Xem 1-20 trên 55 kết quả Forest ecology
  • Research in tropical forestry is confronted with the task of finding strategies to alleviate pressure on remaining forests, and techniques to enhance forest regeneration and restore abandoned lands, using productive alternatives that can be attractive to local human populations. In addition, sustainable forestry in tropical countries must be supported by adequate policies to promote and maintain specific activities at local and regional scales.

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  • Forests play a major role in global carbon (C) cycle, and the carbon density (CD) could reflect its ecological function of C sequestration. Study on the CD of different forest types on a community scale is crucial to characterize in depth the capacity of forest C sequestration.

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  • Whereas the mechanical performance of plant organs has often been discussed in evolutionary biology [1,2], tree biomechanics has rarely been considered in the context of functional ecology. Functional ecology aims at understanding the functions of organisms that result in fluxes of biomass or energy within an ecosystem, e.g., a forest. This discipline studies the processes controlling these fluxes, at either the scale of an individual, community, or ecosystem, with their response to natural or anthropic environmental variations....

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  • The concept of forest sustainability dates from centuries ago, although the understanding of sustainable forest management (SFM) as an instrument that harmonizes ecological and socio-economic concerns is relatively new. The change in perspective occurred at the beginning of the 1990s in response to an increased awareness of the deterioration of the environment, in particular of the alarming loss of forest resources. The main and most striking cause of this deterioration is the deforestation occurring in some areas of the world.

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  • Few things in the universe are constant over thousands or millions of years, not the orbit of the Earth around the sun, the height of eroding mountains, the distribution of boreal forests, or the abundance of a particular species. As we shift our attention from the stellar and global to the regional and local, then the more likely it is that we will encounter things that change over even short spans of time.

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  • The rain forest takes an immense breath and then exhales, once every four or five years, as a major global weather pattern plays out, usually heralded by El Nin˜o–Southern Oscillation. While this powerful natural cycle has occurred for many millennia, it is during the past decade that both the climate of Earth and the people living on it have had an increasing influence on the weather pattern itself, with many biological consequences. In Southeast Asia, as also in most of the Neotropics, El Nin˜o accompanies one of the most exuberant outpourings of nature’s diversity.

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  • Human activities are affecting the global environment in myriad ways, with numerous direct and indirect effects on ecosystems. The climate and atmospheric composition of Earth are changing rapidly. Humans have directly modified half of the ice-free terrestrial surface and use 40% of terrestrial production. Our actions are causing the sixth major extinction event in the history of life on Earth and are radically modifying the interactions among forests, fields, streams, and oceans.

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  • The history and development of the longleaf pine (Pinus palustris Mill.) ecosystem in the southeastern United States has intrigued natural resource professionals, researchers, and the general public for many decades. Prior to European settlement, longleaf pine forests were one of the most extensive ecosystems in North America. Most recent estimates suggest that only about 2.2% of the original area remains today, making it one of the most threatened ecosystems in North America.

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  • This book, now in its third edition, began almost 25 years ago when Weed Ecology: Implications for Vegetation Management was published in 1984. That text concentrated on the need for farmers, foresters, rangeland managers, and the researchers who advised them to understand better the biology of weeds and the role people play in creating and maintaining weeds in agriculture and other production systems. We were assisted in that first effort by the writings of many early scientists, such as J. L. Harper, H. G. Baker, and E. J.

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  • In 1950, the United States Department of Energy (then the U.S. Atomic Energy Commission) began purchasing the land that became the present Savannah River Site (SRS). All residents were removed (figure A), and in 1951 the government closed the site to the public to begin work on production of nuclear weapons materials. At the time, abandoned agricultural fields dominated upland areas, and the SRS and the USDA Forest Service initiated an aggressive reforestation program.

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  • Environmentalists are often regarded as people wanting to stop one thing or another, and there are surely lots of things that ought to be stopped. The essays in this book, however, have to do with beginnings. How, for example, do we advance a long-delayed solar revolution? Or begin one in forest management? Or materials use? How do we reimagine and remake the human presence on earth in ways that work over the long haul? Such questions are the heart of what theologian Thomas Berry (1999) calls “the Great Work” of our age....

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  • Environmentalists are often regarded as people wanting to stop one thing or another, and there are surely lots of things that ought to be stopped. The essays in this book, however, have to do with beginnings. How, for example, do we advance a long-delayed solar revolution? Or begin one in forest management? Or materials use? How do we reimagine and remake the human presence on earth in ways that work over the long haul? Such questions are the heart of what theologian Thomas Berry (1999) calls “the Great Work” of our age....

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  • John H. Vandermeer Ph.D., is a Margaret Davis Collegiate Professor in the Department of Ecology and Evolutionary Biology at the University of Michigan, Ann Arbor. His work has been in tropical agroecosystem ecology, tropical forest ecology, and theoretical ecology. He is the author of over 150 scientific articles and 9 books. Professor Vandermeer was born in 1940 in Chicago, Illinois. He received his BS in zoology from the University of Illinois, Champaign/Urbana, and his masters in zoology from the University of Kansas.

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  • Soil fertility describes soil nutrient status and the factors controlling the supply of nutrients to plants. Continued efforts to improve soil fertility are required to support the world's growing demand for food, fiber, and renewable fuels. Important ecological services provided by soils, such as biodiversity, buffering capacity, and nutrient recycling benefit from the amendments applied to sustain soil fertility. Those amendments need to be applied in a manner that is both economical and practical for the producer to achieve agronomic objectives that are environmentally sound.

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  • This book provides an interdisciplinary view of how to prepare the ecological and socio-economic systems to the reality of climate change. Scientifically sound tools are needed to predict its effects on regional, rather than global, scales, as it is the level at which socio-economic plans are designed and natural ecosystem reacts. The first section of this book describes a series of methods and models to downscale the global predictions of climate change, estimate its effects on biophysical systems and monitor the changes as they occur....

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  • Creating institutions to meet the challenge of sustainability is arguably the most important task confronting society; it is also dauntingly complex. Ecological, economic, and social elements all play a role, but despite ongoing efforts, researchers have yet to succeed in integrating the various disciplines in a way that gives adequate representation to the insights of each.Panarchy, a term devised to describe evolving hierarchical systems with multiple interrelated elements, offers an important new framework for understanding and resolving this dilemma.

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  • This book contains most of the papers presented at the Eco-Architecture 2010 conference, which was the third edition of the International Conference on Harmonisation between Architecture and Nature. Previous editions were held in the New Forest, UK (2006) and the Algarve, Portugal (2008) and demonstrated the importance of a forum like this to discuss the characteristics and challenges of such architectural vision. Eco-Architecture implies a new approach to the design process intended to harmonise its products with nature.

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  • Else_SP-Jorgensen_prelims.qxd 4/11/2007 18:24 Page i A New Ecology: Systems Perspective Else_SP-Jorgensen_prelims.qxd 4/11/2007 18:24 Page ii Front cover photo is by B.D. Fath and shows Møns Klint, Denmark. The back cover photos show (from left to right) (1) a danish beech forest (Ryget Skov), (2) Krimml Falls in Austria, (3) part of the shore of Namchu Lake in Tibet, (4) Crater Lake, Oregan, USA, and (5) Natron Lake, Tanzania and were taken by S.E. Jørgensen (1 and 4), B.D. Fath (2), and M.V. Jørgensen (3 and 5). Else_SP-Jorgensen_prelims.

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  • Since the 1930s, the USDA (U.S. Department of Agriculture) Forest Service’s International Institute of Tropical Forestry (the Institute) has studied mahogany and its management. In the 1960s, F.B. Lamb, the author of the classic book on mahogany (1966), was an Institute collaborator. Before gene flow and genetic erosion became popular terms, my predecessor Frank Wadsworth established a gene bank at the Luquillo Experimental Forest.

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  • Sewage sludge as an uncalled for product of wastewater treatment poses the challenge to society of disposing of it, but at the same time gives us the opportunity of beneficial use by closing the cycle of nutrients: sludge derived from agricultural activity must return to soil if a sustainable and ecologically sound management of these materials is desirable (SEQUI et al. 2000). At present the major ways of disposing of sewage sludges are deposition, landfill and incineration, only part of the sludges are used in agriculture. ...

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