الصفحة 1
الصفحة 1
Nutrient Cycling in Terrestrial Ecosystems
The first part of the book presents the fundamentals of nutrient cycling. Topics included are cycling of carbon, nitrogen, phosphorus, sulphur and micronutrients. The second part discusses nutrient cycling at an ecosystem scale, covering cropping systems, pastures, natural grasslands, arid lands, tundras and forests. The final chapter reviews current models of nutrient cycling.
Nitrogen Fixation in Agriculture, Forestry, Ecology, and the Environment
Sustainability has a major part to play in the global challenge of continued development of regions, countries, and continents all around the World and biological nitrogen fixation has a key role in this process. This volume begins with chapters specifically addressing crops of major global importance, such as soybeans, rice, and sugar cane. It continues with a second important focus, agroforestry, and describes the use and promise of both legume trees with their rhizobial symbionts and other nitrogen-fixing trees with their actinorhizal colonization. An over-arching theme of all chapters is the interaction of the plants and trees with microbes and this theme allows other aspects of soil microbiology, such as interactions with arbuscular mycorrhizal fungi and the impact of soil-stress factors on biological nitrogen fixation, to be addressed. Furthermore, a link to basic science occurs through the inclusion of chapters describing the biogeochemically important nitrogen cycle and its key relationships among nitrogen fixation, nitrification, and denitrification. The volume then provides an up-to-date view of the production of microbial inocula, especially those for legume crops.
Nitrogen Cycling in the Americas : Natural and Anthropogenic Influences and Controls
The rate of creation of reactive nitrogen (NR) on the earth has dramatically increased in the last half century mainly due to the production of N-fertilizer through the Haber-Bosch process, fossil fuel combustion, and the cultivation of plants that fix N from the atmosphere. The anthropogenic production of NR has been especially high in developed countries of the temperate zone, such as the USA and Canada, where severe eutrophication of estuaries and coastal zones, acidification of lakes and streams, loss of biodiversity, and reduced forest productivity have become common environmental problems associated with increasing nitrogen loads to ecosystems. This book presents a series of studies from across the Americas whose aim is to highlight key natural processes that control nitrogen cycling as well as discuss the main anthropogenic influences on the nitrogen cycle in both the tropical and temperate regions of the Americas.
Microorganisms in soils : Roles in genesis and functions
The following key topics are covered: Microorganisms in bioerosion, humification, mineralization and soil aggregation; Microbial energetics and microbes in biogeochemical processes such as carbon and nitrogen cycles and phosphorus bio-availability; Interactions in the mycorrhizosphere, e.g. between mycorrhizal fungi and bacteria; Impact of microbes on plant nutrient cycling and the possible effects of transgenic rhizospheres on soil fungi; Functions of microbes in specific soil compartments such as soil surface or toxic metal polluted soils; Regulation of microbial activities in functional domains that are influenced by biotic or abiotic factors; Use of marker genes and isotopes as examples for modern techniques in soil microbiology.
