Jason S. Link, William T. Stockhausen, William T. Stockhausen, and Elizabeth T. Methratta
- Published in print:
- 2005
- Published Online:
- September 2007
- ISBN:
- 9780198564836
- eISBN:
- 9780191713828
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198564836.003.0010
- Subject:
- Biology, Aquatic Biology
This chapter examines recent case studies of marine food webs to evaluate the applicability of food web theories for the marine environment. Classical macrodescriptors and recent network metrics are ...
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This chapter examines recent case studies of marine food webs to evaluate the applicability of food web theories for the marine environment. Classical macrodescriptors and recent network metrics are evaluated for each marine food web example. Food webs are defined as those which are non-estuarine, non-coastal, and larger in scale than food webs typically and classically studied (i.e., not a bay, not a river-ocean mixing zone, not a rocky inter-tidal zone, etc.). There are clear distinctions for marine food webs when compared to all terrestrial and other aquatic food webs, yet there are also clear distinctions among different types of marine food webs. The chapter notes that there are three categories of food web theories: (i) those factors and models which apply categorically to all food webs; (ii) those factors and models which can be split into simple, lowly connected, strongly interacting, clearly defined localized food webs versus complex, highly connected, weakly interacting, broader, more extensive food webs; and (iii) those factors and models which are uniquely and distinctly marine. Understanding the qualitative properties of food webs can provide further evaluation of which theories are appropriate, which are not, when each is true, and why. Finally, the chapter discusses the applications and implications of these theories for ecosystem-based natural resource management.Less
This chapter examines recent case studies of marine food webs to evaluate the applicability of food web theories for the marine environment. Classical macrodescriptors and recent network metrics are evaluated for each marine food web example. Food webs are defined as those which are non-estuarine, non-coastal, and larger in scale than food webs typically and classically studied (i.e., not a bay, not a river-ocean mixing zone, not a rocky inter-tidal zone, etc.). There are clear distinctions for marine food webs when compared to all terrestrial and other aquatic food webs, yet there are also clear distinctions among different types of marine food webs. The chapter notes that there are three categories of food web theories: (i) those factors and models which apply categorically to all food webs; (ii) those factors and models which can be split into simple, lowly connected, strongly interacting, clearly defined localized food webs versus complex, highly connected, weakly interacting, broader, more extensive food webs; and (iii) those factors and models which are uniquely and distinctly marine. Understanding the qualitative properties of food webs can provide further evaluation of which theories are appropriate, which are not, when each is true, and why. Finally, the chapter discusses the applications and implications of these theories for ecosystem-based natural resource management.
Michio Kondoh
- Published in print:
- 2005
- Published Online:
- September 2007
- ISBN:
- 9780198564836
- eISBN:
- 9780191713828
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198564836.003.0012
- Subject:
- Biology, Aquatic Biology
How do diverse species coexist in the complex networks of prey-predator interactions in nature? While most theoretical models predict that complex food webs do not persist, recent empirical studies ...
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How do diverse species coexist in the complex networks of prey-predator interactions in nature? While most theoretical models predict that complex food webs do not persist, recent empirical studies have revealed the very complex structure of natural food webs. This discrepancy between theory and observation implies that essential factors stabilizing natural food webs are lacking from previous models. This chapter reviews these studies on food web complexity and its community-level consequences. It contends that the architectural flexibility arising from foraging adaptation of consumer species is key to explaining linkage patterns and persistent mechanisms of complex food webs. A novel hypothesis is presented, which relates the complexity-stability relationship to evolutionarily history of the community.Less
How do diverse species coexist in the complex networks of prey-predator interactions in nature? While most theoretical models predict that complex food webs do not persist, recent empirical studies have revealed the very complex structure of natural food webs. This discrepancy between theory and observation implies that essential factors stabilizing natural food webs are lacking from previous models. This chapter reviews these studies on food web complexity and its community-level consequences. It contends that the architectural flexibility arising from foraging adaptation of consumer species is key to explaining linkage patterns and persistent mechanisms of complex food webs. A novel hypothesis is presented, which relates the complexity-stability relationship to evolutionarily history of the community.
Enric Sala and George Sugihara
- Published in print:
- 2005
- Published Online:
- September 2007
- ISBN:
- 9780198564836
- eISBN:
- 9780191713828
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198564836.003.0014
- Subject:
- Biology, Aquatic Biology
Marine conservation priorities have been established mostly on the basis of species and habitat diversity, but little attention has been paid to food web diversity. Ecologists are aware of the ...
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Marine conservation priorities have been established mostly on the basis of species and habitat diversity, but little attention has been paid to food web diversity. Ecologists are aware of the dynamic nature of marine food webs, and of the simplification of food web structure by anthropogenic activities, mainly fishing. Transient food web structures along gradients of fishing pressure are an analogue to stages along a successional gradient. This chapter describes regularities in food web structure along these gradients, and explores the global initial conditions (e.g., availability of species, sequence of species additions) needed to ensure that marine food webs will continue to function and adapt to environmental change in a world with increasing anthropogenic disturbance.Less
Marine conservation priorities have been established mostly on the basis of species and habitat diversity, but little attention has been paid to food web diversity. Ecologists are aware of the dynamic nature of marine food webs, and of the simplification of food web structure by anthropogenic activities, mainly fishing. Transient food web structures along gradients of fishing pressure are an analogue to stages along a successional gradient. This chapter describes regularities in food web structure along these gradients, and explores the global initial conditions (e.g., availability of species, sequence of species additions) needed to ensure that marine food webs will continue to function and adapt to environmental change in a world with increasing anthropogenic disturbance.
Guy Woodward, Ross Thompson, Colin R. Townsend, and Alan G. Hildrew
- Published in print:
- 2005
- Published Online:
- September 2007
- ISBN:
- 9780198564836
- eISBN:
- 9780191713828
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198564836.003.0006
- Subject:
- Biology, Aquatic Biology
Studies on streams provide some of the most detailed and best resolved webs yet available, and provide a means to test food web theory. These systems can be used to test patterns in connectance webs ...
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Studies on streams provide some of the most detailed and best resolved webs yet available, and provide a means to test food web theory. These systems can be used to test patterns in connectance webs and the effect of sampling on the patterns evident. The role of body-size in stream webs is reviewed. This chapter deals with attempts to quantify food webs by measures of energy flow and interaction strengths, and to characterize the circumstances leading to the presence or absence of trophic cascades in food webs. Streams are strongly linked through their food webs with surrounding systems, such as ground water and flood plains, and such cross-system subsidies is considered. The effect of natural and anthropogenic disturbances on food web attributes is addressed. Finally, the relationship between biodiversity/ecosystem functions in stream webs is addressed in the context of environmental stress.Less
Studies on streams provide some of the most detailed and best resolved webs yet available, and provide a means to test food web theory. These systems can be used to test patterns in connectance webs and the effect of sampling on the patterns evident. The role of body-size in stream webs is reviewed. This chapter deals with attempts to quantify food webs by measures of energy flow and interaction strengths, and to characterize the circumstances leading to the presence or absence of trophic cascades in food webs. Streams are strongly linked through their food webs with surrounding systems, such as ground water and flood plains, and such cross-system subsidies is considered. The effect of natural and anthropogenic disturbances on food web attributes is addressed. Finally, the relationship between biodiversity/ecosystem functions in stream webs is addressed in the context of environmental stress.
Coleen L. Moloney, Astrid Jarre, Shingo Kimura, David L. Mackas, Olivier Maury, Eugene J. Murphy, William T. Peterson, Jeffrey A. Runge, and Kazuaki Tadokoro
- Published in print:
- 2010
- Published Online:
- May 2010
- ISBN:
- 9780199558025
- eISBN:
- 9780191721939
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199558025.003.0007
- Subject:
- Biology, Biodiversity / Conservation Biology, Aquatic Biology
GLOBEC studies focused on biological—physical interactions of target species in different study regions, emphasizing responses of organisms to varying physical forces. Population‐level processes were ...
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GLOBEC studies focused on biological—physical interactions of target species in different study regions, emphasizing responses of organisms to varying physical forces. Population‐level processes were shown to be important, with ecological responses often being ecosystem‐specific. The timing of biological events (e.g. spring bloom, entry/exit from diapause, and fish spawning) is susceptible to environmental change. Many species can adapt their feeding modes and diets, but changes in mortality imposed by heavy fishing can disrupt biological systems, making them increasingly vulnerable to perturbations. Some organisms can move away from unfavourable conditions, changing the vertical and horizontal linkages between disparate ecosystems with unknown consequences. Trophic controls in food webs vary over time and space and food web structures also change, both over the short term and through shifts in regimes, sometimes irreversibly. There is an ongoing requirement to integrate ecological processes, from biogeochemistry to top predators, to understand potential consequences of global change.Less
GLOBEC studies focused on biological—physical interactions of target species in different study regions, emphasizing responses of organisms to varying physical forces. Population‐level processes were shown to be important, with ecological responses often being ecosystem‐specific. The timing of biological events (e.g. spring bloom, entry/exit from diapause, and fish spawning) is susceptible to environmental change. Many species can adapt their feeding modes and diets, but changes in mortality imposed by heavy fishing can disrupt biological systems, making them increasingly vulnerable to perturbations. Some organisms can move away from unfavourable conditions, changing the vertical and horizontal linkages between disparate ecosystems with unknown consequences. Trophic controls in food webs vary over time and space and food web structures also change, both over the short term and through shifts in regimes, sometimes irreversibly. There is an ongoing requirement to integrate ecological processes, from biogeochemistry to top predators, to understand potential consequences of global change.
Tim R. McClanahan and George M. Branch
- Published in print:
- 2008
- Published Online:
- May 2008
- ISBN:
- 9780195319958
- eISBN:
- 9780199869596
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780195319958.003.0009
- Subject:
- Biology, Aquatic Biology
This chapter summarizes what the authors consider to be the key and general organizing principles of kelp forests and coral reefs along gradients of oceanography, latitude, and effects of fishing and ...
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This chapter summarizes what the authors consider to be the key and general organizing principles of kelp forests and coral reefs along gradients of oceanography, latitude, and effects of fishing and resource use on these ecosystems. The general structure of these food webs is described as well as the effects of top-down versus bottom-up controls and the prevalence of trophic cascades. Human effects and recommendations for management are presented.Less
This chapter summarizes what the authors consider to be the key and general organizing principles of kelp forests and coral reefs along gradients of oceanography, latitude, and effects of fishing and resource use on these ecosystems. The general structure of these food webs is described as well as the effects of top-down versus bottom-up controls and the prevalence of trophic cascades. Human effects and recommendations for management are presented.
Dietmar Straile
- Published in print:
- 2005
- Published Online:
- September 2007
- ISBN:
- 9780198564836
- eISBN:
- 9780191713828
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198564836.003.0005
- Subject:
- Biology, Aquatic Biology
Studies on lakes provide some of the most complete investigations on the structure, dynamics, and energetics of food webs encompassing organisms from bacteria to vertebrates. The life cycle of ...
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Studies on lakes provide some of the most complete investigations on the structure, dynamics, and energetics of food webs encompassing organisms from bacteria to vertebrates. The life cycle of organisms in temperate lakes is adapted to a highly seasonal environment. Food web interactions in these lakes depend on the seasonal overlap of the occurrence of potential prey, competitor, or predator species. This seasonal overlap (i.e., the match-mismatch of food web interactions) depends strongly on the seasonal dynamics of the physical environment of lakes, such as temperature, light availability, and mixing intensity. Consequently, climate variability influences food web interactions and hence the structure, dynamics, and energetics of lake food webs. This chapter provides examples and discusses the importance of seasonality for the understanding of various aspects of lake food webs and the impact of climate variability thereon.Less
Studies on lakes provide some of the most complete investigations on the structure, dynamics, and energetics of food webs encompassing organisms from bacteria to vertebrates. The life cycle of organisms in temperate lakes is adapted to a highly seasonal environment. Food web interactions in these lakes depend on the seasonal overlap of the occurrence of potential prey, competitor, or predator species. This seasonal overlap (i.e., the match-mismatch of food web interactions) depends strongly on the seasonal dynamics of the physical environment of lakes, such as temperature, light availability, and mixing intensity. Consequently, climate variability influences food web interactions and hence the structure, dynamics, and energetics of lake food webs. This chapter provides examples and discusses the importance of seasonality for the understanding of various aspects of lake food webs and the impact of climate variability thereon.
Kevin S. McCann
- Published in print:
- 2011
- Published Online:
- October 2017
- ISBN:
- 9780691134178
- eISBN:
- 9781400840687
- Item type:
- chapter
- Publisher:
- Princeton University Press
- DOI:
- 10.23943/princeton/9780691134178.003.0009
- Subject:
- Biology, Ecology
This chapter examines food webs at the landscape scale by focusing on the large-scale food web architecture that is deeply constrained by space. It begins with a discussion of how variability in ...
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This chapter examines food webs at the landscape scale by focusing on the large-scale food web architecture that is deeply constrained by space. It begins with a discussion of how variability in space, time, and food web structure, coupled with the ability of organisms to rapidly respond to variation, affect the maintenance of the food web and its functions. It then explains how individual traits such as body size and foraging behavior relate to food web structure in space and time. It also considers the role of spatial constraints on food webs and how the existence of fast–slow pathways coupled by mobile adaptive predators gives rise to spatial asynchrony in the resources. The chapter concludes with a review of some empirical examples to show that some food webs display the bird feeder effect and that resource coupling of distinct habitats appears to stabilize food webs.Less
This chapter examines food webs at the landscape scale by focusing on the large-scale food web architecture that is deeply constrained by space. It begins with a discussion of how variability in space, time, and food web structure, coupled with the ability of organisms to rapidly respond to variation, affect the maintenance of the food web and its functions. It then explains how individual traits such as body size and foraging behavior relate to food web structure in space and time. It also considers the role of spatial constraints on food webs and how the existence of fast–slow pathways coupled by mobile adaptive predators gives rise to spatial asynchrony in the resources. The chapter concludes with a review of some empirical examples to show that some food webs display the bird feeder effect and that resource coupling of distinct habitats appears to stabilize food webs.
Kevin S. McCann
- Published in print:
- 2011
- Published Online:
- October 2017
- ISBN:
- 9780691134178
- eISBN:
- 9781400840687
- Item type:
- chapter
- Publisher:
- Princeton University Press
- DOI:
- 10.23943/princeton/9780691134178.003.0012
- Subject:
- Biology, Ecology
This chapter examines some of the potential empirical signatures of instability in complex adaptive food webs. It first considers the role of adaptive behavior on food web topology, ecosystem size, ...
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This chapter examines some of the potential empirical signatures of instability in complex adaptive food webs. It first considers the role of adaptive behavior on food web topology, ecosystem size, and interaction strength before discussing the implications of this behavior for ecosystem dynamics and stability. It then analyzes the results of empirical investigations of Canadian Shield lake trout food webs and how human influences and ecosystems coupled in space may drive biomass pyramids, potentially leading to species loss. It also explores the tendency of subsidies, through human impacts, to homogenize natural ecosytems and concludes by assessing some of the changing conditions that are being driven by humans and how these may change ecosystems.Less
This chapter examines some of the potential empirical signatures of instability in complex adaptive food webs. It first considers the role of adaptive behavior on food web topology, ecosystem size, and interaction strength before discussing the implications of this behavior for ecosystem dynamics and stability. It then analyzes the results of empirical investigations of Canadian Shield lake trout food webs and how human influences and ecosystems coupled in space may drive biomass pyramids, potentially leading to species loss. It also explores the tendency of subsidies, through human impacts, to homogenize natural ecosytems and concludes by assessing some of the changing conditions that are being driven by humans and how these may change ecosystems.
Helmut Hillebrand and Jonathan B. Shurin
- Published in print:
- 2005
- Published Online:
- September 2007
- ISBN:
- 9780198564836
- eISBN:
- 9780191713828
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198564836.003.0015
- Subject:
- Biology, Aquatic Biology
Biodiversity in freshwater food webs can be considered in terms of the number of species occupying unique trophic positions or the number of species within a trophic position. Either can affect ...
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Biodiversity in freshwater food webs can be considered in terms of the number of species occupying unique trophic positions or the number of species within a trophic position. Either can affect energy flow or biomass partitioning, and the two aspects of diversity may feed back on one another. This chapter analyses the importance of biodiversity in aquatic food webs on three different levels. First, it asks how varying diversity within trophic groups affects the outcome of trophic interactions. It then presents a conceptual framework and contrasts this model against experimental manipulations of consumer or prey diversity. Second, it asks how consumers and resources affect biodiversity within trophic levels. This question has a long history of experimental and modeling studies, and these are reviewed. The role of biodiversity at local and regional spatial scales for freshwater food webs is examined. Dispersal among local habitats can constrain local species diversity and influence the outcome of food web interactions. The interactive effects of the regional pool versus resident diversity on the outcome of trophic interactions are discussed.Less
Biodiversity in freshwater food webs can be considered in terms of the number of species occupying unique trophic positions or the number of species within a trophic position. Either can affect energy flow or biomass partitioning, and the two aspects of diversity may feed back on one another. This chapter analyses the importance of biodiversity in aquatic food webs on three different levels. First, it asks how varying diversity within trophic groups affects the outcome of trophic interactions. It then presents a conceptual framework and contrasts this model against experimental manipulations of consumer or prey diversity. Second, it asks how consumers and resources affect biodiversity within trophic levels. This question has a long history of experimental and modeling studies, and these are reviewed. The role of biodiversity at local and regional spatial scales for freshwater food webs is examined. Dispersal among local habitats can constrain local species diversity and influence the outcome of food web interactions. The interactive effects of the regional pool versus resident diversity on the outcome of trophic interactions are discussed.
Owen L. Petchey, Peter J. Morin, and Han Olff
- Published in print:
- 2009
- Published Online:
- February 2010
- ISBN:
- 9780199228973
- eISBN:
- 9780191711169
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199228973.003.0002
- Subject:
- Biology, Ecology
This chapter considers topology, i.e. the shape and structure of networks of interacting organisms in ecological systems. Species often form the nodes of such networks, though life stages, age ...
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This chapter considers topology, i.e. the shape and structure of networks of interacting organisms in ecological systems. Species often form the nodes of such networks, though life stages, age classes or functional groups are sometimes equally applicable. The links between nodes in ecological networks can have a variety of meanings, in particular they can represent transfer of energy or material, they can represent the net effect on fitness or population size (direct and/or indirect) of one species on another, or represent the exchange of information. These differences create at least three types of interaction networks: competition networks, mutualistic networks and food webs (consumption networks), all of which are subsets of the full network of interactions in any community.Less
This chapter considers topology, i.e. the shape and structure of networks of interacting organisms in ecological systems. Species often form the nodes of such networks, though life stages, age classes or functional groups are sometimes equally applicable. The links between nodes in ecological networks can have a variety of meanings, in particular they can represent transfer of energy or material, they can represent the net effect on fitness or population size (direct and/or indirect) of one species on another, or represent the exchange of information. These differences create at least three types of interaction networks: competition networks, mutualistic networks and food webs (consumption networks), all of which are subsets of the full network of interactions in any community.
Rodrigo H. Bustamante, Thomas A. Okey, and Stuart Banks
- Published in print:
- 2008
- Published Online:
- May 2008
- ISBN:
- 9780195319958
- eISBN:
- 9780199869596
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780195319958.003.0006
- Subject:
- Biology, Aquatic Biology
This chapter describes ecology of the Galapagos rocky reef system and the important role of biogeographic position on biodiversity, the El Niño cycle, and the history of resource extraction on the ...
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This chapter describes ecology of the Galapagos rocky reef system and the important role of biogeographic position on biodiversity, the El Niño cycle, and the history of resource extraction on the current state of the ecosystem. The chapter presents a model of the energetic pathways in the ecosystem and its predictions for fisheries yields and the role of key species. The history of exploitation is outlined as well as the role of the current marine protected areas to develop sustainable management system.Less
This chapter describes ecology of the Galapagos rocky reef system and the important role of biogeographic position on biodiversity, the El Niño cycle, and the history of resource extraction on the current state of the ecosystem. The chapter presents a model of the energetic pathways in the ecosystem and its predictions for fisheries yields and the role of key species. The history of exploitation is outlined as well as the role of the current marine protected areas to develop sustainable management system.
Frédéric Thomas, François Renaud, and Jean-François Guegan (eds)
- Published in print:
- 2005
- Published Online:
- September 2007
- ISBN:
- 9780198529873
- eISBN:
- 9780191712777
- Item type:
- book
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198529873.001.0001
- Subject:
- Biology, Disease Ecology / Epidemiology
Ecologists, epidemiologists, and evolutionary biologists are increasingly aware of the significance of parasites in the study of ecosystems. This book provides a summary of the issues involved as ...
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Ecologists, epidemiologists, and evolutionary biologists are increasingly aware of the significance of parasites in the study of ecosystems. This book provides a summary of the issues involved as well as an overview of the possibilities offered by this research topic, using well-documented case-studies to illustrate the main trends and prospects in this area. This is the first book devoted to the comprehension of both the roles and consequences of pathogens in ecosystems.Less
Ecologists, epidemiologists, and evolutionary biologists are increasingly aware of the significance of parasites in the study of ecosystems. This book provides a summary of the issues involved as well as an overview of the possibilities offered by this research topic, using well-documented case-studies to illustrate the main trends and prospects in this area. This is the first book devoted to the comprehension of both the roles and consequences of pathogens in ecosystems.
Warwick F. Vincent and Johanna Laybourn-Parry (eds)
- Published in print:
- 2008
- Published Online:
- January 2009
- ISBN:
- 9780199213887
- eISBN:
- 9780191707506
- Item type:
- book
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199213887.001.0001
- Subject:
- Biology, Ecology, Aquatic Biology
Lakes, ponds, rivers and streams are prominent features of the Arctic landscape and are also common in many parts of Antarctica. These waters encompass a remarkable variety of conditions for aquatic ...
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Lakes, ponds, rivers and streams are prominent features of the Arctic landscape and are also common in many parts of Antarctica. These waters encompass a remarkable variety of conditions for aquatic life, and are proving to be attractive model systems for exploring general ecological themes. Some of these ecosystems have direct global implications, and are also sentinels of global climate change. This book brings together many of the world's leading researchers in polar limnology to describe these diverse aquatic environments and their ecology. It introduces each major ecosystem type including extreme ice shelf and glacial meltwaters; subglacial lakes and rivers; perennially ice-capped lakes; meromictic and epishelf lake systems; tundra lakes and ponds; seasonal streams; and the large Arctic rivers with their associated floodplain lakes. Separate chapters review the geomorphology of polar lake basins, high latitude paleolimnology; biogeochemistry; physical limnology; microbial processes; microbial biodiversity and biogeography; benthic photosynthetic communities including microbial mats and mosses; phytoplankton and primary production; zooplankton and benthic invertebrates; the ecology of high Arctic fish; food web structure and dynamics; and new and emerging themes in high latitude limnology. The book incorporates the overriding theme of climate change impacts as well as direct impacts resulting from human activity.Less
Lakes, ponds, rivers and streams are prominent features of the Arctic landscape and are also common in many parts of Antarctica. These waters encompass a remarkable variety of conditions for aquatic life, and are proving to be attractive model systems for exploring general ecological themes. Some of these ecosystems have direct global implications, and are also sentinels of global climate change. This book brings together many of the world's leading researchers in polar limnology to describe these diverse aquatic environments and their ecology. It introduces each major ecosystem type including extreme ice shelf and glacial meltwaters; subglacial lakes and rivers; perennially ice-capped lakes; meromictic and epishelf lake systems; tundra lakes and ponds; seasonal streams; and the large Arctic rivers with their associated floodplain lakes. Separate chapters review the geomorphology of polar lake basins, high latitude paleolimnology; biogeochemistry; physical limnology; microbial processes; microbial biodiversity and biogeography; benthic photosynthetic communities including microbial mats and mosses; phytoplankton and primary production; zooplankton and benthic invertebrates; the ecology of high Arctic fish; food web structure and dynamics; and new and emerging themes in high latitude limnology. The book incorporates the overriding theme of climate change impacts as well as direct impacts resulting from human activity.
Kevin S. McCann
- Published in print:
- 2011
- Published Online:
- October 2017
- ISBN:
- 9780691134178
- eISBN:
- 9781400840687
- Item type:
- chapter
- Publisher:
- Princeton University Press
- DOI:
- 10.23943/princeton/9780691134178.003.0007
- Subject:
- Biology, Ecology
This chapter extends the consumer–resource theory to include simple but common three-species modules behind the construction of whole food webs, with particular emphasis on food chains and omnivory. ...
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This chapter extends the consumer–resource theory to include simple but common three-species modules behind the construction of whole food webs, with particular emphasis on food chains and omnivory. It first considers some common simple modular food web structures and whether the dynamics of subsystems can be seen using the framework laid out in previous chapters. Specifically, it asks when common food web structure increases or weakens the relative interaction strengths and/or when a food web structure modifies flux between consumers and resources in a density-dependent manner such that the food web tends to increase flux rates in some situations and decrease the coupling in other situations. The chapter also explores how stage structure can influence food chain stability before concluding with a review of empirical evidence on the dynamical implications of omnivory for food webs.Less
This chapter extends the consumer–resource theory to include simple but common three-species modules behind the construction of whole food webs, with particular emphasis on food chains and omnivory. It first considers some common simple modular food web structures and whether the dynamics of subsystems can be seen using the framework laid out in previous chapters. Specifically, it asks when common food web structure increases or weakens the relative interaction strengths and/or when a food web structure modifies flux between consumers and resources in a density-dependent manner such that the food web tends to increase flux rates in some situations and decrease the coupling in other situations. The chapter also explores how stage structure can influence food chain stability before concluding with a review of empirical evidence on the dynamical implications of omnivory for food webs.
Nicolas Loeuille and Michel Loreau
- Published in print:
- 2009
- Published Online:
- February 2010
- ISBN:
- 9780199228973
- eISBN:
- 9780191711169
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199228973.003.00013
- Subject:
- Biology, Ecology
Evolutionary dynamics may help us understand the structure and dynamics of food webs. The theoretical understanding of empirical food web patterns faces a dilemma, as it is difficult to account ...
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Evolutionary dynamics may help us understand the structure and dynamics of food webs. The theoretical understanding of empirical food web patterns faces a dilemma, as it is difficult to account simultaneously for dynamical components (demography, evolution) and for the complexity of these systems (species number, connectance). Current knowledge of food web structures is dominated by many-species models that do not incorporate any dynamical aspects, and by models that detail demographic or evolutionary dynamics of species but consider communities composed of few species. Community evolution models incorporate both the dynamical components of food webs and the complexity that is necessary to understand empirical food web data.Less
Evolutionary dynamics may help us understand the structure and dynamics of food webs. The theoretical understanding of empirical food web patterns faces a dilemma, as it is difficult to account simultaneously for dynamical components (demography, evolution) and for the complexity of these systems (species number, connectance). Current knowledge of food web structures is dominated by many-species models that do not incorporate any dynamical aspects, and by models that detail demographic or evolutionary dynamics of species but consider communities composed of few species. Community evolution models incorporate both the dynamical components of food webs and the complexity that is necessary to understand empirical food web data.
L. Ciannelli, D. Ø. Hjermann, P. Lehodey, G. Ottersen, J. T. Duffy-Anderson, and N. C. Stenseth
- Published in print:
- 2005
- Published Online:
- September 2007
- ISBN:
- 9780198564836
- eISBN:
- 9780191713828
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198564836.003.0013
- Subject:
- Biology, Aquatic Biology
The Eastern Bering Sea (EBS), the Gulf of Alaska (GOA), and the Barents Sea (BS) share key features: they are dominated by gadoids populations, they are heavily fished, and they are under the ...
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The Eastern Bering Sea (EBS), the Gulf of Alaska (GOA), and the Barents Sea (BS) share key features: they are dominated by gadoids populations, they are heavily fished, and they are under the influence of large-scale climatic fluctuations. Previous studies have shown that climate forcing can impact the species composition and the food webs in each of these ecosystems. However, food webs and species interactions can mediate the relative impact of climatic perturbation on community. For example, a relatively small increase in SST over the western GOA region during the mid-1970s led to a spectacular change in the local species community, but a reverse in climatic conditions that occurred during the late 1980s did not result in similar biological changes. This chapter reviews the food webs of the GOA, EBS, and BS, and relates them to prevailing large-scale climatic phases. The comparative approach adopted in this review is aimed at increasing the understanding of the mechanisms linking climate change and food web dynamics in marine ecosystems.Less
The Eastern Bering Sea (EBS), the Gulf of Alaska (GOA), and the Barents Sea (BS) share key features: they are dominated by gadoids populations, they are heavily fished, and they are under the influence of large-scale climatic fluctuations. Previous studies have shown that climate forcing can impact the species composition and the food webs in each of these ecosystems. However, food webs and species interactions can mediate the relative impact of climatic perturbation on community. For example, a relatively small increase in SST over the western GOA region during the mid-1970s led to a spectacular change in the local species community, but a reverse in climatic conditions that occurred during the late 1980s did not result in similar biological changes. This chapter reviews the food webs of the GOA, EBS, and BS, and relates them to prevailing large-scale climatic phases. The comparative approach adopted in this review is aimed at increasing the understanding of the mechanisms linking climate change and food web dynamics in marine ecosystems.
Andrew R. Solow
- Published in print:
- 2005
- Published Online:
- September 2007
- ISBN:
- 9780198564836
- eISBN:
- 9780191713828
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198564836.003.0007
- Subject:
- Biology, Aquatic Biology
This chapter focuses on the formal statistical analysis of community food webs. Among the issues covered are testing for hypothesized regularities (e.g., constant connectance) in a collection of food ...
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This chapter focuses on the formal statistical analysis of community food webs. Among the issues covered are testing for hypothesized regularities (e.g., constant connectance) in a collection of food webs and fitting and testing parametric models (e.g., the cascade model). The analysis of partially observed food webs is also covered.Less
This chapter focuses on the formal statistical analysis of community food webs. Among the issues covered are testing for hypothesized regularities (e.g., constant connectance) in a collection of food webs and fitting and testing parametric models (e.g., the cascade model). The analysis of partially observed food webs is also covered.
Simon Jennings
- Published in print:
- 2005
- Published Online:
- September 2007
- ISBN:
- 9780198564836
- eISBN:
- 9780191713828
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198564836.003.0009
- Subject:
- Biology, Aquatic Biology
This chapter presents size-based analyses of aquatic food webs, where body size rather than species identity is the principle descriptor of an individual's role in the food web, provides insights ...
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This chapter presents size-based analyses of aquatic food webs, where body size rather than species identity is the principle descriptor of an individual's role in the food web, provides insights into food web structure and function that complement, and extends those from species-based analyses. Focus is given to body size because it underpins predator-prey interactions and dictates how the biological properties of individuals change with size. Thus, size-based food web analyses offer an approach for integrating community and ecosystem ecology with energetic and metabolic theory.Less
This chapter presents size-based analyses of aquatic food webs, where body size rather than species identity is the principle descriptor of an individual's role in the food web, provides insights into food web structure and function that complement, and extends those from species-based analyses. Focus is given to body size because it underpins predator-prey interactions and dictates how the biological properties of individuals change with size. Thus, size-based food web analyses offer an approach for integrating community and ecosystem ecology with energetic and metabolic theory.
Kevin S. McCann
- Published in print:
- 2011
- Published Online:
- October 2017
- ISBN:
- 9780691134178
- eISBN:
- 9781400840687
- Item type:
- chapter
- Publisher:
- Princeton University Press
- DOI:
- 10.23943/princeton/9780691134178.003.0010
- Subject:
- Biology, Ecology
This chapter examines the basic assumptions of classic food web theory. It first considers the classic whole-community approach, which assumes that any specific matrix represents a sample from a ...
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This chapter examines the basic assumptions of classic food web theory. It first considers the classic whole-community approach, which assumes that any specific matrix represents a sample from a “statistical universe” of interaction strengths for a given set of n species. It then describes some matrix approaches to see if context-dependent techniques can be applied to matrix theory, along with the simple graphical techniques of Gershgorin discs employed as an intuitive approach to eigenvalues. It argues that there are some rather intriguing “gravitational-like” properties of Gershgorin discs for some important biologically motivated matrices. The chapter proceeds by discussing some classic whole-matrix results that highlight the connections between the stability of lower-dimensional modules and whole food webs. Finally, it shows how the ideas derived from classic whole-system matrix approaches generally agree with the results of modular theory.Less
This chapter examines the basic assumptions of classic food web theory. It first considers the classic whole-community approach, which assumes that any specific matrix represents a sample from a “statistical universe” of interaction strengths for a given set of n species. It then describes some matrix approaches to see if context-dependent techniques can be applied to matrix theory, along with the simple graphical techniques of Gershgorin discs employed as an intuitive approach to eigenvalues. It argues that there are some rather intriguing “gravitational-like” properties of Gershgorin discs for some important biologically motivated matrices. The chapter proceeds by discussing some classic whole-matrix results that highlight the connections between the stability of lower-dimensional modules and whole food webs. Finally, it shows how the ideas derived from classic whole-system matrix approaches generally agree with the results of modular theory.
