James Grace, Ph.D.
Wetland and Aquatic Research Center
700 Cajundome Blvd
Lafayette, LA 70506
Ph.D., Michigan State University
M.S., Clemson University
B.S., Biology, Presbyterian College
2015 - present Senior Research Scientist. U.S. Geological Survey, ST
2002 - 2014 Senior Research Ecologist, U.S. Geological Survey, GS-15
1993 - present Adjunct Professor, Department of Biology, University of Louisiana
2002 - present Affiliate Faculty, School of Renewable Natural Resources, LSU
1992 - 2002 Research Ecologist, U.S. Geological Survey, Biological Division
1990 - 1993 Professor, Department of Botany, Louisiana State University
1985 - 1990 Associate Professor, Department of Botany, Louisiana State Univ.
1989 Visiting Professor, Louisiana Universities Marine Consortium
1986 Visiting Scientist, Div. Wildlife, CSIRO, Darwin, Australia
1980‑1985 Assistant Professor, Dept. Botany and Microbiology, Univ. Arkansas summer
1980 Assistant Professor, Kellogg Biological Station, Michigan State Univ.
After graduate school, he held faculty positions at the University of Arkansas and Louisiana State University, where he reached the level of Full Professor. He currently holds an Adjunct Professorship in Biology at the University of Louisiana in Lafayette. In 2000, he received the millennium Meritorious Research Award from the Society of Wetland Scientists and in 2003 received the National Science Excellence Award from the U.S. Geological Survey. He was selected to be a Fellow of the Ecological Society of America and promoted to the Senior Scientist ranks in 2014. He has published over 180 papers and reports, including 3 books, one on competitive interactions, one on community analysis, and one on structural equation modeling.
Latest news releases related to our work (last 5 yrs) can be found at:
Elected Fellow of the Ecological Society of America (2014): http://www.usgs.gov/newsroom/article.asp?ID=3966
The Great Productivity-Diversity Debate: http://1560811.mediaspace.kaltura.com/media/James+Grace+pt+1/0_yy2jc1c3/...
Recommended Reading by Faculty of 1000 (2014): http://f1000.com/prime/717961256?bd=1
News Coverage (2013): http://www.nola.com/environment/index.ssf/2013/04/louisiana_seafood_heal...
USGS News Releases (2013): http://www.usgs.gov/newsroom/article.asp?ID=3544#.UVr1J7KPW8A
Science Perspectives piece (2011): http://www.sciencemag.org/content/333/6050/1709.full
National Science Foundation press release (2011): http://www.nsf.gov/news/news_summ.jsp?cntn_id=121691&org=DEB&from=news
USGS News Release (2010): http://www.usgs.gov/newsroom/article.asp?ID=2619
Conservation Maven (2010): http://www.conservationmaven.com/frontpage/predicting-the-performance-of...
USGS Genetics Program News Pick (2010): http://biology.usgs.gov/genetics_genomics/spotlight_2010.html
For more news and information, search 'Jim Grace USGS'. Additional information in publications can be found at my Google Scholar Profile: http://scholar.google.com/citations?user=53SGwowAAAAJ&hl=en&oi=ao
Training website for structural equation modeling: http://www.nwrc.usgs.gov/SEM
Science and Products
USGS scientists have been involved for a number of years in the development and use of Structural Equation Modeling (SEM). This methodology represents an approach to statistical modeling that focuses on the study of complex cause-effect hypotheses about the mechanisms operating in systems. SEM is increasingly used in ecological and environmental studies and this site seeks to provide educational materials related to that enterprise. This site serves up tutorials, exercises, and examples designed to help researchers learn and apply SEM. Please click on the “Science” tab to learn more.
Using structural equation modeling to link human activities to wetland ecological integrity
The integrity of wetlands is of global concern. A common approach to evaluating ecological integrity involves bioassessment procedures that quantify the degree to which communities deviate from historical norms. While helpful, bioassessment provides little information about how altered conditions connect to community response. More detailed information is needed for conservation and restoration...Schweiger, E. William; Grace, James B.; Cooper, David; Bobowski, Ben; Britten, Mike
Does urban sprawl hold down upward mobility?
Contrary to the general perception, the United States has a much more class-bound society than other wealthy countries. The chance of upward mobility for Americans is just half that of the citizens of the Denmark and many other European countries. In addition to other influences, the built environment may contribute to the low rate of upward mobility in the U.S. This study tests the relationship...Ewing, R.; Hamidi, Shima; Grace, James B.; Wei, Y.
Disentangling vegetation diversity from climate–energy and habitat heterogeneity for explaining animal geographic patterns
Broad-scale animal diversity patterns have been traditionally explained by hypotheses focused on climate–energy and habitat heterogeneity, without considering the direct influence of vegetation structure and composition. However, integrating these factors when considering plant–animal correlates still poses a major challenge because plant communities are controlled by abiotic factors that may, at...Jimenez-Alfaro, Borja; Chytry, Milan; Mucina, Ladislav; Grace, James B.; Rejmanek, Marcel
Comment on "Worldwide evidence of a unimodal relationship between productivity and plant species richness"
Fraser et al. (Reports, 17 July 2015, p. 302) report a unimodal relationship between productivity and species richness at regional and global scales, which they contrast with the results of Adler et al. (Reports, 23 September 2011, p. 1750). However, both data sets, when analyzed correctly, show clearly and consistently that productivity is a poor predictor of local species richness.Tredennick, Andrew T; Adler, Peter B.; Grace, James B.; Harpole, W Stanley; Borer, Elizabeth T.; Seabloom, Eric W.; Anderson, T. Michael; Bakker, Jonathan D.; Biederman, Lori A.; Brown, Cynthia S.; Buckley, Yvonne M.; Chu, Cheng-Jin; Collins, Scott L.; Crawley, Michael J.; Fay, Philip A.; Firn, Jennifer; Gruner, Daniel S.; Hagenah, Nicole; Hautier, Yann; Hector, Andy; Hillebrand, Helmut; Kirkman, Kevin P.; Knops, Johannes M. H.; Laungani, Ramesh; Lind, Eric M.; MacDougall, Andrew S.; McCulley, Rebecca L.; Mitchell, Charles E.; Moore, Joslin L.; Morgan, John W.; Orrock, John L.; Peri, Pablo L.; Prober, Suzanne M.; Risch, Anita C.; Schuetz, Martin; Speziale, Karina L.; Standish, Rachel J.; Sullivan, Lauren L.; Wardle, Glenda M.; Williams, Ryan J.; Yang, Louie H.
Beyond just sea-level rise: Considering macroclimatic drivers within coastal wetland vulnerability assessments to climate change
Due to their position at the land-sea interface, coastal wetlands are vulnerable to many aspects of climate change. However, climate change vulnerability assessments for coastal wetlands generally focus solely on sea-level rise without considering the effects of other facets of climate change. Across the globe and in all ecosystems, macroclimatic drivers (e.g., temperature and rainfall regimes)...Osland, Michael J.; Enwright, Nicholas M.; Day, Richard H.; Gabler, Christopher A.; Stagg, Camille L.; Grace, James B.
Compact development and VMT: environmental determinism, self-selection, or some of both?
There is a long-running debate in the planning literature about the effects of the built environment on travel behavior and the degree to which apparent effects are due to the tendency of households to self-select into neighborhoods that reinforce their travel preferences. Those who want to walk will choose walkable neighborhoods, and those who want to use transit will choose transit-served...Ewing, Reid; Hamidi, Shima; Grace, James B.
Urban sprawl as a risk factor in motor vehicle crashes
A decade ago, compactness/sprawl indices were developed for metropolitan areas and counties which have been widely used in health and other research. In this study, we first update the original county index to 2010, then develop a refined index that accounts for more relevant factors, and finally seek to test the relationship between sprawl and traffic crash rates using structural equation...Ewing, Reid; Hamidi, Shima; Grace, James B.
Taking a systems approach to ecological systems
Increasingly, there is interest in a systems-level understanding of ecological problems, which requires the evaluation of more complex, causal hypotheses. In this issue of the Journal of Vegetation Science, Soliveres et al. use structural equation modeling to test a causal network hypothesis about how tree canopies affect understorey communities. Historical analysis suggests structural equation...Grace, James B.
Landscape structure affects specialists but not generalists in naturally fragmented grasslands
Understanding how biotic communities respond to landscape spatial structure is critically important for conservation management as natural landscapes become increasingly fragmented. However, empirical studies of the effects of spatial structure on plant species richness have found inconsistent results, suggesting that more comprehensive approaches are needed. In this study, we asked how landscape...Miller, Jesse E.D.; Damschen, Ellen Ingman; Harrison, Susan P.; Grace, James B.
Does natural variation in diversity affect biotic resistance?
Theories linking diversity to ecosystem function have been challenged by the widespread observation of more exotic species in more diverse native communities. Few studies have addressed the key underlying process by dissecting how community diversity is shaped by the same environmental gradients that determine biotic and abiotic resistance to new invaders.Harrison, Susan; Cornell, Howard; Grace, James B.
From patterns to causal understanding: Structural equation modeling (SEM) in soil ecology
In this perspectives paper we highlight a heretofore underused statistical method in soil ecological research, structural equation modeling (SEM). SEM is commonly used in the general ecological literature to develop causal understanding from observational data, but has been more slowly adopted by soil ecologists.Eisenhauer, Nico; Powell, Jeff R; Grace, James B.; Bowker, Matthew A.
Do shrubs reduce the adverse effects of grazing on soil properties?
Increases in the density of woody plants are a global phenomenon in drylands, and large aggregations of shrubs, in particular, are regarded as being indicative of dysfunctional ecosystems. There is increasing evidence that overgrazing by livestock reduces ecosystem functions in shrublands, but that shrubs may buffer the negative effects of increasing grazing. We examined changes in water...Eldridge, David J.; Beecham, Genevieve; Grace, James B.
Researchers have found clear evidence that biological communities rich in species are substantially healthier and more productive than those depleted of species.