Download or read book Soil N Mineralization as Affected by Abiotic Factors and Tillage Systems written by Eileen Joyce Kladivko and published by . This book was released on 1982 with total page 468 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Organic Nitrogen Mineralization and Nitrous Oxide Production by Soil Microorganisms written by Deifallah M. Daoud and published by . This book was released on 1984 with total page 334 pages. Available in PDF, EPUB and Kindle. Book excerpt: The effect of soil water on net soil organic N mineralization (Nmin) under aerobic (sinal de maior sobre sinal de menor) Nitrapyrin and anaerobic (N2 atm) conditions was evaluated in the laboratory with a silt loam soil incubated at 30oC. Nmin increased with increasing soil water under aerobic ( -5 to -0.08 bar water potential) and anaerobic ( -0.3 to 0.0 bar) conditions and was a function of soil water per se rather than electron acceptor evailability. Indirect evidence indicate that decreased N2 loss by denitrification in the presence of Nitrapyrin was due in part to the reduced O2 demand resulting from NH 4 (sinal de maior sobre o 4) oxidation inhibition. 111-defined decreases in efficiency of nitrification inhibition in the saturated soil water range complicates use of Nitrapyrin for estimating Nmin under concurrent nitrification/denitricfication conditions. Enviromental factors affecting N2O production by soil nitrifiers were evaluated under equilibrium (carrying capacity, K-phase) NH 4 (sinal de maior e do menor sobre o 4) oxidizing conditions in pH 7.5- and NH4 (sinal de maior sobre o 4) pool size (?2 mM) -controlled liquid culture. Following attainment of self-regulated steady state rates of NH4 (sinal de maior sobre o 4) consumption under constant aeration (>5 to 0.2% dissolved oxygen, DOT) and temperature (10 to 30oC) conditions, cultures of soil microorganisms were subjected to O2, temperature, and NO2 (sinal do menor sobre o 2) perturbations. YN2 O-N (% of NH 4 sinal de maior sobre o 4-N consumed released as N2 O-N) was generaly -0.3% under a wide range of constant and intermittently perturbed aeration (0.3 to 10% DOT), temperature (10 to 20oC) and NO 2 (sinal de menor sobre o 2) 810 TO 1500 micron M) conditions. Steadyn state YN2 O-N under 0.2% DOT(22 sinal de maior sobre sinal de menor3o.C) was 1.1 (sinal de maior sobre sinal de menor) 0.2%. Steady state YN2 O-N at 25 and 30o.C (5% DOT was (1.1 (sinal de maior sobre sinal de menor)0.2%. A downshift in DOT from 0.3 to 0.2% or an an upshift in temperature from 20 to 30oC evoked a substantial transient increase in N2O production with YN2 0-N maximizing at 7.6 and 3.7%, respectively. Our results indicate that diurnal and seasonal fluctuations in temperature in the 20 to 30% rang may result in a substantial transient increase in N2O production by nitrifiers particularily in high water content soils.
Download or read book Dissertation Abstracts International written by and published by . This book was released on 2008 with total page 1006 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Communities and Ecosystems written by David A. Wardle and published by Princeton University Press. This book was released on 2002-05-12 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt: Soil.
Download or read book Denitrification and Mineralization in Agricultural Soil in Eastern Canada as Affected by Nitrogen Fertilizer Tillage and Crop Rotation written by Melissa Abbott and published by . This book was released on 1996 with total page 160 pages. Available in PDF, EPUB and Kindle. Book excerpt: "The fate of fertilizer N is of primary concern for both agricultural productivity and environmental quality. Concerns include denitrification, leaching losses, mineralization of organic N as plant available N. Denitrification is an important source of N$ sb2$O, a greenhouse gas but field measurements are difficult. Two methods of measuring denitrification are soil core (SC) incubation and closed chamber (CC) methods. These methods were assessed on soil under monoculture corn, monoculture soybean, and alfalfa in a corn soybean alfalfa rotation. Greater concentrations were found in the CC method than the SC method. Denitrification rates ranged from less than 15 g N ha$ sp{-1}$h$ sp{-1}$ to nearly 2000 g N ha$ sp{-1}$h$ sp{-1}$. The CC method was more sensitive to treatment effects. The denitrification rates were dependent on the soil type, being higher on soils with high clay content. The variables that had the highest degree of relationship with denitrification were water filled pore space, soil NH$ sb4$-N and NO$ sb3 $,-N concentrations. Higher rates of N increased denitrification. As to assessment of available soil N, this was accomplished N and C mineralization measurements. Potentially mineralizable N(N$ sb0$) ranged from 144 mg N kg$ sp{-1}$ to 30.3 mg N kg$ sp{-1}$. Higher rates of organic amendment resulted in higher measured values on Brandon soil while higher rates of inorganic N on Chicot and Ste. Rosalie soils caused no change in mineralizable N or respired C. Total N, organic C, water soluble organic C (WSOC) and microbial biomass C (MBC) increased with increasing amounts of organic or inorganic N amendment on Brandon soil. Higher rates of inorganic N resulted in lower WSOC and MBC on Chicot and Ste. Rosalie soils. Nitrogen mineralized, C respired, total N, organic C, WSOC and MBC were all related to soil texture. MBC and WSOC were found to have a strong positive relationship with potentially mineralizable N." --
Download or read book Soil Productivity Enhancement written by Roland Nuhu Issaka and published by BoD – Books on Demand. This book was released on 2018-11-28 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt: Soil Productivity Enhancement comprises five chapters written by scientists from various parts of the world. The book is divided into three sections. 1: Conversion of Environmentally Polluting Waste into Fertilizer. This section discusses the conversion of waste water and other by-products from factories into organic fertilizers. It further examines how these materials can be used to enhance crop production and improve soil productivity. 2: Practices for Improving Nutrient Availability. Good nutrient management and proper composting of organic materials are options that can be used to enhance the productivity of soil. These and other practices are examined in this section. 3: Policy on Fertilizer Use. The need for effective policies to control and promote the effective and efficient use of fertilizers is discussed in this section.
Download or read book Soil Biology written by J. L. Hatfield and published by CRC Press. This book was released on 2018-01-18 with total page 175 pages. Available in PDF, EPUB and Kindle. Book excerpt: Soil Biology is a state-of-the art review focusing on the linkage between biological processes that occur in the soil and their impact on soil quality. Topics considered include the microbial ecology of conservation management systems, dynamic processes of vesicular-arbuscular mycorrhizae, earthworms and soil fauna, microbial processes in the soil, and the degradation of pesticides through microbial processes. The book will interest soil scientists, microbiologists, agronomists, and soil ecologists.
Download or read book Soil N Mineralization Dynamics as Affected by Pure and Mixed Application of Leafy Material from Leguminous Trees Used in Planted Fallow in Brazil written by José Henrique Cattanio and published by . This book was released on 2002 with total page 125 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study showes that the quality and the quantity of organic material presented an important factor affecting soil nitrogen mineralization and immobilization. Changes in soil carbon substrates influenced the dynamics of soil inorganic nitrogen because of the importance of labile carbon in the microbial immobilization and consumption of nitrogen. Contrasting leguminous species had different patterns of net N-mineralization and -immobilization in comparison with the single species. The use of two contrasting leguminous species increasede the nitrogen absorption by rice through the increase of mineral-N in soil and a decrease of gross microbial N-immobilization. The study demonstrates that the plant and microbial system compete for N in the soil, and the data showed a mutual N limitation and the use of the same N-resource.
Download or read book Soil Health and Intensification of Agroecosystems written by Mahdi M. Al-Kaisi and published by Academic Press. This book was released on 2017-03-15 with total page 420 pages. Available in PDF, EPUB and Kindle. Book excerpt: Soil Health and Intensification of Agroecosystems examines the climate, environmental, and human effects on agroecosystems and how the existing paradigms must be revised in order to establish sustainable production. The increased demand for food and fuel exerts tremendous stress on all aspects of natural resources and the environment to satisfy an ever increasing world population, which includes the use of agriculture products for energy and other uses in addition to human and animal food. The book presents options for ecological systems that mimic the natural diversity of the ecosystem and can have significant effect as the world faces a rapidly changing and volatile climate. The book explores the introduction of sustainable agroecosystems that promote biodiversity, sustain soil health, and enhance food production as ways to help mitigate some of these adverse effects. New agroecosystems will help define a resilient system that can potentially absorb some of the extreme shifts in climate. Changing the existing cropping system paradigm to utilize natural system attributes by promoting biodiversity within production agricultural systems, such as the integration of polycultures, will also enhance ecological resiliency and will likely increase carbon sequestration. Focuses on the intensification and integration of agroecosystem and soil resiliency by presenting suggested modifications of the current cropping system paradigm Examines climate, environment, and human effects on agroecosystems Explores in depth the wide range of intercalated soil and plant interactions as they influence soil sustainability and, in particular, soil quality Presents options for ecological systems that mimic the natural diversity of the ecosystem and can have significant effect as the world faces a rapidly changing and volatile climate
Download or read book Carbon and Nitrogen Cycling in Soil written by Rahul Datta and published by Springer Nature. This book was released on 2019-08-24 with total page 498 pages. Available in PDF, EPUB and Kindle. Book excerpt: Several textbooks and edited volumes are currently available on general soil fertility but‚ to date‚ none have been dedicated to the study of “Sustainable Carbon and Nitrogen Cycling in Soil.” Yet this aspect is extremely important, considering the fact that the soil, as the ‘epidermis of the Earth’ (geodermis)‚ is a major component of the terrestrial biosphere. This book addresses virtually every aspect of C and N cycling, including: general concepts on the diversity of microorganisms and management practices for soil, the function of soil’s structure-function-ecosystem, the evolving role of C and N, cutting-edge methods used in soil microbial ecological studies, rhizosphere microflora, the role of organic matter (OM) in agricultural productivity, C and N transformation in soil, biological nitrogen fixation (BNF) and its genetics, plant-growth-promoting rhizobacteria (PGPRs), PGPRs and their role in sustainable agriculture, organic agriculture, etc. The book’s main objectives are: (1) to explain in detail the role of C and N cycling in sustaining agricultural productivity and its importance to sustainable soil management; (2) to show readers how to restore soil health with C and N; and (3) to help them understand the matching of C and N cycling rules from a climatic perspective. Given its scope, the book offers a valuable resource for educators, researchers, and policymakers, as well as undergraduate and graduate students of soil science, soil microbiology, agronomy, ecology, and the environmental sciences. Gathering cutting-edge contributions from internationally respected researchers, it offers authoritative content on a broad range of topics, which is supplemented by a wealth of data, tables, figures, and photographs. Moreover, it provides a roadmap for sustainable approaches to food and nutritional security, and to soil sustainability in agricultural systems, based on C and N cycling in soil systems.
Download or read book American Doctoral Dissertations written by and published by . This book was released on 1994 with total page 800 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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.
Download or read book Soil Organic Matter in Temperate AgroecosystemsLong Term Experiments in North America written by Eldor A. Paul and published by CRC Press. This book was released on 2019-08-16 with total page 436 pages. Available in PDF, EPUB and Kindle. Book excerpt: The presence - or absence - of soil organic matter (SOM) has important implications for agricultural productivity. It could also have significant implications for global climate due to its role as a source/sink of carbon. Therefore, it is important to understand the issues related to the accumulation or loss of SOM, to use what we have learned from experiments to make sound decisions about soil and crop management, and to test models and future concepts concerning SOM management. A database is included with the book, presenting tabular data for 34 sites in North America. Soil Organic Matter in Temperate Agroecosystems discusses all of these issues and more, answering such questions as:
Download or read book Soil Nitrogen Mineralization as Affected by Drying Liming and Sewage Sludge Addition written by Nazir Ahmad and published by . This book was released on 1980 with total page 294 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The California Nitrogen Assessment written by Thomas P. Tomich and published by Univ of California Press. This book was released on 2016-06-14 with total page 341 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nitrogen is indispensable to all life on Earth. However, humans now dominate the nitrogen cycle, and nitrogen emissions from human activity have real costs: water and air pollution, climate change, and detrimental effects on human health, biodiversity, and natural habitats. Too little nitrogen limits ecosystem processes, while too much nitrogen transforms ecosystems profoundly. The California Nitrogen Assessment is the first comprehensive account of nitrogen flows, practices, and policies for California, encompassing all nitrogen flows—not just those associated with agriculture—and their impacts on ecosystem services and human wellbeing. How California handles nitrogen issues will be of interest nationally and internationally, and the goal of the assessment is to link science with action and to produce information that affects both future policy and solutions for addressing nitrogen pollution. This book also provides a model for application of integrated ecosystem assessment methods at regional and state (subnational) levels.
Download or read book Managing Nutrient Cycles to Sustain Soil Fertility in Sub Saharan Africa written by André Bationo and published by CIAT. This book was released on 2004 with total page 632 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Advances in Agronomy written by and published by Elsevier. This book was released on 2000-01-10 with total page 347 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advances in Agronomy continues to be recognized as a leading reference and a first-rate source of the latest and best research in agronomy. As always, the topics covered are varied and exemplary of the panoply of subject matter dealt with by this long-running serial.Volume 68 contains five outstanding and contemporary reviews on topics that deal with soil chemistry, plant physiology, plant nutrition, and soil and crop management. Chapter 1 by Morris Schnitzer summarizes the past and present knowledge of the chemistry of soil organic matter. Chapter 2, written by H.S. Saini and M.E. Westgate, is a comprehensive exposition on the reproductive development in grain crops during drought. G. Xu, H. Magen, J. Tarchitzky, and U. Kafkafi present advances in chloride management in Chapter 3. Chapter 4 is a review in our continuing series on the 12 soil orders. S.W. Buol and H. Eswaran provide an enlightening review on Oxisols. K. Kumar and K.M. Goh discuss aspects of crop residues in the fifth and final chapter of this important and well-written book.
