J. Morgan Grove, Mary L. Cadenasso, Steward T. A. Pickett, Gary E. Machlis, and William R. Burch
- Published in print:
- 2015
- Published Online:
- May 2016
- ISBN:
- 9780300101133
- eISBN:
- 9780300217865
- Item type:
- chapter
- Publisher:
- Yale University Press
- DOI:
- 10.12987/yale/9780300101133.003.0003
- Subject:
- Environmental Science, Nature
This chapter lays out the concept and framework for a “patch dynamics” approach and briefly reviews its contributions to describing and quantifying patterns and changes in spatial heterogeneity of ...
More
This chapter lays out the concept and framework for a “patch dynamics” approach and briefly reviews its contributions to describing and quantifying patterns and changes in spatial heterogeneity of bioecological systems. Patch dynamics emerged in ecology as an approach to understanding spatial heterogeneity. Though ecology is its original disciplinary home, patch dynamics resonates with contemporary urban social theory. Consequently, a patch dynamics approach can serve as a critical node of synthesis between contemporary social and ecological approaches for an ecology of cities. Thus, the chapter applies patch dynamics to urban systems and demonstrates how it addresses the drivers of urban systems identified in earlier chapters.Less
This chapter lays out the concept and framework for a “patch dynamics” approach and briefly reviews its contributions to describing and quantifying patterns and changes in spatial heterogeneity of bioecological systems. Patch dynamics emerged in ecology as an approach to understanding spatial heterogeneity. Though ecology is its original disciplinary home, patch dynamics resonates with contemporary urban social theory. Consequently, a patch dynamics approach can serve as a critical node of synthesis between contemporary social and ecological approaches for an ecology of cities. Thus, the chapter applies patch dynamics to urban systems and demonstrates how it addresses the drivers of urban systems identified in earlier chapters.
J. Morgan Grove, Mary L. Cadenasso, Steward T. A. Pickett, Gary E. Machlis, and William R. Burch
- Published in print:
- 2015
- Published Online:
- May 2016
- ISBN:
- 9780300101133
- eISBN:
- 9780300217865
- Item type:
- chapter
- Publisher:
- Yale University Press
- DOI:
- 10.12987/yale/9780300101133.003.0002
- Subject:
- Environmental Science, Nature
This chapter discusses the historical connections between biophysical ecology and sociological approaches to urban ecology. This historical narrative lays the foundation for linking the study of ...
More
This chapter discusses the historical connections between biophysical ecology and sociological approaches to urban ecology. This historical narrative lays the foundation for linking the study of spatial heterogeneity in the social and economic sciences with the contemporary understanding of spatial heterogeneity in biophysical ecology that is discussed in the next chapter. To provide context to these historical connections, the chapter first gives an overview of contemporary ecology and its subdisciplines. It then describes the Chicago School of urban ecology and some of its critiques. It locates the Chicago School in the context of four dominant biological perspectives that social scientists have used for the study of cities, before concluding this historical narrative in terms of spatial and organizational complexity issues for the study of urban ecological systems.Less
This chapter discusses the historical connections between biophysical ecology and sociological approaches to urban ecology. This historical narrative lays the foundation for linking the study of spatial heterogeneity in the social and economic sciences with the contemporary understanding of spatial heterogeneity in biophysical ecology that is discussed in the next chapter. To provide context to these historical connections, the chapter first gives an overview of contemporary ecology and its subdisciplines. It then describes the Chicago School of urban ecology and some of its critiques. It locates the Chicago School in the context of four dominant biological perspectives that social scientists have used for the study of cities, before concluding this historical narrative in terms of spatial and organizational complexity issues for the study of urban ecological systems.
Kimberly A. With
- Published in print:
- 2019
- Published Online:
- August 2019
- ISBN:
- 9780198838388
- eISBN:
- 9780191874697
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/oso/9780198838388.003.0003
- Subject:
- Biology, Ecology, Biodiversity / Conservation Biology
Heterogeneity is a defining characteristic of landscapes and therefore central to the study of landscape ecology. Landscape ecology investigates what factors give rise to heterogeneity, how that ...
More
Heterogeneity is a defining characteristic of landscapes and therefore central to the study of landscape ecology. Landscape ecology investigates what factors give rise to heterogeneity, how that heterogeneity is maintained or altered by natural and anthropogenic disturbances, and how heterogeneity ultimately influences ecological processes and flows across the landscape. Because heterogeneity is expressed across a wide range of spatial scales, the landscape perspective can be applied to address these sorts of questions at any level of ecological organization, and in aquatic and marine systems as well as terrestrial ones. Disturbances—both natural and anthropogenic—are a ubiquitous feature of any landscape, contributing to its structure and dynamics. Although the focus in landscape ecology is typically on spatial heterogeneity, disturbance dynamics produce changes in landscape structure over time as well as in space. Heterogeneity and disturbance dynamics are thus inextricably linked and are therefore covered together in this chapter.Less
Heterogeneity is a defining characteristic of landscapes and therefore central to the study of landscape ecology. Landscape ecology investigates what factors give rise to heterogeneity, how that heterogeneity is maintained or altered by natural and anthropogenic disturbances, and how heterogeneity ultimately influences ecological processes and flows across the landscape. Because heterogeneity is expressed across a wide range of spatial scales, the landscape perspective can be applied to address these sorts of questions at any level of ecological organization, and in aquatic and marine systems as well as terrestrial ones. Disturbances—both natural and anthropogenic—are a ubiquitous feature of any landscape, contributing to its structure and dynamics. Although the focus in landscape ecology is typically on spatial heterogeneity, disturbance dynamics produce changes in landscape structure over time as well as in space. Heterogeneity and disturbance dynamics are thus inextricably linked and are therefore covered together in this chapter.
Lawrence R. Walker
- Published in print:
- 2011
- Published Online:
- December 2013
- ISBN:
- 9780199575299
- eISBN:
- 9780191774836
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199575299.003.0007
- Subject:
- Biology, Ecology
Disturbances contribute to the number and variety of spatial patterns at many scales and disturbance effects are best considered at a particular scale and for specific types of heterogeneity. ...
More
Disturbances contribute to the number and variety of spatial patterns at many scales and disturbance effects are best considered at a particular scale and for specific types of heterogeneity. Hierarchical analyses of scales allow a broader and more realistic integration across spatial scales than measurements of disturbance effects at only a single spatial scale. This chapter examines how spatial dynamics are compared across spatial scales; how disturbances contribute to spatial heterogeneity; the role of dispersal in creating patches; spatial heterogeneity in two very heterogeneous environments (soils and shorelines); the dynamics of habitat patches; and the contrasting spatial patterns derived from natural and anthropogenic disturbances.Less
Disturbances contribute to the number and variety of spatial patterns at many scales and disturbance effects are best considered at a particular scale and for specific types of heterogeneity. Hierarchical analyses of scales allow a broader and more realistic integration across spatial scales than measurements of disturbance effects at only a single spatial scale. This chapter examines how spatial dynamics are compared across spatial scales; how disturbances contribute to spatial heterogeneity; the role of dispersal in creating patches; spatial heterogeneity in two very heterogeneous environments (soils and shorelines); the dynamics of habitat patches; and the contrasting spatial patterns derived from natural and anthropogenic disturbances.
Kendi F. Davies
- Published in print:
- 2011
- Published Online:
- March 2012
- ISBN:
- 9780520268357
- eISBN:
- 9780520948457
- Item type:
- chapter
- Publisher:
- University of California Press
- DOI:
- 10.1525/california/9780520268357.003.0011
- Subject:
- Biology, Plant Sciences and Forestry
Invasive species are one of the most significant threats to native species diversity, and identifying the factors that make places more or less invasible has been one of the most important issues in ...
More
Invasive species are one of the most significant threats to native species diversity, and identifying the factors that make places more or less invasible has been one of the most important issues in the study of invasions. Serpentine systems have provided significant insight into the reasons some communities are more invasible than others, because the environment within these systems is often extreme. Spatial heterogeneity, spatial scale, and productivity have all proven to be critical elements in understanding the invasibility of communities. This chapter takes the following elements—spatial heterogeneity, scale, and productivity—and contrasts the contributions of studies in serpentine systems with studies in systems that are not serpentine.Less
Invasive species are one of the most significant threats to native species diversity, and identifying the factors that make places more or less invasible has been one of the most important issues in the study of invasions. Serpentine systems have provided significant insight into the reasons some communities are more invasible than others, because the environment within these systems is often extreme. Spatial heterogeneity, spatial scale, and productivity have all proven to be critical elements in understanding the invasibility of communities. This chapter takes the following elements—spatial heterogeneity, scale, and productivity—and contrasts the contributions of studies in serpentine systems with studies in systems that are not serpentine.
Samson Y. Gebreab
- Published in print:
- 2018
- Published Online:
- April 2018
- ISBN:
- 9780190843496
- eISBN:
- 9780190843533
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/oso/9780190843496.003.0004
- Subject:
- Public Health and Epidemiology, Public Health, Epidemiology
Most studies evaluating relationships between neighborhood characteristics and health neglect to examine and account for the spatial dependency across neighborhoods, that is, how neighboring areas ...
More
Most studies evaluating relationships between neighborhood characteristics and health neglect to examine and account for the spatial dependency across neighborhoods, that is, how neighboring areas are related to each other, although the possible presence of spatial effects (e.g., spatial dependency, spatial heterogeneity) can potentially influence the results in substantial ways. This chapter first discusses the concept of spatial autocorrelation and then provides an overview of different spatial clustering methods, including Moran’s I and spatial scan statistics as well as different models to map spatial data, for example, spatial Bayesian mapping. Next, this chapter discusses various spatial regression methods used in spatial epidemiology for accounting spatial dependency and/or spatial heterogeneity in modeling the relationships between neighborhood characteristics and health outcomes, including spatial econometric models, Bayesian spatial models, and multilevel spatial models.Less
Most studies evaluating relationships between neighborhood characteristics and health neglect to examine and account for the spatial dependency across neighborhoods, that is, how neighboring areas are related to each other, although the possible presence of spatial effects (e.g., spatial dependency, spatial heterogeneity) can potentially influence the results in substantial ways. This chapter first discusses the concept of spatial autocorrelation and then provides an overview of different spatial clustering methods, including Moran’s I and spatial scan statistics as well as different models to map spatial data, for example, spatial Bayesian mapping. Next, this chapter discusses various spatial regression methods used in spatial epidemiology for accounting spatial dependency and/or spatial heterogeneity in modeling the relationships between neighborhood characteristics and health outcomes, including spatial econometric models, Bayesian spatial models, and multilevel spatial models.
Graham Bell
- Published in print:
- 2007
- Published Online:
- May 2008
- ISBN:
- 9780198569725
- eISBN:
- 9780191717741
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780198569725.003.0002
- Subject:
- Biology, Evolutionary Biology / Genetics
This chapter gives some quantitative information about the rates of genetic and environmental deterioration. The first section in this chapter is about history, chance, and necessity, and includes ...
More
This chapter gives some quantitative information about the rates of genetic and environmental deterioration. The first section in this chapter is about history, chance, and necessity, and includes subsections on Lamarckian evolution; the selection of undirected variation; descent; and delection. The second section is about drift and includes subsections concerning the rate of genetic deterioration; two scaled mutation rates; the rate of deleterious mutation; decay of isolate lines in the absence of selection; mutation rate in other replicators; mutation rate in stressful environments; the genomic mutation rate; the effect of mutations; beneficial mutations; the effect of gene deletion on growth; the rate of accumulation of genetic variance in fitness; the replication limit; the size spectrum; the distribution of species abundance; and finally genetic variation and species abundance. The final section is on the rate of environmental deterioration. Subsections in this section concern aggregation; the ecological population concept; dispersal; and the genetic population concept. Five theories of the environment are offered and environmental variation in space; environmental variation over time; and the biotic environment are also detailed.Less
This chapter gives some quantitative information about the rates of genetic and environmental deterioration. The first section in this chapter is about history, chance, and necessity, and includes subsections on Lamarckian evolution; the selection of undirected variation; descent; and delection. The second section is about drift and includes subsections concerning the rate of genetic deterioration; two scaled mutation rates; the rate of deleterious mutation; decay of isolate lines in the absence of selection; mutation rate in other replicators; mutation rate in stressful environments; the genomic mutation rate; the effect of mutations; beneficial mutations; the effect of gene deletion on growth; the rate of accumulation of genetic variance in fitness; the replication limit; the size spectrum; the distribution of species abundance; and finally genetic variation and species abundance. The final section is on the rate of environmental deterioration. Subsections in this section concern aggregation; the ecological population concept; dispersal; and the genetic population concept. Five theories of the environment are offered and environmental variation in space; environmental variation over time; and the biotic environment are also detailed.
T. Alex Perkins, Guido España, Sean M. Moore, Rachel J. Oidtman, Swarnali Sharma, Brajendra Singh, Amir S. Siraj, K. James Soda, Morgan Smith, Magdalene K. Walters, and Edwin Michael
- Published in print:
- 2020
- Published Online:
- February 2021
- ISBN:
- 9780198853244
- eISBN:
- 9780191887710
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/oso/9780198853244.003.0003
- Subject:
- Biology, Disease Ecology / Epidemiology, Ecology
Prediction of spatial heterogeneity in disease incidence based on measurable spatial factors is a major goal of spatial epidemiology. There are a number of applied goals of these predictions, ...
More
Prediction of spatial heterogeneity in disease incidence based on measurable spatial factors is a major goal of spatial epidemiology. There are a number of applied goals of these predictions, including appropriately targeting resources for surveillance and intervention and accurately quantifying disease burden. Although spatial heterogeneity is evident in the epidemiology of many diseases, several aspects of the biology of vector-borne diseases amplify this form of heterogeneity. Here, we review several aspects of this biology, highlighting seven distinct ways in which the biology of vector-borne diseases impacts understanding spatial heterogeneity in disease incidence. Whereas traditional methods place emphasis on spatial regression and other forms of statistical analysis of empirical data, the goal here is to offer a perspective on potential pitfalls of analyses that take data at face value and do not acknowledge the complex, nonlinear, and dynamic relationships between spatial patterns of disease incidence and spatial heterogeneity in transmission.Less
Prediction of spatial heterogeneity in disease incidence based on measurable spatial factors is a major goal of spatial epidemiology. There are a number of applied goals of these predictions, including appropriately targeting resources for surveillance and intervention and accurately quantifying disease burden. Although spatial heterogeneity is evident in the epidemiology of many diseases, several aspects of the biology of vector-borne diseases amplify this form of heterogeneity. Here, we review several aspects of this biology, highlighting seven distinct ways in which the biology of vector-borne diseases impacts understanding spatial heterogeneity in disease incidence. Whereas traditional methods place emphasis on spatial regression and other forms of statistical analysis of empirical data, the goal here is to offer a perspective on potential pitfalls of analyses that take data at face value and do not acknowledge the complex, nonlinear, and dynamic relationships between spatial patterns of disease incidence and spatial heterogeneity in transmission.
Niclas Jonzén, Endre Knudsen, Robert D. Holt, and Bernt‐Erik Sæther
- Published in print:
- 2011
- Published Online:
- December 2013
- ISBN:
- 9780199568994
- eISBN:
- 9780191774676
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199568994.003.0007
- Subject:
- Biology, Animal Biology
Animal movement is a general strategy for dealing with environmental variability, but takes on a variety of forms according to life history constraints and environmental covariates. This chapter ...
More
Animal movement is a general strategy for dealing with environmental variability, but takes on a variety of forms according to life history constraints and environmental covariates. This chapter contrasts migration with less regular nomadic movements, and invokes the niche concept for linking the diversity of movement patterns to the resource environment and the mechanisms of movement ecology. The statistical properties of the resource environment are key to understanding the merits of movement strategies in different environments, and particular emphasis is put on dimensions and scales of resource variability and predictability in space and time. While migration is frequently seen as an adaptation to avoiding severe conditions and exploiting predictable spatiotemporal variation in resource abundance, nomadism can be seen as an adaptation to variability and unpredictability rather than severity. An exploratory exposition illustrates how analysis of space-time data on resources can be helpful for explaining diversity of movement patterns.Less
Animal movement is a general strategy for dealing with environmental variability, but takes on a variety of forms according to life history constraints and environmental covariates. This chapter contrasts migration with less regular nomadic movements, and invokes the niche concept for linking the diversity of movement patterns to the resource environment and the mechanisms of movement ecology. The statistical properties of the resource environment are key to understanding the merits of movement strategies in different environments, and particular emphasis is put on dimensions and scales of resource variability and predictability in space and time. While migration is frequently seen as an adaptation to avoiding severe conditions and exploiting predictable spatiotemporal variation in resource abundance, nomadism can be seen as an adaptation to variability and unpredictability rather than severity. An exploratory exposition illustrates how analysis of space-time data on resources can be helpful for explaining diversity of movement patterns.
E.J. Milner-Gulland, John M. Fryxell, and Anthony R.E. Sinclair (eds)
- Published in print:
- 2011
- Published Online:
- December 2013
- ISBN:
- 9780199568994
- eISBN:
- 9780191774676
- Item type:
- book
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:oso/9780199568994.001.0001
- Subject:
- Biology, Animal Biology
This book takes a comparative, integrated view of migration, linking evolution with ecology and management, theory with empirical research, and embracing all the major migratory taxa (including ...
More
This book takes a comparative, integrated view of migration, linking evolution with ecology and management, theory with empirical research, and embracing all the major migratory taxa (including humans). The scope extends beyond the target organism to consider the ecosystem-level dynamics of migration. Rather than simply reviewing the field of migration as it stands today, the book highlights the lacunae in our knowledge and understanding. The emphasis is on exciting new research avenues that are now opening up, whether because of advances in our understanding of migration as a biological phenomenon or through the availability of a range of new technologies. Broad themes that emerge include smoothly integrating migration into the broad spectrum of movement behaviour; the need for a comparative and cross-taxonomic approach that considers migration at a range of temporal and spatial scales; and examination of the key roles of resource uncertainty and spatial heterogeneity in driving migratory behaviour. The chapters identify the potential for new tools to revolutionise the study of migration, including satellite-tracking technology, genomics and modelling – all of which are linked to increasing computing power. There is a current dearth of hypothesis-driven studies that fully integrate theory and empirical analyses, and a taxonomic bias towards birds in much migration research; both of these issues need to be resolved if we are to progress. We are on the verge of a breakthrough in migration research, which is crucial given the multiple threats that face the conservation of migration as a phenomenon, including climate change.Less
This book takes a comparative, integrated view of migration, linking evolution with ecology and management, theory with empirical research, and embracing all the major migratory taxa (including humans). The scope extends beyond the target organism to consider the ecosystem-level dynamics of migration. Rather than simply reviewing the field of migration as it stands today, the book highlights the lacunae in our knowledge and understanding. The emphasis is on exciting new research avenues that are now opening up, whether because of advances in our understanding of migration as a biological phenomenon or through the availability of a range of new technologies. Broad themes that emerge include smoothly integrating migration into the broad spectrum of movement behaviour; the need for a comparative and cross-taxonomic approach that considers migration at a range of temporal and spatial scales; and examination of the key roles of resource uncertainty and spatial heterogeneity in driving migratory behaviour. The chapters identify the potential for new tools to revolutionise the study of migration, including satellite-tracking technology, genomics and modelling – all of which are linked to increasing computing power. There is a current dearth of hypothesis-driven studies that fully integrate theory and empirical analyses, and a taxonomic bias towards birds in much migration research; both of these issues need to be resolved if we are to progress. We are on the verge of a breakthrough in migration research, which is crucial given the multiple threats that face the conservation of migration as a phenomenon, including climate change.
Roger Arditi and Lev R. Ginzburg
- Published in print:
- 2012
- Published Online:
- May 2015
- ISBN:
- 9780199913831
- eISBN:
- 9780190267902
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/acprof:osobl/9780199913831.003.0005
- Subject:
- Biology, Ecology
This chapter focuses on mechanistic theoretical approaches to explain the emergence of ratio dependence at a global scale from various behavioral models of species interaction. It explains how ...
More
This chapter focuses on mechanistic theoretical approaches to explain the emergence of ratio dependence at a global scale from various behavioral models of species interaction. It explains how refuges and spatial heterogeneity as well as forms of temporal and biological heterogeneities can lead to a ratio-dependent functional response. It provides a two-patch model that shows by what method donor control can emerge from being a prey refuge and being subject to intense predation. It also discusses how ratio dependence emerges in realistic models of predator-prey interactions where spatial distribution of both the predator and prey is explicitly followed. It highlights application of these models to the explanation of successful biological control of insect pests.Less
This chapter focuses on mechanistic theoretical approaches to explain the emergence of ratio dependence at a global scale from various behavioral models of species interaction. It explains how refuges and spatial heterogeneity as well as forms of temporal and biological heterogeneities can lead to a ratio-dependent functional response. It provides a two-patch model that shows by what method donor control can emerge from being a prey refuge and being subject to intense predation. It also discusses how ratio dependence emerges in realistic models of predator-prey interactions where spatial distribution of both the predator and prey is explicitly followed. It highlights application of these models to the explanation of successful biological control of insect pests.
John C. Callaway and V. Thomas Parker
- Published in print:
- 2012
- Published Online:
- January 2013
- ISBN:
- 9780520274297
- eISBN:
- 9780520954014
- Item type:
- chapter
- Publisher:
- University of California Press
- DOI:
- 10.1525/california/9780520274297.003.0018
- Subject:
- Biology, Ecology
Approaches for tidal-marsh restoration in San Francisco Bay and Delta continue to evolve, with a focus on promoting the natural development of restored marshes. Allowing for natural marsh development ...
More
Approaches for tidal-marsh restoration in San Francisco Bay and Delta continue to evolve, with a focus on promoting the natural development of restored marshes. Allowing for natural marsh development enhances the physical and biological heterogeneity of restored marshes, including tidal-channel formation. The scope of restoration efforts within the bay and delta has increased substantially over the last few decades, with large-scale, regional efforts replacing smaller-scale, mitigation-based restoration. There has also been a growing focus on the restoration of brackish and freshwater tidal marshes, rather than just salt-marsh restoration. Finally, climate change has become a major consideration for current and future bay and delta restoration; major restoration concerns for climate change include evaluating its impact on marsh migration and connectivity, carbon sequestration, and invasive species.Less
Approaches for tidal-marsh restoration in San Francisco Bay and Delta continue to evolve, with a focus on promoting the natural development of restored marshes. Allowing for natural marsh development enhances the physical and biological heterogeneity of restored marshes, including tidal-channel formation. The scope of restoration efforts within the bay and delta has increased substantially over the last few decades, with large-scale, regional efforts replacing smaller-scale, mitigation-based restoration. There has also been a growing focus on the restoration of brackish and freshwater tidal marshes, rather than just salt-marsh restoration. Finally, climate change has become a major consideration for current and future bay and delta restoration; major restoration concerns for climate change include evaluating its impact on marsh migration and connectivity, carbon sequestration, and invasive species.
David C. Culver and Tanja Pipan
- Published in print:
- 2019
- Published Online:
- June 2019
- ISBN:
- 9780198820765
- eISBN:
- 9780191860485
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/oso/9780198820765.003.0008
- Subject:
- Biology, Ecology, Biodiversity / Conservation Biology
Globally, for troglobionts, southern Europe, especially the Dinaric karst, and the Canary Islands are regions of high richness. For stygobionts, southern Europe, especially the Dinaric karst, is a ...
More
Globally, for troglobionts, southern Europe, especially the Dinaric karst, and the Canary Islands are regions of high richness. For stygobionts, southern Europe, especially the Dinaric karst, is a hotspot. Other sites are typically chemoautotrophic and/or phreatic. In Europe and North America, there appears to be a ridge of high troglobiotic and stygobiotic diversity in southern Europe and the southeast United States that corresponds to an area of long-term high surface productivity. In Europe, local diversity is a small component of regional stygobiotic diversity and the importance of spatial heterogeneity, historical climate stability, and productivity are both scale and spatially dependent. Habitat availability seems especially important at smaller scales. The analogy with islands in ecological time is most appropriate at scales smaller than caves, such as seeps or epikarst drips, and the analogy with caves in evolutionary time is more appropriate at larger scales, such as karst basins or contiguous karst areas.Less
Globally, for troglobionts, southern Europe, especially the Dinaric karst, and the Canary Islands are regions of high richness. For stygobionts, southern Europe, especially the Dinaric karst, is a hotspot. Other sites are typically chemoautotrophic and/or phreatic. In Europe and North America, there appears to be a ridge of high troglobiotic and stygobiotic diversity in southern Europe and the southeast United States that corresponds to an area of long-term high surface productivity. In Europe, local diversity is a small component of regional stygobiotic diversity and the importance of spatial heterogeneity, historical climate stability, and productivity are both scale and spatially dependent. Habitat availability seems especially important at smaller scales. The analogy with islands in ecological time is most appropriate at scales smaller than caves, such as seeps or epikarst drips, and the analogy with caves in evolutionary time is more appropriate at larger scales, such as karst basins or contiguous karst areas.
John M. Drake, Krisztian Magori, Kevin Knoblich, Sarah E. Bowden, and Waheed I. Bajwa
- Published in print:
- 2020
- Published Online:
- February 2021
- ISBN:
- 9780198853244
- eISBN:
- 9780191887710
- Item type:
- chapter
- Publisher:
- Oxford University Press
- DOI:
- 10.1093/oso/9780198853244.003.0005
- Subject:
- Biology, Disease Ecology / Epidemiology, Ecology
The size of annual outbreaks in seasonally forced host-pathogen systems is poorly understood. We studied contributing factors to the six-fold observed variation in the number of human cases of West ...
More
The size of annual outbreaks in seasonally forced host-pathogen systems is poorly understood. We studied contributing factors to the six-fold observed variation in the number of human cases of West Nile virus in New York City in the years 2000–2008. Sampling error and intrinsic noise (demographic stochasticity) explain roughly half of the observed variation. To investigate the remaining sources of variation, we estimated the monthly force of infection from data on the distribution and abundance of mosquitoes, virus prevalence, vector competence, and mammal biting rate at two spatial scales. At both scales, the West Nile virus force of infection was remarkably consistent from year to year. We propose that fine scale spatial heterogeneity is the key to understanding the epidemiology of West Nile virus in New York City.Less
The size of annual outbreaks in seasonally forced host-pathogen systems is poorly understood. We studied contributing factors to the six-fold observed variation in the number of human cases of West Nile virus in New York City in the years 2000–2008. Sampling error and intrinsic noise (demographic stochasticity) explain roughly half of the observed variation. To investigate the remaining sources of variation, we estimated the monthly force of infection from data on the distribution and abundance of mosquitoes, virus prevalence, vector competence, and mammal biting rate at two spatial scales. At both scales, the West Nile virus force of infection was remarkably consistent from year to year. We propose that fine scale spatial heterogeneity is the key to understanding the epidemiology of West Nile virus in New York City.