Nitrogen Turnover in the Soil-Crop System


Book Description

In the Netherlands the Institute for Soil Fertility Research plays a major role in soil biological, soil physical and plant nutritional research on the availability of nitrogen to crops. Main subjects of research are nitrogen turnover in the crop-soil ecosystem through biological transformations, nitrogen transport through the soil and nitrogen losses by leaching, denitrification and volatilization, and nitrogen use efficiency of various crops and cropping systems. The current knowledge in the different fields of research is integrated in simulation models. Simulation models not only make it possible to summarize and structure knowledge, but also, after verification, to extra- late the knowledge to situations different from the situations that have actually been studied. Such research is also carried out in other European and non-European countries. To compare the various simulation models currently in use, a workshop was organized by the Institute for Soil Fertility Research on 5-6 June 1990 on the occasion of its centennial. The title of the workshop was 'Nitrogen turnover in the soil-crop ::cosystem: modelling of biological transformations, transport of nitrogen and nitrogen use efficiency'. The 40 Jarticipants, who came from Canada and various European countries, were requested to run their model with data Jrovided by the Institute prior to the workshop. Data from 18 cases were made available to the participants: three ocations, three treatments, and two seasons.










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.




Nitrogen in Agricultural Soils


Book Description

Origem and distribution of nitrogen in soil. Inorganic forms of nitrogen in soil. Organic forms of soil nitrogen. Retention and fixation of ammonium and ammonim in soils. Biochemistry ammonification. Mineralization and Immobilization of soil nitrogem. Nitrogen trasport processes in soil. Nitrogen transformations in submerged soil. Advances in methodology for research on nitrogen transformations. Soil nitrogen budgets. Crop nitrogen requirements, utilizations, and fertilization. Nitrogen management for maximum efficiency and minimum pollution. Assesment of soil nitrogen availability. The effect of pesticides on nitrogen transformation in soils. Modeling of the soil nitrogen cycle. Economic implications of controls on nitrogen fertilizer use. Recycling of nitrogen through land application of agricultural, food processing, and municipal wastes. Energetics of nitrogen transformations. Nitrogem transfers and mass balances.




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.