I am currently involved in three general areas of research:

MISSISSIPPI RIVER DELTA

First, and foremost, I am working on the wetlands at the mouth of the Mississippi River.  A large part of the field emphasis has been on plant colonization and succession on new and old mudflats that are a part of a complex of land owned and operated by the U.S. Fish & Wildlife Service.  For many years now (since 1984), I have collected annual biomass data during August, the time of greatest plant abundance.  Typical for wetlands, allogenic forces (from outside the ecosystem) drive the system.  To put it bluntly, Mississippi River 'rules' in this area located outside the artificial levee system!  I have discovered that the amount and quality of plant biomass varies a great deal from year to year and that the River has much to do with this.

Additionally, I have been collaborating with scientists from the United States Geological Survey on a project of great interest to this State of Louisiana – a place of incredible rate of wetland loss.  On permanent study sites, on the mudflats at the mouth of the Mississippi, we have been tracking subsidence and accretion rates in several different habitats to assess impacts of the wetland plants on these processes.  Both this and the biomass project should continue for some time to come.

I have also been studying the plant, Phragmites australis, which grows into huge monospecific stands in the peripheral wetlands of the Mississippi River delta.  Some years back, I hooked up with a colleague in Biology (Don Hauber), to study this plant's population ecology in the delta.  Just recently, Craig Hood in Biology, has joined us as the statistician.  After a short hiatus on this work, I am about to begin a follow-up study to look at the growth rate of the clones of Phragmites to see if there is a difference according to genotypes across the delta wetlands.   In other parts of the world, this species is quite invasive and is altering the quality of many wetlands.  We believe the plant has been in the Mississippi River delta for at least 100 years, but only in the past 50 has it become a dominant.
 

BOTTOMLAND HARDWOOD FORESTS

I have also been studying the remnant forests of this region of southeastern Louisiana.  Because forest land is so valuable for development, nearly all of the original areas that supported bottomland forests have been converted into either municipalities or agricultural areas.  The focus of this research has been to simply document the quantity and quality of woody species at the several regional sites.  Currently, only one major forested area still has yet to be adequately described.  The 'English Turn' forest, is a particularly significant site because of its size, community diversity, and age of some of the stands of trees.   Several years back, an undergraduate student at Loyola University completed an Honors project on the English Turn forest.  I am eager to complete the study by adding to the student's data set.
    Also, and more ecologically significant, I want to look at levee forest community change parallel to stream flow.  Studies to date on bottomland hardwood forests have documented change away from (perpendicular to) stream flow.  I have located two rather intact forest strips growing on ancient levees outside the man-made flood protection system of this region.  The elevation of these forest strips gradually (over kms) grades to the elevation supporting a herbaceous marsh community.  I believe that there should be a change in forest species diversity, dominance, and age structure over this distance of kms.
    Just recently, I have begun a collaboration with Jeff Chambers (Tulane University) to look at forest productivity across a flood gradient within the lower Pearl River basin.  This project could develop into a longterm and major effort that has considerable funding possibilities from a remote sensing and climate change angle.  The overall goal of this initial project is to characterize variability in net primary productivity (NPP) components along biotic and abiotic gradients. These plots will also be utilized to test a satellite remote sensing hyperspectral method of quantifying canopy nitrogen content, and regional variability in NPP.  The remote sensing data will also be useful for quantifying regional variability in forest tree species community composition.  These data will serve as the basis for characterizing the carbon balance of the Pearl River WMA.
 

DRY TROPICAL FORESTS

During my latter days at Tulane University, I was a part of a group inventorying the large woody plants (principally trees) of the northern Yucatan Peninsula, Mexico. Tulane has had a long connection with the Yucatan, primarily associated with their Mayan studies.  In 1982, I initiated a study to document woody plants of the oldest forests of the northern Yucatan and to compare the vegetation of forests to that of Mayan Ruin sites.   The Peninsula is primarily of dry tropical forest type.  Some of the data analysis for that work was put on hold until very recently.  Over the past couple of years, I have revisited the massive data set, and along with Craig Hood in Biology, began to look at the data using several sophisticated multivariate techniques to find patterns in the vegetation related to abiotic features (soil type, climate) collected from the forests.  The first of this collaborative effort has just recently been published.  We hope to do more.