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This accessible textbook takes a broad approach to river ecology, covering the basics but going beyond by including topics that are often overlooked such as blackwater streams and rivers, tidal creek ecosystems, and reservoir limnology. There is significant emphasis on anthropogenic impacts.

Basing on analysis of size and age structure and observation during 9 years within the two permanent plots in Arkhangelsk Region (Pinega district), dynamics of spruce (Picea obovata Ledeb.) and birch (Betula pubescens Ehrh.) populations was described in old-growth spruce forests. Because of rare tree layer, light regime in both communities is favorable: it enhances tolerance of spruce plants to strong soil moisture and reduces mortality in populations. But a lack of drained surfaces restricts recruitment of these populations.

Our species has transitioned from being one among millions on Earth to the species that is single-handedly transforming the entire planet to suit its own needs. In order to meet the daunting challenges of environmental sustainability in this epoch of human domination - known as the Anthropocene - ecologists have begun to think differently about the interdependencies between humans and the natural world. This work provides the best available introduction to what this new ecology is all about - and why it matters more than ever before

This important contribution is the result of decades of theoretical thinking and high-value data collection by the University of Helsinki examining forest ecosystems in great detail. The ecology is dominated by a qualitative approach, e.g. species and vegetation zones, but in contrast quantitative thinking is characteristic in the exact sciences of physics and physiology. The editors have bridged the gap between ecology and the exact sciences with an interdisciplinary and quantitative approach. This book recognizes this discrepancy as a hindrance to fruitful knowledge flow between the disciplines, and that physical and physiological knowledge has been omitted from forest ecology to a great extent. Starting with the importance of mass and energy flows in the interactions between forest ecosystems and their environment, the editors and authors offer a strong contribution to the pioneer H. T. Odum and his work from over 50 years ago.This book introduces a holistic synthesis of carbon and nitrogen fluxes in forest ecosystems from cell to stand level during the lifetime of trees. Metabolism and physical phenomena give rise to concentration, pressure and temperature differences that generate the material and energy fluxes between living organisms and their environment. The editors and authors utilize physiological, physical and anatomical background information to formulate theoretical ideas dealing with the effects of the environment and the state of enzymes, membrane pumps and pigments on metabolism. The emergent properties play an important role in the transitions from detailed to more aggregate levels in the ecosystem. Conservation of mass and energy allow the construction of dynamic models of carbon and nitrogen fluxes and pools at various levels in the hierarchy of forest ecosystems.Testing the predictions of these theories dealing with different phenomena in forest ecosystems was completed using the versatile and extensive data measured at SMEAR I and II (Stations for Measuring Ecosystem Atmosphere Relations) and at six additional stands in Finland, and five stands in Estonia. The theories are able to predict fluxes at different levels in the forest ecosystem gaining strong corroboration in the numerous field tests. Finally, the combined results from different hierarchical levels in the forest ecosystem form the physical and physiological theory of forest ecology.

Challenges the view that the lowlands of Central and Western Europe would revert to their prehistoric state of closed forest systems if free from human intervention. This text uses examples from pollen analyses and studies on tree species, and tests hypothesis of herbivore governance of vegetation.

Historically, tropical ecology has been a science often content with descriptive and demographic approaches, which is understandable given the difficulty of studying these ecosystems and the need for basic demographic information. Nonetheless, over the last several years, tropical ecologists have begun to test more sophisticated ecological theory and are now beginning to address a broad array of questions that are of particular importance to tropical systems, and ecology in general. Why are there are so many species in tropical forests and what mechanisms are responsible for the maintenance of that vast species diversity? What factors control species coexistence? Are there common patterns of species abundance and distribution across broad geographic scales? What is the role of trophic interactions in these complex ecosystems? How can these fragile ecosystems be conserved? Tropical Forest Community Ecology includes contributions from some of the world's leading tropical ecologists who address these key issues and many others, providing a unique and timely summary of this discipline.

Ilus. Tab. Bib. Sum. (En) ; Secondary forests developing on agricultural land after it is abandoned, or as the fallow period in systems of subsistence agriculture, are an increasingly important component of the forest resources of the tropics. They fix and store carbon and may contribute to the alleviation of global warming, they are refuges for biodiversity in agricultural landscapes, and they are low-cost sources of a tremendous variety of forest products. The final years of the 20th century represent an opportune time to bring together researchers concerned with biological, ecological, social/organizational, financial/economic and political aspects of secondary forests and their management, to share their experiences and opinions concerning secondary tropical forests and to contribute to the development of a forward-looking, cross-disciplinary research agenda. The conference had the following objectives: 1) to summarize the state of knowledge of tropical secondary forests from the standpoint of the ecological, social and political sciences. 2) to report the most recent results of research on secondary forests from all relevant disciplines.

▪ Abstract  This review asks the question: What new avenues of social science enquiry are suggested by new ecological thinking, with its focus on nonequilibrium dynamics, spatial and temporal variation, complexity, and uncertainty? Following a review of the emergence of the "new ecology" and the highlighting of contrasts with earlier "balance of nature" perspectives, work emerging from ecological anthropology, political ecology, environmental and ecological economics, and debates about nature and culture are examined. With some important exceptions, much social science work and associated popular and policy debates remain firmly wedded to a static and equilibrial view. This review turns to three areas where a more dynamic perspective has emerged. Each has the potential to take central elements of new ecological thinking seriously, sometimes with major practical consequences for planning, intervention design, and management. First is the concern with spatial and temporal dynamics developed in detailed and situated analyses of "people in places," using, in particular, historical analysis as a way of explaining environmental change across time and space. Second is the growing understanding of environment as both the product of and the setting for human interactions, which link dynamic structural analyses of environmental processes with an appreciation of human agency in environmental transformation, as part of a "structuration" approach. Third is the appreciation of complexity and uncertainty in social-ecological systems and, with this, the recognition of that prediction, management, and control are unlikely, if not impossible.