USGS - science for a changing world

USGS Professional Pages

Blank space
Search USGS Professionals Featured Profiles Blank space Frequently Asked Questions  |  About The USGS Professional Pages

James Grace

RESEARCH ECOLOGIST

Contact Info


Short Biography

Jim Grace obtained his B.S. in Biology from Presbyterian College in South Carolina, his M.S. from Clemson University, and his Ph.D. from Michigan State University. 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 has published over 160 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 can be found at:

 

Recommended Reading by Faculty of 1000: http://f1000.com/prime/717961256?bd=1  
Nature (2013): http://www.nature.com/news/world-governments-establish-biodiversity-panel-1.10505?WT.ec_id=NEWS-20120424  
New Coverage (2013): http://www.nola.com/environment/index.ssf/2013/04/louisiana_seafood_healthier_du.html 
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

Press (2010): http://www.examiner.com/liberal-in-national/study-climate-change-adversely-affects-low-elevation-mountain-vegetation

News (2010): http://www.climatecentral.org/breaking/blog/climate_in_context_a_60_year_glimpse_at_local_climate_change_affects

Conservation Maven (2010): http://www.conservationmaven.com/frontpage/predicting-the-performance-of-plant-restoration.html

USGS Genetics Program News Pick (2010): http://biology.usgs.gov/genetics_genomics/spotlight_2010.html

Nature Climate Change Research Highlights (2009): http://www.nature.com/climate/2009/0905/full/climate.2009.32.html

USGS Science Newsroom Pick (2009): http://www.nature.com/climate/2009/0905/full/climate.2009.32.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



Read Full Professional Summary

Download CV

Publications

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1





My USGS Science Strategy Areas

Understanding Ecosystems & Predicting Ecosystems Change

Ecological analysis and structural equations

Jim Grace - Ecology and society are moving from a historical emphasis on individual processes to a concern about entire systems. The complexity of the world in which we live, along with the increased level of our ambitions, now cause us to want to understand systems and predict, as much as we can, their behavior. Understanding systems requires approaches that permit both the discovery and extrapolation of system structure. Analytically, systems are often represented as networks of interacting elements, thus the business of studying systems can be approached using methods for studying causal networks.
 
One approach to studying causal networks is structural equation modeling (SEM). From an historical perspective, the SEM currently practiced can be called “Second Generation” SEM. The first phase of development, “First Generation SEM”, was based on the path analysis methodology developed by Sewell Wright. The “Second Generation” of SEM commenced with the LISREL synthesis in the early 1970’s and continues as the dominant form of application to the present.
 
We believe there is now a need for a “Third Generation” of SEM that is more fundamental, more flexible, and a more complete scientific system. A more fundamental approach would permit direct specification of SE models and the flexibility to customize their properties. Current SEM software takes the opposite approach, packaging complex routines into cryptic modules, with add-ons that seek to overcome the inherent limitations of a global covariance analysis. Regarding completeness as a scientific system, the practice of SEM has historically been an analysis framework that emphasizes discovering network structure and testing hypotheses about networks. Increasingly there is a need to extend our work to include prediction and forecasting.
 
In a new paper, we describe the implementation of next-generation SEM using a "Graph-Theoretic" approach. That paper is:
 
Grace, J.B., Schoolmaster, D.R. Jr., Guntenspergen, G.R., Little, A.M., Mitchell, B.R., Miller, K.M., and Schweiger, E.W. 2012. "Guidelines for a graph-theoretic implementation of structural equation modeling." Ecosphere
 
Work is well underway to develop an R package to automate the procedures described in this paper.
 
In addition to advancing methodology, major topics of current emphasis include:
 
Global Climate Change Effects – Projects in this theme include studies of the effects of sea level rise on coastal marshes, regional vegetation shifts in California, and the role of genomics in ecosystem adaptation.
 
Developing Integrative Measures of Ecosystem Health - Working with the National Park Service, we have been evaluating current methods for estimating biotic integrity.
 
Identifying the Linkages between Stressors and Forest Health in Eastern National Parks - This work, also in collaboration with the National Park Service, seeks to further the work of their Vital Signs program using SEM to develop hypotheses about how particular forces influence individual forest health metrics.
 
Other Applications – Perusing the papers listed under "Publications" provides information on other applications we have been involved with.

Contact Information

James Grace
700 Cajundome Blvd.
Lafayette, LA 70506
gracej@usgs.gov
337-266-8632
337-266-8592 - Fax
Back to top

Accessibility FOIA Privacy Policies and Notices

Take Pride in America logo USA.gov logo U.S. Department of the Interior | U.S. Geological Survey
URL: https://profile.usgs.gov/professional/mypage.php
Page Contact Information:Ask USGS
Page Last Modified: January 24 2013 17:21:51.
Version: 2.6