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Resources of the Southern Fields and Forests, Medical, Economical, and Agricultural -- Being Also a Medical Botany of the Confederate States

Forgotten Books Francis Peyre Porcher

ISBN：9781333214333，出版年：2016，中图分类号：F3

The following paper is prepared by direction of the Surgeon General, for which purpose the author was released tempora rily from service in the field and hospital. It is intended as a repertory of scientific and popular knowl edge as regards the medicinal, economical, and useful properties Of the trees, plants, and shrubs found within the limits of the Confederate States, whether employed in the arts, for manufac turing purposes, or in domestic economy, to supply a present 'as well as a future want. Treating specially of our medicinal plants and of the best substitutes for foreign articles of vegeta ble origin, my aim has been to spare no exertions, compatible with the limits assigned me, to make it applicable as well to the requirements Of the Surgeon as of the Planter and Farmer; and I trust that after the war shall have ceased there will still be no diminution in the desire of every one to possess a source from whence his curiosity may be satisfied on matters pertaining to our useful plants. The Regimental Surgeon in the field, the Physician in his private practice, or the Planter on his estate may themselves collect and apply these substances within their reach, which are frequently quite as valuable as others obtained from abroad, and either impossible to be pro cured or scarce and costly. But information scattered through a variety Of sources must needs be first collected to be available in any practical point of view. I have, therefore, inserted whatever I thought would throw light upon the vegetable productions of the Confederate States,iv preface.

Agricultural economics Natural resource economics Pharmaco economics Forest pathology Economic sector Economic geography Supply-side economics Secondary sector of the economy Agriculture Economic substance

Elephants and Savanna Woodland Ecosystems -- A Study from Chobe National Park, Botswana

大象和稀树草原林地生态系统

Wiley Christina Skarpe Johan T du Toit

ISBN：9781118858615，出版年：2014，中图分类号：N

During the nineteenth century, ivory hunting caused a substantial decrease of elephant numbers in southern Africa. Soon after that, populations of many other large and medium-sized herbivores went into steep decline due to the rinderpest pandemic in the 1890s. These two events provided an opportunity for woodland establishment in areas previously intensively utilized by elephants and other herbivores. The return of elephants to currently protected areas of their former range has greatly influenced vegetation locally and the resulting potential negative effects on biodiversity are causing concern among stakeholders, managers, and scientists. This book focuses on the ecological effects of the increasing elephant population in northern Botswana, presenting the importance of the elephants for the heterogeneity of the system, and showing that elephant ecology involves much wider spatiotemporal scales than was previously thought. Drawing on the results of their research, the authors discuss elephant-caused effects on vegetation in nutrient-rich and nutrient-poor savannas, and the potential competition between elephants on the one hand and browsers and mixed feeders on the other. Ultimately this text provides a comprehensive review of ecological processes in African savannas, covering long-term ecosystem changes and human-wildlife conflicts. It summarises new knowledge on the ecology of the sub-humid African savanna ecosystems to advance the general functional understanding of savanna ecosystems across moisture and nutrient gradients.

Boreal ecosystem Mangrove ecosystem Elephantorrhiza elephantina Forest pathology Woodland caribou Southern elephant seal Grassland ecosystem Elephant seal Amazon rain forest Arid ecosystems