Read Books Online and Download eBooks, EPub, PDF, Mobi, Kindle, Text Full Free.
Improving Dndc Modeling Capability To Quantify Mitigation Potential Of Nitrous Oxide From California Agricultural Soils
Download Improving Dndc Modeling Capability To Quantify Mitigation Potential Of Nitrous Oxide From California Agricultural Soils full books in PDF, epub, and Kindle. Read online Improving Dndc Modeling Capability To Quantify Mitigation Potential Of Nitrous Oxide From California Agricultural Soils ebook anywhere anytime directly on your device. Fast Download speed and no annoying ads. We cannot guarantee that every ebooks is available!
Book Synopsis Improving DNDC Modeling Capability to Quantify Mitigation Potential of Nitrous Oxide from California Agricultural Soils by : Changsheng Li
Download or read book Improving DNDC Modeling Capability to Quantify Mitigation Potential of Nitrous Oxide from California Agricultural Soils written by Changsheng Li and published by . This book was released on 2017 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Soil Emission of Nitrous Oxide and its Mitigation by : David Ussiri
Download or read book Soil Emission of Nitrous Oxide and its Mitigation written by David Ussiri and published by Springer. This book was released on 2012-11-12 with total page 378 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nitrous oxide gas is a long-lived relatively active greenhouse gas (GHG) with an atmospheric lifetime of approximately 120 years, and heat trapping effects about 310 times more powerful than carbon dioxide per molecule basis. It contributes about 6% of observed global warming. Nitrous oxide is not only a potent GHG, but it also plays a significant role in the depletion of stratospheric ozone. This book describes the anthropogenic sources of N2O with major emphasis on agricultural activities. It summarizes an overview of global cycling of N and the role of nitrous oxide on global warming and ozone depletion, and then focus on major source, soil borne nitrous oxide emissions. The spatial-temporal variation of soil nitrous oxide fluxes and underlying biogeochemical processes are described, as well as approaches to quantify fluxes of N2O from soils. Mitigation strategies to reduce the emissions, especially from agricultural soils, and fertilizer nitrogen sources are described in detail in the latter part of the book.
Book Synopsis Understanding Greenhouse Gas Emissions from Agricultural Management by : Lei Guo
Download or read book Understanding Greenhouse Gas Emissions from Agricultural Management written by Lei Guo and published by OUP USA. This book was released on 2012-04-19 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: A valuable source of information for researchers and environmental practitioners, providing the most up-to-date information on greenhouse gas emissions from field crops and livestock animals
Book Synopsis Nitrous Oxide Emissions from California Tomato Cropping Systems Under Conventional and Alternative Management by : Taryn Lee Kennedy
Download or read book Nitrous Oxide Emissions from California Tomato Cropping Systems Under Conventional and Alternative Management written by Taryn Lee Kennedy and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Primarily associated with soil fertility management practices, nitrous oxide (N2O) is a potent greenhouse gas (GHG) whose emission from farmland is a concern for environmental quality and agricultural productivity. In California, agriculture and forestry account for 8% of the total GHG emissions, of which 50% is accounted for by N2O (CEC, 2005). Furrow irrigation and high temperatures in the Central Valley, together with conventional fertilization, are ideal for the production of food, but also N2O production. These conditions can promote N2O emissions, but also suggest great potential to reduce N2O emissions by optimizing fertilizer and irrigation management. Smaller, more frequent fertilizer applications increase the synchrony between available soil nitrogen (N) and crop N uptake and may result in less N loss to the atmosphere. Given that the ecosystem processes regulating the production of N2O respond to and interact with multiple factors influenced by environmental and managerial conditions, it is not always feasible to approach the study of integrated agricultural systems and their affect on GHG emissions by use of a factorial experiment alone. On-farm studies are therefore an important precursor to research station trials to determine which management practices and components of a complete management system should be targeted and isolated for future study. Farm-based trials also provide a realistic evaluation of current management practices subject to practical and economic constraints. The following study took place on existing farms in order to assess the effect of active, operational farm field conditions and current managements on GHG emissions and to thoroughly characterize two typical management systems. In this study, I determined how management practices, such as fertilization, irrigation, tillage, and harvest, affect direct N2O emissions in tomato cropping systems under two contrasting irrigation managements and their associated fertilizer application method, i.e. furrow irrigation and knife injection (conventional system) versus drip irrigation, reduced tillage, and fertigation (integrated system). Field sites were located on two farms in close proximity, on the same soil type, and were planted with the same crop cultivar. This project demonstrated that shifts in fertilizer and irrigation water management directly affect GHG emissions. More fertilizer was applied in the conventional system (237 kg N ha−1 growing season−1) than the integrated system (205 kg N ha−1 growing season−1). The amount of irrigated water was comparable between the two systems; 64 to 70 cm was applied in the conventional system and 64 cm in the integrated system. Total weighted growing season emissions were 3.4 times greater in the conventional system (2.39 ± 0.17 kg N2O-N ha−1) than the integrated system (0.58 ± 0.06 kg N2O-N ha−1), with a higher tomato yield in the integrated system (131 vs. 86 Mg ha−1). The highest conventional N2O emissions resulted from fertilization plus irrigation events and the first fall precipitation. In the integrated system, the highest N2O fluxes occurred following harvest and the first fall precipitation. Environmental parameters of soil moisture, soil mineral N, and dissolved organic carbon (DOC) were higher and more spatially variable in the conventional system. Reduced N2O emissions in the integrated system, resulting from low soil moisture, mineral N concentrations, and DOC levels, imply that improved fertilizer and water management strategies can be effective in mitigating greenhouse gas emissions from agriculture.
Book Synopsis Evaluating Mitigation Options of Nitrous Oxide Emissions in California Cropping Systems by : Martin Burger
Download or read book Evaluating Mitigation Options of Nitrous Oxide Emissions in California Cropping Systems written by Martin Burger and published by . This book was released on 2016 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Measured and Daycent- Simulated Nitrous Oxide Emissions from Soil Planted to Corn in Dairy Cropping Systems by : Maria Ponce De Leon Jara
Download or read book Measured and Daycent- Simulated Nitrous Oxide Emissions from Soil Planted to Corn in Dairy Cropping Systems written by Maria Ponce De Leon Jara and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Crop rotations, organic nutrient amendments, reduced tillage practices, and integration of cover crops are practices that have the potential to increase the sustainability of crop production, yet they also impact nitrous oxide (N2O) emissions. Agricultural soil management has been estimated to contribute 79% of the total N2O emissions in the U.S., and inorganic nitrogen (N) fertilization is one of the main contributors. Nitrous oxide is a potent greenhouse gas that has a global warming potential which is approximately 298 times that of carbon dioxide (CO2) over a 100-year period and is currently the dominant ozone-depleting substance. Few studies have assessed the effects of organic N amendments on direct N2O within the context of a typical dairy forage cropping system. Most research has been limited to studying the effects of one or two sources of N inputs on N2O emissions; however, dairy forage cropping systems often apply manure and have more than two N sources that likely both contribute to N2O emissions. This study investigated how different dairy cropping practices that include differences in crop residues, N inputs (dairy manure and inorganic fertilizer), timing of N amendment applications and environmental conditions influenced N2O emissions from no-till soil planted to corn (Zea mays L.). A two-year field study was carried out as part of the Pennsylvania State Sustainable Dairy Cropping Systems Experiment, where corn was planted following annual grain crops, perennial forages, and a green manure legume crop; all were amended with dairy manure. In the corn-soybean (Glycine max (L.) Merr.) rotation, N sources (dairy manure and inorganic fertilizer) and two methods of manure application (broadcasted and injected) were also compared.Chapter 1 reviews the scientific literature; describing the biotic and abiotic processes of N2O production in soils, summarizing current research on N2O emissions in agricultural systems, and emphasizing the main management and environmental drivers contributing to the emissions. This chapter reviews methods for matching N supply with crop demand, coupling N flow cycles, using advanced fertilizer techniques, and optimizing tillage management. Also, the applicability and limitations of current research to effectively reduce N2O emissions in a variety of regions are discussed.Chapter 2 analyzes the effect of corn production management practices and environmental conditions contributing to N2O in the Pennsylvania State Sustainable Dairy Cropping Systems Experiment. Significantly higher N2O emissions were observed 15-42 days after manure injection and 1-4 days after mid-season UAN application. Manure injection had 2-3 times greater potential for N2O emissions compared to broadcast manure during this time period. Integration of legumes and grasses in the cropping system reduced inorganic fertilizer use compared to soybean with manure or UAN, however, direct N2O emissions were not reduced. The Random Forest method was used to identify and rank the predictor variables for N2O emissions. The most important variables driving N2O emissions were: time after manure application, time after previous crop termination, soil nitrate, and moisture. These field research results support earlier recommendations for reducing N losses including timing N inputs close to crop uptake, and avoiding N applications when there is a high chance of precipitation to reduce nitrate accumulation in the soil and potential N losses from denitrification.Chapter 3 reports the comparison of N2O fluxes predicted with the biogeochemical model DAYCENT compared to measured data from the two-year dairy cropping systems study. Daily N2O emissions simulated by DAYCENT had between 41% and 76% agreement with measured daily N2O emissions in 2015 and 2016. DAYCENT overestimated the residual inorganic N fertilizer impact on N2O emissions in the corn following soybean with inorganic fertilizer and broadcast manure. Comparisons between DAYCENT simulated and measured N2O fluxes indicate that DAYCENT did not represent well organic N amendments from crop residues of perennials and legume cover crops, or manure application in no-till dairy systems. DAYCENT was generally able to reproduce temporal patterns of soil temperature, but volumetric soil water contents (VSWC) predicted by DAYCENT were generally lower than measured values. After precipitation events, DAYCENT predicted that VSWC tended to rapidly decrease and drain to deeper layers. Both the simulated and measured soil inorganic N increased with N fertilizer addition; however, the model tended to underestimate soil inorganic N concentration in the 0-5 cm layer. Our results suggest that DAYCENT overestimated the residual N impact of inorganic fertilizer on N2O emissions and mineralization of organic residues and nitrification happened faster than DAYCENT predicted. Chapter 4 highlights the impact of manure injection and the importance of timing organic N amendments from manures and/or crop residue with crop N uptake to mitigate N2O emissions. More research is needed to better understand the tradeoffs of these strategies in no till dairy cropping systems to help farmers in their operational management decisions. Improving the parametrization of DAYCENT for dairy cropping systems in no-till systems with high surface legume crop residues from perennials and cover crops, will make the model a more useful tool for testing different mitigation scenarios for farmers and policy-designer decision making.
Book Synopsis Soil Nitrous Oxide Emissions from Agriculture in a Changing Global Environment by : Charlotte Decock
Download or read book Soil Nitrous Oxide Emissions from Agriculture in a Changing Global Environment written by Charlotte Decock and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Agricultural soils encompass one of the major sources of anthropogenic nitrous oxide (N2O), a potent greenhouse gas and stratospheric ozone depleting substance. Therefore, accurate prediction of N2O emissions from soils and development of effective mitigation strategies are pertinent. However, the scientific understanding of mechanisms underlying N2O emissions is limited, in part, by the lack of suitable methods to assess sources of N2O, especially under field conditions and in undisturbed soil cores. In this dissertation, two ecological applications of source-partitioning N2O were considered: (1) the feedback of N2O emissions to elevated atmospheric CO2 and tropospheric O3 and (2) mechanisms underlying N2O emissions during a simulated rainfall event in a tomato cropping system in California. Furthermore, four methods were evaluated for their utility in source-partitioning N2O with minimal disturbance of the system: (1) tracing of added 15N enriched NH4 and/or NO3− to N2O, (2) use of natural abundance 15N of N2O and its precursors, (3) measuring the intramolecular distribution of 15N in N2O, expressed as site preference (SP), and (4) determining relationships between natural abundance 18O and 15N. Method comparisons elucidated that the use of isotope models that include all natural abundance isotopes of N2O and its precursors and uncertainty deductions for isotope fractionation factors to estimate N transformation rates and sources of N2O during peak N2O emissions is the most promising approach to improve our understanding of mechanisms underlying N2O emissions with minimal sampling-associated disturbance of the system. Various approaches to study sources of N2O and N-cycling suggested that elevated CO2 and O3 will unlikely cause a feedback on global climate change through altered N2O emissions in soybean agroecosystems in the Midwestern USA. Furthermore, elevated CO2 decelerated, whereas elevated O3 accelerated N-cycling if integrated over longer time scales. In a California tomato cropping system, N2O reduction to N2 decreased progressively as soil dried out following wetting up. Overall, this dissertation illustrates the added benefit of studying mechanisms underlying N2O emissions in addition to field N2O fluxes per se and encourages further research to source-partition N2O emissions and its needed methodology to understand N2O responses of agroecosystems in a changing global environment.
Book Synopsis Mitigation of Nitrous Oxide Emissions During Nitrification and Denitrification Processes in Agricultural Soils Using Enhanced Efficiency Fertilizers by : Yoshitaka Uchida
Download or read book Mitigation of Nitrous Oxide Emissions During Nitrification and Denitrification Processes in Agricultural Soils Using Enhanced Efficiency Fertilizers written by Yoshitaka Uchida and published by . This book was released on 2018 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Through the increasing use of nitrogen (N) fertilizers due to an increasing food demand, the agricultural sector is the main contributor of anthropogenic nitrous oxide (N2O) emissions, mainly through microbial processes called nitrification and denitrification. One option to mitigate N2O, a major greenhouse gas, is to use enhanced efficiency fertilizers (EEFs). There are different types of EEFs like nitrification inhibitors or controlled-release fertilizers that aim to match the N release from fertilizers with N demands from plants. Parts of the chapter are also dedicated to organic amendments and their effects on N2O emissions. Overall, EEFs can improve the N-use efficiency of plants, which has two positive effects. First, farmers can increase their yields, and second, environmental pollution through excessive fertilizer N can be minimized. However, the effectiveness of EEFs strongly depends on numerous factors like land use type, application method, and climate. More studies are needed to establish individual fertilizer plans that are optimized for the prevalent conditions. In conclusion, N2O mitigation using EEFs is only advisable when ,Äúinitial,Äù N2O emissions from conventional fertilizers are critically contributing to annual N2O emissions. Thus, careful assessment is needed before EEFs are introduced to the system especially when economic and ecologic results are considered.
Book Synopsis Methods for Measuring Greenhouse Gas Balances and Evaluating Mitigation Options in Smallholder Agriculture by : Todd S. Rosenstock
Download or read book Methods for Measuring Greenhouse Gas Balances and Evaluating Mitigation Options in Smallholder Agriculture written by Todd S. Rosenstock and published by Springer. This book was released on 2016-08-23 with total page 217 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides standards and guidelines for quantifying greenhouse gas emissions and removals in smallholder agricultural systems and comparing options for climate change mitigation based on emission reductions and livelihood trade-offs. Globally, agriculture is directly responsible for about 11% of annual greenhouse gas (GHG) emissions and induces an additional 17% through land use change, mostly in developing countries. Farms in the developing countries of sub-Saharan Africa and Asia are predominately managed by smallholders, with 80% of land holdings smaller than ten hectares. However, little to no information exists on greenhouse gas emissions and mitigation potentials in smallholder agriculture. Greenhouse gas measurements in agriculture are expensive, time consuming, and error prone, challenges only exacerbated by the heterogeneity of smallholder systems and landscapes. Concerns over methodological rigor, measurement costs, and the diversity of approaches, coupled with the demand for robust information suggest it is germane for the scientific community to establish standards of measurements for quantifying GHG emissions from smallholder agriculture. Standard guidelines for use by scientists, development organizations will help generate reliable data on emissions baselines and allow rigorous comparisons of mitigation options. The guidelines described in this book, developed by the CGIAR Research Program on Climate Change, Agriculture, and Food Security (CCAFS) and partners, are intended to inform anyone conducting field measurements of agricultural greenhouse gas sources and sinks, especially to develop IPCC Tier 2 emission factors or to compare mitigation options in smallholder systems.
Book Synopsis Process Modeling of Global Soil Nitrous Oxide Emissions by : Eri Saikawa
Download or read book Process Modeling of Global Soil Nitrous Oxide Emissions written by Eri Saikawa and published by . This book was released on 2011 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nitrous oxide is an important greenhouse gas and is a major ozone-depleting substance. To understand and quantify soil nitrous oxide emissions, we expanded the Community Land Model with prognostic Carbon and Nitrogen (CLM-CN) by inserting a module to estimate annually- and seasonally-varying nitrous oxide emissions between 1978 and 2000. We evaluate our soil N2O emission estimates against existing emissions inventories, other process-based model estimates, and observations from two forest sites in the Amazon and one in the United States. The model reproduces soil temperature and soil moisture relatively well, and it reconfirms the important relationship between N2O emissions and these parameters. The model also reproduces observations of N2O emissions well in the Amazonian forests but not during the winter in the USA. Applying this model to estimate the past 23 years of global soil N2O emissions, we find that there is a significant decrease in soil N2O emissions associated with drought and El Niño years. More study is necessary to quantify the high-latitude winter activity in the model in order to better understand the impact of future climate on N2O emissions and vice versa.
Book Synopsis Mitigation of Greenhouse Gas Emissions in Livestock Production by : Pierre J. Gerber
Download or read book Mitigation of Greenhouse Gas Emissions in Livestock Production written by Pierre J. Gerber and published by Food & Agriculture Organization of the UN (FAO). This book was released on 2013 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt: The current analysis was conducted to evaluate the potential of nutritional, manure and animal husbandry practices for mitigating methane (CH4) and nitrous oxide (N2O) - i.e. non-carbon dioxide (CO2) - GHG emissions from livestock production. These practices were categorized into enteric CH4, manure management and animal husbandry mitigation practices. Emphasis was placed on enteric CH4 mitigation practices for ruminant animals (only in vivo studies were considered) and manure mitigation practices for both ruminant and monogastric species. Over 900 references were reviewed; simulation and life cycle assessment analyses were generally excluded
Book Synopsis Nitrous Oxide Emissions from Agricultural Soil Receiving Manure in a Changing Climate by : Chih-Yu Hung
Download or read book Nitrous Oxide Emissions from Agricultural Soil Receiving Manure in a Changing Climate written by Chih-Yu Hung and published by . This book was released on 2021 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: "Soil nitrous oxide (N2O) emission varies in magnitude and occurs sporadically during the spring freeze-thaw period in cold humid temperate regions. Fluctuations in soil N2O emissions are related to soil biophysical properties, which are influenced by agricultural practices like fall application of manure and fall-sown cover crops, as well as rainfall and other weather events. The objectives of this thesis were to (1) quantify N2O emissions in the spring period from agricultural soils that received manure and were planted with a cover crop in the previous fall, (2) estimate the influence of fall-applied manure and cover crops on the spring soil N2O emissions in changing climate, (3) determine the biophysical factors that control soil N¬2O emissions after a rain-induced thawing event, and (4) propose a monitoring method to estimate N2O emissions in agricultural soils. First, I quantified the soil N2O emissions with a two-year field experiment. Soil N2O emission in the spring freeze-thaw period (c.a. 30 d) was -2.35 to 13.57 g N ha-1 and not affected by dairy manure application (solid or liquid) or cover crops (ryegrass and ryegrass/hairy vetch), possibly due to the low manure N application rate and N loss over winter. Second, I evaluated soil N2O emissions in the spring freeze-thaw period under three climate scenarios (baseline, from 1981–2010; Representative Concentration Pathway 4.5 and 8.5 from 2071–2100) with the Decomposition-Denitrification model. The model predicted that more reactive N will be retained by cover crops under future climate scenarios, but the soil N2O emissions will not increase. However, applying solid manure without a cover crop led to more soil N2O emissions than other treatments tested under three climate scenarios (9.90 to 61.50 g N ha-1, P
Book Synopsis Soil Carbon Dynamics by : Werner L. Kutsch
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.
Book Synopsis Simulating Changes in Soil Organic Carbon in Bangaladesh with the Denitrification-decomposition (DNDC) Model by : Syeda Rubyat Shahid
Download or read book Simulating Changes in Soil Organic Carbon in Bangaladesh with the Denitrification-decomposition (DNDC) Model written by Syeda Rubyat Shahid and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Developed countries' growing awareness of greenhouse gas (CO2, CH4, N2O) emissions from agricultural soils has led to an increased interest in the management of soil organic matter (SOM), which now extends to developing countries, including Bangladesh. Bangladeshi agriculture follows a largely rice-based cropping rotation, for which insufficient site-specific information regarding gas emissions exists to identify temporal variability of SOM content. The objective of this study was to evaluate the applicability of the 'Denitrification-Decomposition' model (DNDC, version 9.3) as a tool to better understand SOC trends in tropical agriculture. DNDC was used to simulate gas emissions from 1948 to 1969 and 1981 to 2007, under farm management practices prevalent in the Dinajpur district of Bangladesh. Forty-nine years of historical daily precipitation and temperature data were used for simulation with DNDC, such that both aerobic and anaerobic conditions were experience...
Book Synopsis Spatio-temporal Variation of Denitrification Drivers by : Lia Shrewsbury
Download or read book Spatio-temporal Variation of Denitrification Drivers written by Lia Shrewsbury and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 Soil Erosion and Carbon Dynamics by : Eric J. Roose
Download or read book Soil Erosion and Carbon Dynamics written by Eric J. Roose and published by CRC Press. This book was released on 2005-12-09 with total page 499 pages. Available in PDF, EPUB and Kindle. Book excerpt: The most complete, nonpartisan source of information on this hot agronomic topic available today, this book brings together a diverse group of papers and data to resolve the debate between sedimentologists and soil scientists and agronomists over whether the effects of soil erosion on carbon and atmospheric CO2 is beneficial or destructive. Divided into four sections, it offers data on how soil erosion affects soil, water, and air quality. Topics include mineralization rate, inundation, sediment deposition, and global warming potential, as well as carbon dioxide, methane, and nitrous oxide emissions, and the implications of soil erosion on the global carbon cycle and carbon budget.
