James Grace, Ph.D. (Former Employee)
Science and Products
Filter Total Items: 187
A general theory of multimetric indices and their properties A general theory of multimetric indices and their properties
1. Stewardship of biological and ecological resources requires the ability to make integrative assessments of ecological integrity. One of the emerging methods for making such integrative assessments is multimetric indices (MMIs). These indices synthesize data, often from multiple levels of biological organization, with the goal of deriving a single index that reflects the overall...
Authors
Donald Schoolmaster, James Grace, E. Schweiger
An algorithmic and information-theoretic approach to multimetric index construction An algorithmic and information-theoretic approach to multimetric index construction
The use of multimetric indices (MMIs), such as the widely used index of biological integrity (IBI), to measure, track, summarize and infer the overall impact of human disturbance on biological communities has been steadily growing in recent years. Initially, MMIs were developed for aquatic communities using pre-selected biological metrics as indicators of system integrity. As interest in...
Authors
Donald Schoolmaster, James Grace, E. Schweiger, Glenn Guntenspergen, Brian Mitchell, Kathryn Miller, Amanda Little
Guidelines for a graph-theoretic implementation of structural equation modeling Guidelines for a graph-theoretic implementation of structural equation modeling
Structural equation modeling (SEM) is increasingly being chosen by researchers as a framework for gaining scientific insights from the quantitative analyses of data. New ideas and methods emerging from the study of causality, influences from the field of graphical modeling, and advances in statistics are expanding the rigor, capability, and even purpose of SEM. Guidelines for...
Authors
James Grace, Donald Schoolmaster, Glenn Guntenspergen, Amanda Little, Brian Mitchell, Kathryn Miller, E. Schweiger
Biodiversity loss and its impact on humanity Biodiversity loss and its impact on humanity
The most unique feature of Earth is the existence of life, and the most extraordinary feature of life is its diversity. Approximately 9 million types of plants, animals, protists and fungi inhabit the Earth. So, too, do 7 billion people. Two decades ago, at the first Earth Summit, the vast majority of the world's nations declared that human actions were dismantling the Earth's ecosystems
Authors
Bradley J. Cardinale, J. Duffy, Andrew Gonzalez, David Hooper, Charles Perrings, Patrick Venail, Anita Narwani, Georgina Mace, David Tilman, David Wardle, Ann Kinzig, Gretchen Daily, Michel Loreau, James Grace, Anne Larigauderie, Diane Srivastava, Shahid Naeem
Response to comments on "Productivity is a poor predictor of plant species richness" Response to comments on "Productivity is a poor predictor of plant species richness"
Pan et al. claim that our results actually support a strong linear positive relationship between productivity and richness, whereas Fridley et al. contend that the data support a strong humped relationship. These responses illustrate how preoccupation with bivariate patterns distracts from a deeper understanding of the multivariate mechanisms that control these important ecosystem...
Authors
James Grace, Peter Adler, Eric Seabloom, Elizabeth Borer, Helmut Hillebrand, Yann Hautier, Andy Hector, W. Stanley Harpole, Lydia O’Halloran, T. Michael Anderson, Jonathan Bakker, Cynthia Brown, Yvonne Buckley, Scott L. Collins, Kathryn Cottingham, Michael Crawley, Ellen Damschen, Kendi Davies, Nicole DeCrappeo, Philip Fay, Jennifer Firn, Daniel S. Gruner, Nicole Hagenah, Virginia Jin, Kevin Kirkman, Johannes Knops, Kimberly La Pierre, John Lambrinos, Brett Melbourne, Charles E. Mitchell, Joslin Moore, John Morgan, John L. Orrock, Suzanne Prover, Carly Stevens, Peter Wragg, Louie Yang
Effects of prescribed burning on marsh-elevation change and the risk of wetland loss Effects of prescribed burning on marsh-elevation change and the risk of wetland loss
Marsh-elevation change is the net effect of biophysical processes controlling inputs versus losses of soil volume. In many marshes, accumulation of organic matter is an important contributor to soil volume and vertical land building. In this study, we examined how prescribed burning, a common marsh-management practice, may affect elevation dynamics in the McFaddin National Wildlife...
Authors
Karen McKee, James Grace
Structural equation modeling and the analysis of long-term monitoring data Structural equation modeling and the analysis of long-term monitoring data
No abstract available.
Authors
James Grace, Jon Keeley, Darren J. Johnson, Kenneth Bollen
Productivity is a poor predictor of plant species richness Productivity is a poor predictor of plant species richness
For more than 30 years, the relationship between net primary productivity and species richness has generated intense debate in ecology about the processes regulating local diversity. The original view, which is still widely accepted, holds that the relationship is hump-shaped, with richness first rising and then declining with increasing productivity. Although recent meta-analyses...
Authors
Peter Adler, Eric Seabloom, Elizabeth Borer, Helmut Hillebrand, Yann Hautier, Andy Hector, W. Stanley Harpole, Lydia O’Halloran, James Grace, T. Michael Anderson, Jonathan Bakker, Lori Biederman, Cynthia Brown, Yvonne Buckley, Laura Calabrese, Cheng-Jin Chu, Elsa E. Cleland, Scott L. Collins, Kathryn Cottingham, Michael Crawley, Ellen Damschen, Kendi Davies, Nicole DeCrappeo, Philip Fay, Jennifer Firn, Paul Frater, Eve Gasarch, Daneil Gruner, Nicole Hagenah, Janneke Lambers, Hope Humphries, Virginia Jin, Adam Kay, Kevin Kirkman, Julia Klein, Johannes Knops, Kimberly La Pierre, John Lambrinos, Wei Li, Andrew MacDougall, Rebecca McCulley, Brett Melbourne, Charles E. Mitchell, Joslin Moore, John Morgan, Brent Mortensen, John L. Orrock, Suzanne Prober, David Pyke, Anita C. Risch, Martin Schuetz, Melinda D. Smith, Carly Stevens, Lauren Sullivan, Gang Wang, Peter Wragg, Justin Wright, Louie Yang
Local richness along gradients in the Siskiyou herb flora: R. H. Whittaker revisited Local richness along gradients in the Siskiyou herb flora: R. H. Whittaker revisited
In his classic study in the Siskiyou Mountains (Oregon, USA), one of the most botanically rich forested regions in North America, R. H. Whittaker (1960) foreshadowed many modern ideas on the multivariate control of local species richness along environmental gradients related to productivity. Using a structural equation model to analyze his data, which were never previously statistically...
Authors
James Grace, Susan Harrison, Ellen Damschen
Landscape-scale analyses suggest both nutrient and antipredator advantages to Serengeti herbivore hotspots Landscape-scale analyses suggest both nutrient and antipredator advantages to Serengeti herbivore hotspots
Mechanistic explanations of herbivore spatial distribution have focused largely on either resource‐related (bottom‐up) or predation‐related (top‐down) factors. We studied direct and indirect influences on the spatial distributions of Serengeti herbivore hotspots, defined as temporally stable areas inhabited by mixed herds of resident grazers. Remote sensing and variation in landscape...
Authors
T. Michael Anderson, J. Hopcraft, Stephanie Eby, Mark Ritchie, James Grace, Han Olff
Predicting performance for ecological restoration: A case study using Spartina altemiflora Predicting performance for ecological restoration: A case study using Spartina altemiflora
The success of population-based ecological restoration relies on the growth and reproductive performance of selected donor materials, whether consisting of whole plants or seed. Accurately predicting performance requires an understanding of a variety of underlying processes, particularly gene flow and selection, which can be measured, at least in part, using surrogates such as neutral...
Authors
S.E. Travis, J.B. Grace
On the specification of structural equation models for ecological systems On the specification of structural equation models for ecological systems
The use of structural equation modeling (SEM) is often motivated by its utility for investigating complex networks of relationships, but also because of its promise as a means of representing theoretical concepts using latent variables. In this paper, we discuss characteristics of ecological theory and some of the challenges for proper specification of theoretical ideas in structural...
Authors
James Grace, T. Michael Anderson, Han Olff, S.M. Scheiner
Science and Products
Filter Total Items: 187
A general theory of multimetric indices and their properties A general theory of multimetric indices and their properties
1. Stewardship of biological and ecological resources requires the ability to make integrative assessments of ecological integrity. One of the emerging methods for making such integrative assessments is multimetric indices (MMIs). These indices synthesize data, often from multiple levels of biological organization, with the goal of deriving a single index that reflects the overall...
Authors
Donald Schoolmaster, James Grace, E. Schweiger
An algorithmic and information-theoretic approach to multimetric index construction An algorithmic and information-theoretic approach to multimetric index construction
The use of multimetric indices (MMIs), such as the widely used index of biological integrity (IBI), to measure, track, summarize and infer the overall impact of human disturbance on biological communities has been steadily growing in recent years. Initially, MMIs were developed for aquatic communities using pre-selected biological metrics as indicators of system integrity. As interest in...
Authors
Donald Schoolmaster, James Grace, E. Schweiger, Glenn Guntenspergen, Brian Mitchell, Kathryn Miller, Amanda Little
Guidelines for a graph-theoretic implementation of structural equation modeling Guidelines for a graph-theoretic implementation of structural equation modeling
Structural equation modeling (SEM) is increasingly being chosen by researchers as a framework for gaining scientific insights from the quantitative analyses of data. New ideas and methods emerging from the study of causality, influences from the field of graphical modeling, and advances in statistics are expanding the rigor, capability, and even purpose of SEM. Guidelines for...
Authors
James Grace, Donald Schoolmaster, Glenn Guntenspergen, Amanda Little, Brian Mitchell, Kathryn Miller, E. Schweiger
Biodiversity loss and its impact on humanity Biodiversity loss and its impact on humanity
The most unique feature of Earth is the existence of life, and the most extraordinary feature of life is its diversity. Approximately 9 million types of plants, animals, protists and fungi inhabit the Earth. So, too, do 7 billion people. Two decades ago, at the first Earth Summit, the vast majority of the world's nations declared that human actions were dismantling the Earth's ecosystems
Authors
Bradley J. Cardinale, J. Duffy, Andrew Gonzalez, David Hooper, Charles Perrings, Patrick Venail, Anita Narwani, Georgina Mace, David Tilman, David Wardle, Ann Kinzig, Gretchen Daily, Michel Loreau, James Grace, Anne Larigauderie, Diane Srivastava, Shahid Naeem
Response to comments on "Productivity is a poor predictor of plant species richness" Response to comments on "Productivity is a poor predictor of plant species richness"
Pan et al. claim that our results actually support a strong linear positive relationship between productivity and richness, whereas Fridley et al. contend that the data support a strong humped relationship. These responses illustrate how preoccupation with bivariate patterns distracts from a deeper understanding of the multivariate mechanisms that control these important ecosystem...
Authors
James Grace, Peter Adler, Eric Seabloom, Elizabeth Borer, Helmut Hillebrand, Yann Hautier, Andy Hector, W. Stanley Harpole, Lydia O’Halloran, T. Michael Anderson, Jonathan Bakker, Cynthia Brown, Yvonne Buckley, Scott L. Collins, Kathryn Cottingham, Michael Crawley, Ellen Damschen, Kendi Davies, Nicole DeCrappeo, Philip Fay, Jennifer Firn, Daniel S. Gruner, Nicole Hagenah, Virginia Jin, Kevin Kirkman, Johannes Knops, Kimberly La Pierre, John Lambrinos, Brett Melbourne, Charles E. Mitchell, Joslin Moore, John Morgan, John L. Orrock, Suzanne Prover, Carly Stevens, Peter Wragg, Louie Yang
Effects of prescribed burning on marsh-elevation change and the risk of wetland loss Effects of prescribed burning on marsh-elevation change and the risk of wetland loss
Marsh-elevation change is the net effect of biophysical processes controlling inputs versus losses of soil volume. In many marshes, accumulation of organic matter is an important contributor to soil volume and vertical land building. In this study, we examined how prescribed burning, a common marsh-management practice, may affect elevation dynamics in the McFaddin National Wildlife...
Authors
Karen McKee, James Grace
Structural equation modeling and the analysis of long-term monitoring data Structural equation modeling and the analysis of long-term monitoring data
No abstract available.
Authors
James Grace, Jon Keeley, Darren J. Johnson, Kenneth Bollen
Productivity is a poor predictor of plant species richness Productivity is a poor predictor of plant species richness
For more than 30 years, the relationship between net primary productivity and species richness has generated intense debate in ecology about the processes regulating local diversity. The original view, which is still widely accepted, holds that the relationship is hump-shaped, with richness first rising and then declining with increasing productivity. Although recent meta-analyses...
Authors
Peter Adler, Eric Seabloom, Elizabeth Borer, Helmut Hillebrand, Yann Hautier, Andy Hector, W. Stanley Harpole, Lydia O’Halloran, James Grace, T. Michael Anderson, Jonathan Bakker, Lori Biederman, Cynthia Brown, Yvonne Buckley, Laura Calabrese, Cheng-Jin Chu, Elsa E. Cleland, Scott L. Collins, Kathryn Cottingham, Michael Crawley, Ellen Damschen, Kendi Davies, Nicole DeCrappeo, Philip Fay, Jennifer Firn, Paul Frater, Eve Gasarch, Daneil Gruner, Nicole Hagenah, Janneke Lambers, Hope Humphries, Virginia Jin, Adam Kay, Kevin Kirkman, Julia Klein, Johannes Knops, Kimberly La Pierre, John Lambrinos, Wei Li, Andrew MacDougall, Rebecca McCulley, Brett Melbourne, Charles E. Mitchell, Joslin Moore, John Morgan, Brent Mortensen, John L. Orrock, Suzanne Prober, David Pyke, Anita C. Risch, Martin Schuetz, Melinda D. Smith, Carly Stevens, Lauren Sullivan, Gang Wang, Peter Wragg, Justin Wright, Louie Yang
Local richness along gradients in the Siskiyou herb flora: R. H. Whittaker revisited Local richness along gradients in the Siskiyou herb flora: R. H. Whittaker revisited
In his classic study in the Siskiyou Mountains (Oregon, USA), one of the most botanically rich forested regions in North America, R. H. Whittaker (1960) foreshadowed many modern ideas on the multivariate control of local species richness along environmental gradients related to productivity. Using a structural equation model to analyze his data, which were never previously statistically...
Authors
James Grace, Susan Harrison, Ellen Damschen
Landscape-scale analyses suggest both nutrient and antipredator advantages to Serengeti herbivore hotspots Landscape-scale analyses suggest both nutrient and antipredator advantages to Serengeti herbivore hotspots
Mechanistic explanations of herbivore spatial distribution have focused largely on either resource‐related (bottom‐up) or predation‐related (top‐down) factors. We studied direct and indirect influences on the spatial distributions of Serengeti herbivore hotspots, defined as temporally stable areas inhabited by mixed herds of resident grazers. Remote sensing and variation in landscape...
Authors
T. Michael Anderson, J. Hopcraft, Stephanie Eby, Mark Ritchie, James Grace, Han Olff
Predicting performance for ecological restoration: A case study using Spartina altemiflora Predicting performance for ecological restoration: A case study using Spartina altemiflora
The success of population-based ecological restoration relies on the growth and reproductive performance of selected donor materials, whether consisting of whole plants or seed. Accurately predicting performance requires an understanding of a variety of underlying processes, particularly gene flow and selection, which can be measured, at least in part, using surrogates such as neutral...
Authors
S.E. Travis, J.B. Grace
On the specification of structural equation models for ecological systems On the specification of structural equation models for ecological systems
The use of structural equation modeling (SEM) is often motivated by its utility for investigating complex networks of relationships, but also because of its promise as a means of representing theoretical concepts using latent variables. In this paper, we discuss characteristics of ecological theory and some of the challenges for proper specification of theoretical ideas in structural...
Authors
James Grace, T. Michael Anderson, Han Olff, S.M. Scheiner