Soil Nitrogen


Book Description

Origin and distribution of nitrogen in soil. Soil inorganic nitrogen. Organic nitrogen in soils. Ammonium fixation and other reactions involving a nonenzymatic immobilization of mineral nitrogen in soil. Mineralization and immobilization of nitrogen in the decomposition of plant and animal residues. Nitrification. Denitrification. Symbiotic nitrogen fixation. Environmental factors in the fixation of nitrogen by the legume. Nonsymbiotic nitrogen fixation. The plant's need for and use of nitrogen. Movement of nitrogen in soil. Evaluation of incoming and outgoing processes thar affect soil nitrogen.




Agriculture and the Nitrogen Cycle


Book Description

Nitrogen is an essential element for plant growth and development and a key agricultural input-but in excess it can lead to a host of problems for human and ecological health. Across the globe, distribution of fertilizer nitrogen is very uneven, with some areas subject to nitrogen pollution and others suffering from reduced soil fertility, diminished crop production, and other consequences of inadequate supply. Agriculture and the Nitrogen Cycle provides a global assessment of the role of nitrogen fertilizer in the nitrogen cycle. The focus of the book is regional, emphasizing the need to maintain food and fiber production while minimizing environmental impacts where fertilizer is abundant, and the need to enhance fertilizer utilization in systems where nitrogen is limited. The book is derived from a workshop held by the Scientific Committee on Problems of the Environment (SCOPE) in Kampala, Uganda, that brought together the world's leading scientists to examine and discuss the nitrogen cycle and related problems. It contains an overview chapter that summarizes the group's findings, four chapters on cross-cutting issues, and thirteen background chapters. The book offers a unique synthesis and provides an up-to-date, broad perspective on the issues of nitrogen fertilizer in food production and the interaction of nitrogen and the environment.




Nitrogen in the Environment: Sources, Problems and Management


Book Description

Nitrogen in the Environment: Sources, Problems, and Management is the first volume to provide a holistic perspective and comprehensive treatment of nitrogen from field, to ecosystem, to treatment of urban and rural drinking water supplies, while also including a historical overview, human health impacts and policy considerations. It provides a worldwide perspective on nitrogen and agriculture. Nitrogen is one of the most critical elements required in agricultural systems for the production of crops for feed, food and fiber. The ever-increasing world population requires increasing use of nitrogen in agriculture to supply human needs for dietary protein. Worldwide demand for nitrogen will increase as a direct response to increasing population. Strategies and perspectives are considered to improve nitrogen-use efficiency. Issues of nitrogen in crop and human nutrition, and transport and transformations along the continuum from farm field to ground water, watersheds, streams, rivers, and coastal marine environments are discussed. Described are aerial transport of nitrogen from livestock and agricultural systems and the potential for deposition and impacts. The current status of nitrogen in the environment in selected terrestrial and coastal environments and crop and forest ecosystems and development of emerging technologies to minimize nitrogen impacts on the environment are addressed. The nitrogen cycle provides a framework for assessing broad scale or even global strategies to improve nitrogen use efficiency. Growing human populations are the driving force that requires increased nitrogen inputs. These increasing inputs into the food-production system directly result in increased livestock and human-excretory nitrogen contribution into the environment. The scope of this book is diverse, covering a range of topics and issues from furthering our understanding of nitrogen in the environment to policy considerations at both farm and national scales.




Soil–Plant–Nitrogen Relationships


Book Description

Nitrogen in the Environment, Volume 2: Soil-Plant-Nitrogen Relationships is the second of a two-volume treatise based on manuscripts presented at the international conference on ""Nitrogen in the Environment,"" held at the University of California Conference Center, Lake Arrowhead, in February, 1977. All original manuscripts were revised in accordance with discussions at the conference. The chapters published in these volumes are those revised manuscripts, with provisions in each chapter to preserve the major suggestions for their improvement. These two volumes—Nitrogen Behavior in Field Soil and Soil-Plant-Nitrogen Relationships—should be of value in bringing into perspective current knowledge on selected aspects of nitrogen in the environment. The book contains 22 chapters and opens with a study on the factors influencing nitrate acquisition by plants; assimilation and fate of reduced nitrogen. Separate chapters follow on topics such as absorption and utilization of ammonium nitrogen by plants; potential nitrate levels in edible plant parts; control of biological nitrogen fixation; and methods for analysis of denitrification in soils.




Properties and Management of Soils in the Tropics


Book Description

Long-awaited second edition of classic textbook, brought completely up to date, for courses on tropical soils, and reference for scientists and professionals.




The European Nitrogen Assessment


Book Description

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.




Symbiotic Nitrogen Fixation


Book Description

During the past three decades there has been a large amount of research on biological nitrogen fixation, in part stimulated by increasing world prices of nitrogen-containing fertilizers and environmental concerns. In the last several years, research on plant--microbe interactions, and symbiotic and asymbiotic nitrogen fixation has become truly interdisciplinary in nature, stimulated to some degree by the use of modern genetic techniques. These methodologies have allowed us to make detailed analyses of plant and bacterial genes involved in symbiotic processes and to follow the growth and persistence of the root-nodule bacteria and free-living nitrogen-fixing bacteria in soils. Through the efforts of a large number of researchers we now have a better understanding of the ecology of rhizobia, environmental parameters affecting the infection and nodulation process, the nature of specificity, the biochemistry of host plants and microsymbionts, and chemical signalling between symbiotic partners. This volume gives a summary of current research efforts and knowledge in the field of biological nitrogen fixation. Since the research field is diverse in nature, this book presents a collection of papers in the major research area of physiology and metabolism, genetics, evolution, taxonomy, ecology, and international programs.




Genetic Aspects of Plant Nutrition


Book Description

The idea of addressing the problem of the genetic specificity of mineral nutrition at an international level arose four years ago in a proposal for this topic to be included in the program of the II Congress of the Federation of European Societies for Plant Physiology (FESPP) as a separate section. The Organising Committee of the II Congress of FESPP which was held in Santiago de Compostella in 1980 arranged a special session and it was clearly successful. A special scientific meeting where the genetic aspects of plant nutrition in their widest sense could be presented and discussed comprehensively appeared to be necessary and that is how this Symposium came to be organized by the Serbian Academy of Sciences and Arts. Much progress has already been achieved in this field, and bearing in mind the importance of this problem, particularly at the present moment, it is necessary for us both to acquaint ourselves with what has been achieved so far, and even more to direct attention and effort to the fundamental problems for the future.




Know Soil, Know Life


Book Description

Audience: Students studying environmental science or participating in an Envirothon or Science Olympiad will find Know Soil, Know Life is an easily accessible resource. Undergraduate students in introductory ecology and environmental science classes will have a manageable soils textbook. Scientists in related disciplines wildlife, forestry, geology, hydrology, biology, zoology will enjoy this engaging introduction to soils.