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.







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.







A Molecular Approach To Primary Metabolism In Higher Plants


Book Description

Discusses and explains the major advances that the new technology of applying molecular genetic techniques of modifying carbon and nitrogen in plants has provided, giving insights into its applications for the benefits of agriculture, the environment and man. The text is divided into three sections, the first focusing on primary nitrogen and carbon







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.




Plant Developmental Biology - Biotechnological Perspectives


Book Description

Many exciting discoveries in recent decades have contributed new knowledge to our understanding of the mechanisms that regulate various stages of plant growth and development. Such information, coupled with advances in cell and molecular biology, is fundamental to crop improvement using biotechnological approaches. Two volumes constitute the present work. The ?rst, comprising 22 chapters, commences with introductions relating to gene regulatory models for plant dev- opment and crop improvement, particularly the use of Arabidopsis as a model plant. These chapters are followed by speci?c topics that focus on different developmental aspects associated with vegetative and reproductive phases of the life cycle of a plant. Six chapters discuss vegetative growth and development. Their contents consider topics such as shoot branching, bud dormancy and growth, the devel- ment of roots, nodules and tubers, and senescence. The reproductive phase of plant development is in 14 chapters that present topics such as ?oral organ init- tion and the regulation of ?owering, the development of male and female gametes, pollen germination and tube growth, fertilization, fruit development and ripening, seed development, dormancy, germination, and apomixis. Male sterility and self-incompatibility are also discussed.