Inorganic Nitrogen in Plants and Microorganisms


Book Description

Inorganic Nitrogen in Plants and Microorganisms summarizes new experimental data, ideas and conclusions on the whole metabolic spectrum: - transport through the cell membranes, - the distribution within plant organs, - nitrate and nitrite reduction with their complicated genetic and physiological regulation, - the assimilation of ammonium and dinitrogen. Short reviews cover the dissimilatory reduction of the various inorganic nitrogen intermediates by bacteria, genetic regulation, and ecological and environmental problems. Inorganic Nitrogen in Plants and Microorganisms will help readers understand recent developments in the field of inorganic nitrogen uptake and metabolism.







Biology of Inorganic Nitrogen and Sulfur


Book Description

Nitrogen and sulfur compounds are continuously synthetized, degraded and converted into other forms in nature. There are many similarities in the principle problems and basic mechanisms of the biology of inorganic nitrogen and sulfur. Many details are not yet understood and hence are the subject of active investigation the world over. In May, 1980, a conference was held in Bochum, Federal Republic of Germany, at which attempts were made to discuss and compare all aspects of both the nitrogen and the sulfur cycle. Lectures were given by internationally recognized experts on the physiology, biochemistry, genetics, and ecology of dinitrogen fIXation, of assimilatory and dissimilatory nitrate and sulfate reduction, and of ammonia and sulfide oxidation. In addition, important data were communicated by German scientists of the national program on the Metabolism of Inorganic Nitrogen and Sulfur Compounds, supported by the Deutsche Forschungsgemeinschaft. This book contains all the contributions to the meeting and consequently should be of interest to researchers, teachers, and students in the field. The members of the German national program on the Metabolism of Inorganic Nitrogen and Sulfur Compounds would like to thank the Deutsche F orschungsgemeinschaft for their generous fmancial support of the scientific projects during the past four years and for the conference itself. Without this help, the present book would not have been written. The members express their appreciation particularly to Dr. A. Hoffmann of the Deutsche Forschungsgemeinschaft for her invaluable skill and patience in taking care of the projects and scientists.




Plants and Nitrogen


Book Description

This book discusses the association that exists between plants and their most important dietary component, nitrogen. The author combines ecological, physiological and biochemical approaches to provide the reader with an overall view of nitrogen in the biosphere and a specific view of nitrogen processing in plants. The processes which make up the nitrogen cycle, including mineralization, immobilization by microbes and nitrification, are discussed and the losses and gains of combined nitrogen from and to the cycle. The part which plants play in this cycling, by their processing of inorganic nitrogen into compounds which are required by plants and animals alike, and the chemistry and production of those compounds, is also covered. Transport of nitrogen compounds within the plant, and the fate of these compounds, is discussed. The final chapter considers the part which humans play in the cycling of nitrogen, with special reference to the nitrogen fertilizers used in agriculture.




Methods of Soil Analysis, Part 2


Book Description

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.







The Allocation of Inorganic Nitrogen (↑1↑5NH↓4[superscript]+) to Soil, Microbial and Plant Biomass in an Arctic Salt Marsh [microform]


Book Description

This study has demonstrated, through the shared distribution of a single resource (15NH4+), that plants and soil microbes compete for inorganic N in a N-limited system. At La Perouse Bay, soil microorganisms out-compete plants for this resource, but their competitive advantage is dampened relative to microorganisms in other Arctic ecosystems by the effects of goose grazing that promote plant growth via the addition of faeces. There is a seasonal displacement of N allocation, as microbes continue to mineralize and slowly immobilize nitrogen in the winter. Loss of vegetation, as a result of goose grubbing, has led to changes in soil characteristics, including high salinity and low redox potentials. These edaphic conditions may dampen N-uptake by soil microorganisms in these disturbed soils. Seasonal and grazing effects interact to contribute to a large potential N loss from these soils, although this is minimized by the apparent abiotic fixation of inorganic N.