Community Food Webs

Community Food Webs PDF Author: Joel E. Cohen
Publisher: Springer Science & Business Media
ISBN: 3642837840
Category : Medical
Languages : en
Pages : 318

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Book Description
Food webs hold a central place in ecology. They describe which organisms feed on which others in natural habitats. This book describes recently discovered empirical regularities in real food webs: it proposes a novel theory unifying many of these regularities, as well as extensive empirical data. After a general introduction, reviewing the empirical and theoretical discoveries about food webs, the second portion of the book shows that community food webs obey several striking phenomenological regularities. Some of these unify, regardless of habitat. Others differentiate, showing that habitat significantly influences structure. The third portion of the book presents a theoretical analysis of some of the unifying empirical regularities. The fourth portion of the book presents 113 community food webs. Collected from scattered sources and carefully edited, they are the empirical basis for the results in the volume. The largest available set of data on community food webs provides a valuable foundation for future studies of community food webs. The book is intended for graduate students, teachers and researchers primarily in ecology. The theoretical portions of the book provide materials useful to teachers of applied combinatorics, in particular, random graphs. Researchers in random graphs will find here unsolved mathematical problems.

Building Community Food Webs

Building Community Food Webs PDF Author: Ken Meter
Publisher: Island Press
ISBN: 1642831476
Category : Social Science
Languages : en
Pages : 306

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Book Description
Our current food system has decimated rural communities and confined the choices of urban consumers. Even while America continues to ramp up farm production to astounding levels, net farm income is now lower than at the onset of the Great Depression, and one out of every eight Americans faces hunger. But a healthier and more equitable food system is possible. In Building Community Food Webs, Ken Meter shows how grassroots food and farming leaders across the U.S. are tackling these challenges by constructing civic networks. Overturning extractive economic structures, these inspired leaders are engaging low-income residents, farmers, and local organizations in their quest to build stronger communities. Community food webs strive to build health, wealth, capacity, and connection. Their essential element is building greater respect and mutual trust, so community members can more effectively empower themselves and address local challenges. Farmers and researchers may convene to improve farming practices collaboratively. Health clinics help clients grow food for themselves and attain better health. Food banks engage their customers to challenge the root causes of poverty. Municipalities invest large sums to protect farmland from development. Developers forge links among local businesses to strengthen economic trade. Leaders in communities marginalized by our current food system are charting a new path forward. Building Community Food Webs captures the essence of these efforts, underway in diverse places including Montana, Hawai‘i, Vermont, Arizona, Colorado, Indiana, and Minnesota. Addressing challenges as well as opportunities, Meter offers pragmatic insights for community food leaders and other grassroots activists alike.

Community Food Webs

Community Food Webs PDF Author: Joel E. Cohen
Publisher: Springer Science & Business Media
ISBN: 3642837840
Category : Medical
Languages : en
Pages : 318

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Book Description
Food webs hold a central place in ecology. They describe which organisms feed on which others in natural habitats. This book describes recently discovered empirical regularities in real food webs: it proposes a novel theory unifying many of these regularities, as well as extensive empirical data. After a general introduction, reviewing the empirical and theoretical discoveries about food webs, the second portion of the book shows that community food webs obey several striking phenomenological regularities. Some of these unify, regardless of habitat. Others differentiate, showing that habitat significantly influences structure. The third portion of the book presents a theoretical analysis of some of the unifying empirical regularities. The fourth portion of the book presents 113 community food webs. Collected from scattered sources and carefully edited, they are the empirical basis for the results in the volume. The largest available set of data on community food webs provides a valuable foundation for future studies of community food webs. The book is intended for graduate students, teachers and researchers primarily in ecology. The theoretical portions of the book provide materials useful to teachers of applied combinatorics, in particular, random graphs. Researchers in random graphs will find here unsolved mathematical problems.

Food Webs

Food Webs PDF Author: Gary A. Polis
Publisher: Springer Science & Business Media
ISBN: 1461570077
Category : Science
Languages : en
Pages : 475

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Book Description
Reflecting the recent surge of activity in food web research fueled by new empirical data, this authoritative volume successfully spans and integrates the areas of theory, basic empirical research, applications, and resource problems. Written by recognized leaders from various branches of ecological research, this work provides an in-depth treatment of the most recent advances in the field and examines the complexity and variability of food webs through reviews, new research, and syntheses of the major issues in food web research. Food Webs features material on the role of nutrients, detritus and microbes in food webs, indirect effects in food webs, the interaction of productivity and consumption, linking cause and effect in food webs, temporal and spatial scales of food web dynamics, applications of food webs to pest management, fisheries, and ecosystem stress. Three comprehensive chapters synthesize important information on the role of indirect effects, productivity and consumer regulation, and temporal, spatial and life history influences on food webs. In addition, numerous tables, figures, and mathematical equations found nowhere else in related literature are presented in this outstanding work. Food Webs offers researchers and graduate students in various branches of ecology an extensive examination of the subject. Ecologists interested in food webs or community ecology will also find this book an invaluable tool for understanding the current state of knowledge of food web research.

Food Webs and Niche Space. (MPB-11), Volume 11

Food Webs and Niche Space. (MPB-11), Volume 11 PDF Author: Joel E. Cohen
Publisher: Princeton University Press
ISBN: 0691209448
Category : Science
Languages : en
Pages : 210

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Book Description
What is the minimum dimension of a niche space necessary to represent the overlaps among observed niches? This book presents a new technique for obtaining a partial answer to this elementary question about niche space. The author bases his technique on a relation between the combinatorial structure of food webs and the mathematical theory of interval graphs. Professor Cohen collects more than thirty food webs from the ecological literature and analyzes their statistical and combinatorial properties in detail. As a result, he is able to generalize: within habitats of a certain limited physical and temporal heterogeneity, the overlaps among niches, along their trophic (feeding) dimensions, can be represented in a one-dimensional niche space far more often than would be expected by chance alone and perhaps always. This compatibility has not previously been noticed. It indicates that real food webs fall in a small subset of the mathematically possible food webs. Professor Cohen discusses other apparently new features of real food webs, including the constant ratio of the number of kinds of prey to the number of kinds of predators in food webs that describe a community. In conclusion he discusses possible extensions and limitations of his results and suggests directions for future research.

Community Ecology

Community Ecology PDF Author: Alan Hastings
Publisher: Springer Science & Business Media
ISBN: 3642859364
Category : Science
Languages : en
Pages : 140

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Book Description
This book presents the proceedings of a workshop on community ecology organized at Davis, in April, 1986, sponsored by the Sloan Foundation. There have been several recent symposia on community ecology (Strong et. al., 1984, Diamond and Case, 1987) which have covered a wide range of topics. The goal of the workshop at Davis was more narrow: to explore the role of scale in developing a theoretical approach to understanding communities. There are a number of aspects of scale that enter into attempts to understand ecological communities. One of the most basic is organizational scale. Should community ecology proceed by building up from population biology? This question and its ramifications are stressed throughout the book and explored in the first chapter by Simon Levin. Notions of scale have long been important in understanding physical systems. Thus, in understanding the interactions of organisms with their physical environment, questions of scale become paramount. These more physical questions illustrate the role scale plays in understanding ecology, and are discussed in chapter two by Akira Okubo.

Community Ecology

Community Ecology PDF Author: Peter J. Morin
Publisher: John Wiley & Sons
ISBN: 1444341944
Category : Science
Languages : en
Pages : 731

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Book Description
All life on earth occurs in natural assemblages called communities. Community ecology is the study of patterns and processes involving these collections of two or more species. Communities are typically studied using a diversity of techniques, including observations of natural history, statistical descriptions of natural patterns, laboratory and field experiments, and mathematical modelling. Community patterns arise from a complex assortment of processes including competition, predation, mutualism, indirect effects, habitat selection, which result in the most complex biological entities on earth – including iconic systems such as rain forests and coral reefs. This book introduces the reader to a balanced coverage of concepts and theories central to community ecology, using examples drawn from terrestrial, freshwater, and marine systems, and focusing on animal, plant, and microbial species. The historical development of key concepts is described using descriptions of classic studies, while examples of exciting new developments in recent studies are used to point toward future advances in our understanding of community organization. Throughout, there is an emphasis on the crucial interplay between observations, experiments, and mathematical models. This second updated edition is a valuable resource for advanced undergraduates, graduate students, and established scientists who seek a broad overview of community ecology. The book has developed from a course in community ecology that has been taught by the author since 1983. Figures and tables can be downloaded for free from www.wiley.com/go/morin/communityecology

Community Ecology

Community Ecology PDF Author: Herman A. Verhoef
Publisher: Oxford University Press
ISBN: 0199228973
Category : Science
Languages : en
Pages : 266

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Book Description
Community ecology is the study of the interactions between populations of co-existing species. Co-edited by two prominent community ecologists and featuring contributions from top researchers in the field, this book provides a survey of the state-of-the-art in both the theory and applications of the discipline. It pays special attention to topology, dynamics, and the importance of spatial and temporal scale while also looking at applications to emerging problems in human-dominated ecosystems (including the restoration and reconstruction of viable communities). Community Ecology: Processes, Models, and Applications adopts a mainly theoretical approach and focuses on the use of network-based theory, which remains little explored in standard community ecology textbooks. The book includes discussion of the effects of biotic invasions on natural communities; the linking of ecological network structure to empirically measured community properties and dynamics; the effects of evolution on community patterns and processes; and the integration of fundamental interactions into ecological networks. A final chapter indicates future research directions for the discipline.

Advances in Ecological Research

Advances in Ecological Research PDF Author:
Publisher: Academic Press
ISBN: 0080567088
Category : Science
Languages : en
Pages : 425

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Book Description
The six articles in this issue of Advances in Ecological Research cover a wide spectrum of ecology to ecology to munities, the discussion of vegetation change on a longer time scale, and the significance of conservation, especially in the industrialized world.S.J. Hall and D.G. Raff provide something of interest to all ecologists. Several common themes are presented in this volume including the dynamics of communities with such examples as Glacier Bat and Mount St.Helens.* SPECIAL FEATURES:* Lively selection of review on topical subjects.

Community Ecology and Salamander Guilds

Community Ecology and Salamander Guilds PDF Author: Nelson G. Hairston
Publisher: Cambridge University Press
ISBN: 0521325781
Category : Science
Languages : en
Pages : 246

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Book Description
This informative book, first published in 1987, presents the theories of community ecology within the context of a natural example. The text describes and examines issues in community ecology and shows how research on salamanders has helped to solve some of the problems surrounding the theories. Salamanders exist in stable populations of the kind assumed in community theory and are more appropriate than most other animals for research on the applications of that theory. The interesting and meaningful results, collected from observation on these excellent subjects posed challenges to beliefs within community ecology. Life histories of salamanders, fieldwork in distinctly differing habitats, competition, predation and evolution are discussed in an easily readable text. Professional ecologists and students of community ecology and herpetology will be interedted in the information synthesised in this book.

Graph Theory and Its Applications to Problems of Society

Graph Theory and Its Applications to Problems of Society PDF Author: Fred S. Roberts
Publisher: SIAM
ISBN: 9781611970401
Category : Mathematics
Languages : en
Pages : 127

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Book Description
Explores modern topics in graph theory and its applications to problems in transportation, genetics, pollution, perturbed ecosystems, urban services, and social inequalities. The author presents both traditional and relatively atypical graph-theoretical topics to best illustrate applications.