotic and abiotic factors and their effect on quality of atmosphere and indoor air, soil, water • Provides a brief description of the main climatic (pressure, wind, temperature, humidity, precipitation, solar radiation), atmospheric, hydrographic, and edaphic factors • Covers a wide range environmental methods and instrumentation including those used in the fields of meteorology, air pollution, water quality, soil science and more • Supplied with practical exercises, problems, and tests that will help the reader to learn more deeply contents of the book
Download or read book Comparative Soil CO2 Flux Measurements and Geostatisticalestimation Methods on Masaya Volcano Nicaragua written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: We present a comparative study of soil CO2 flux (F{sub CO2}) measured by five groups (Groups 1-5) at the IAVCEI-CCVG Eighth Workshop on Volcanic Gases on Masaya volcano, Nicaragua. Groups 1-5 measured F{sub CO2} using the accumulation chamber method at 5-m spacing within a 900 m2 grid during a morning (AM) period. These measurements were repeated by Groups 1-3 during an afternoon (PM) period. All measured F{sub CO2} ranged from 218 to 14,719 g m−2d−1. Arithmetic means and associated CO2 emission rate estimates for the AM data sets varied between groups by ±22%. The variability of the five measurements made at each grid point ranged from ±5 to 167% and increased with the arithmetic mean. Based on a comparison of measurements made by Groups 1-3 during AM and PM times, this variability is likely due in large part to natural temporal variability of gas flow, rather than to measurement error. We compared six geostatistical methods (arithmetic and minimum variance unbiased estimator means of uninterpolated data, and arithmetic means of data interpolated by the multiquadric radial basis function, ordinary kriging, multi-Gaussian kriging, and sequential Gaussian simulation methods) to estimate the mean and associated CO2 emission rate of one data set and to map the spatial F{sub CO2} distribution. While the CO2 emission rates estimated using the different techniques only varied by ±1.1%, the F{sub CO2} maps showed important differences. We suggest that the sequential Gaussian simulation method yields the most realistic representation of the spatial distribution of F{sub CO2} and is most appropriate for volcano monitoring applications.
Download or read book Canadian Journal of Forest Research written by and published by . This book was released on 2008 with total page 876 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Forest Soils Research Theory Reality and Its Role in Technology Transfer written by Margaret Gale and published by Gulf Professional Publishing. This book was released on 2005-12-21 with total page 354 pages. Available in PDF, EPUB and Kindle. Book excerpt: This collection represents a unique set of essays on the role of theory in shaping the practice of medicine across disciplinary boundaries. In the context of this volume, "theory” relates to the conceptual models, frameworks, knowledge representations, metaphors and analogies that inform the problem-solving efforts of practitioners seeking to develop novel dialogues both within and across disciplinary boundaries. Contributors to this volume include computational scientists, chemists, medical researchers, biologists and philosophers, all drawing on personal experience in their respective fields to produce a genuinely interdisciplinary range of perspectives on the common theme of theory in medical thinking and multidisciplinary research practice. * Selected and edited papers from the 10th North American Forest Soils Conference held in Saulte Ste. Marie, Ontario, Canada, July 20-24, 2003 * A unique spin-off from Elsevier's highly regarded journal, Forest Ecology and Management * An estimated 400 pages of the latest findings in forest soil ecology from the most prominent researchers in the field
Download or read book Soil Respiration and the Environment written by Luo Yiqi and published by Elsevier. This book was released on 2010-07-20 with total page 334 pages. Available in PDF, EPUB and Kindle. Book excerpt: The global environment is constantly changing and our planet is getting warmer at an unprecedented rate. The study of the carbon cycle, and soil respiration, is a very active area of research internationally because of its relationship to climate change. It is crucial for our understanding of ecosystem functions from plot levels to global scales. Although a great deal of literature on soil respiration has been accumulated in the past several years, the material has not yet been synthesized into one place until now. This book synthesizes the already published research findings and presents the fundamentals of this subject. Including information on global carbon cycling, climate changes, ecosystem productivity, crop production, and soil fertility, this book will be of interest to scientists, researchers, and students across many disciplines. A key reference for the scientific community on global climate change, ecosystem studies, and soil ecology Describes the myriad ways that soils respire and how this activity influences the environment Covers a breadth of topics ranging from methodology to comparative analyses of different ecosystem types The first existing "treatise" on the subject
Download or read book Methods of Soil Analysis Part 2 written by Richard W. Weaver and published by ACSESS. This book was released on 1994 with total page 1164 pages. Available in PDF, EPUB and Kindle. Book excerpt: Soil sampling for microbiological analysis; Statistical treatment of microbial data; Soil sterilization; Soil water potencial; Most probable number counts; Light microscopic methods for studying soil microorganisms; Viruses; Recovery and enumeration of viable bacteria; Coliform bacteria; Autotrophic nitrifying bacteria; Free-living dinitrogen-fixing bacteria; Legume nodule symbionts; Anaerobic bacteria and processes; Denitrifiers; Actiomycetes; Frankia and the actinorhizal symbiosis; Filamentous fungi; Vesicular-arbuscular mycorrhizal fungi; Isolation of microorganisms producting antibiotics; Microbiological procedures for biodegradation research; Algae and cyanobacteria; Marking soil bacteria with lacZY; Detection of specific DNA sequences in environmental sample via polymerase chaim reaction; Isolation and purification of bacterial DNA from soil; Microbial biomass; Soil enzymes; Carbon mineralization; Isotopic methods for the study of soil organic matter dynamics ; Practical considerations in the use of nitrogen tracers in agricultural and environmental research; Nitrogen availability; Nitrogen mineralization, immobilization, and nitrification; Dinitrogen fixation; Measuring denitrification in the field; Sulfur oxidation and reduction in soils; Iron and manganese oxidation and reduction.
Download or read book Soil Carbon Dynamics written by Werner L. Kutsch and published by Cambridge University Press. This book was released on 2010-01-07 with total page 301 pages. Available in PDF, EPUB and Kindle. Book excerpt: Carbon stored in soils represents the largest terrestrial carbon pool and factors affecting this will be vital in the understanding of future atmospheric CO2 concentrations. This book provides an integrated view on measuring and modeling soil carbon dynamics. Based on a broad range of in-depth contributions by leading scientists it gives an overview of current research concepts, developments and outlooks and introduces cutting-edge methodologies, ranging from questions of appropriate measurement design to the potential application of stable isotopes and molecular tools. It includes a standardised soil CO2 efflux protocol, aimed at data consistency and inter-site comparability and thus underpins a regional and global understanding of soil carbon dynamics. This book provides an important reference work for students and scientists interested in many aspects of soil ecology and biogeochemical cycles, policy makers, carbon traders and others concerned with the global carbon cycle.
Download or read book Improving Characterization of Anthropogenic Methane Emissions in the United States written by National Academies of Sciences, Engineering, and Medicine and published by National Academies Press. This book was released on 2018-08-25 with total page 251 pages. Available in PDF, EPUB and Kindle. Book excerpt: Understanding, quantifying, and tracking atmospheric methane and emissions is essential for addressing concerns and informing decisions that affect the climate, economy, and human health and safety. Atmospheric methane is a potent greenhouse gas (GHG) that contributes to global warming. While carbon dioxide is by far the dominant cause of the rise in global average temperatures, methane also plays a significant role because it absorbs more energy per unit mass than carbon dioxide does, giving it a disproportionately large effect on global radiative forcing. In addition to contributing to climate change, methane also affects human health as a precursor to ozone pollution in the lower atmosphere. Improving Characterization of Anthropogenic Methane Emissions in the United States summarizes the current state of understanding of methane emissions sources and the measurement approaches and evaluates opportunities for methodological and inventory development improvements. This report will inform future research agendas of various U.S. agencies, including NOAA, the EPA, the DOE, NASA, the U.S. Department of Agriculture (USDA), and the National Science Foundation (NSF).
Download or read book Das Dammkultur System nach Turiel written by Evelyn Müller and published by kassel university press GmbH. This book was released on 2010 with total page 105 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Plant Respiration Metabolic Fluxes and Carbon Balance written by Guillaume Tcherkez and published by Springer. This book was released on 2018-02-20 with total page 302 pages. Available in PDF, EPUB and Kindle. Book excerpt: There are currently intense efforts devoted to understand plant respiration (from genes toecosystems) and its regulatory mechanisms; this is because respiratory CO2 productionrepresents a substantial carbon loss in crops and in natural ecosystems. Thus, in addition tomanipulating photosynthesis to increase plant biomass production, minimization ofrespiratory loss should be considered in plant science and engineering. However, respiratorymetabolic pathways are at the heart of energy and carbon skeleton production and therefore, itis an essential component of carbon metabolism sustaining key processes such asphotosynthesis. The overall goal of this book is to provide an insight in such interactions aswell as an up-to-date view on respiratory metabolism, taking advantage of recent advancesand concepts, from fluxomics to natural isotopic signal of plant CO2 efflux. It is thus a nonoverlapping,complement to Volume 18 in this series (Plant Respiration From Cell toEcosystem) which mostly deals with mitochondrial electron fluxes and plant-scale respiratorylosses.
Download or read book Applied Mechanics Reviews written by and published by . This book was released on 1993 with total page 354 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nuclear Science Abstracts written by and published by . This book was released on 1974 with total page 692 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Soil Salinity Assessment written by J. D. Rhoades and published by Food & Agriculture Org.. This book was released on 1999 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt: Determination of soil salinity from aqueous electrical conductivity; determination of soil salinity from soil-paste and bulk soil electrical conductivity; example uses of salinity assessment technology; operational and equipment costs associated with salinity instrumentation measurement techniques.