Restoring Biological Diversity to Wetlands of the Greater Manchac Region

Project Overview

A major conservation challenge this century will be maintaining (and restoring) biological diversity in the Earth’s living systems. Within this global context, our regional work over the past three years has had two driving questions:

(1) What are the patterns of biological diversity within wetland plant communities of the greater Manchac region?

(2) What are the environmental factors that control these patterns?

Our studies lie in three areas of expanding scale. They are to:

1. Investigate ecological factors such as herbivory, sedimentation, and fire that might control diversity and production in these oligohaline marshes in the Turtle Cove Experimental Marsh.

Studies include:

• Competition and Zonation in an Assemblage of Ten Species of Marsh Plants
  

• Filters Controlling the Species Pool of Coastal Marshes

• Effects of Disturbance and Fertility upon the Vegetation of a Louisiana Coastal Marsh: An Evaluation of Huston’s General Model of Diversity

• Seed Banks in Coastal Marshes

• A Classification of Plant Community Types in the Manchac Swamp

• Herbivore Communities of the Upper Lake Pontchartrain Basin, Southeast Louisiana

2. Expand diversity research to the landscape scale. We will identify the areas of highest plant diversity within the greater Manchac region, and explore the processes (e.g. seed dispersal during spring flooding, storage as buried seeds) that maintain the plant species pool. These are critical missing pieces of information for setting conservation priorities and managing the ecosystem.

3. Begin a geographical information system (GIS) database for the greater Manchac. This product will service the combined research, education and conservation community involved in this project. It will provide an evolving set of landscape scale “images” of ecological and historical features for the entire study area (roughly the area northeast of the Mississippi and west of the Lake Pontchartrain causeway). At first, this GIS database will focus on plant communities, but any other geo-referenced data (from abandoned towns to bird rookeries) can be added as the system grows. A short-term priority will be five maps, one depicting the ecological status of the region in the mid 1800’s, one showing current conditions and three depicting consequences of possible restoration scenarios (no action, modest action and major restoration).

P. Keddy