To accomplish this, we developed an ecosystem-based management approach, founded on a 

 sound data base and a conceptual framework which incorporated the principles of natural resource 

 management. Despite the need for more pre-wetland management environmental data collection 

 and analysis, Louisiana coastal management plans often lack a sufficient scientific baseline 

 characterization of the area in question. Hence, information is needed to determine whether 

 wetland management strategies actually achieve the goals for which they were designed. 



Much coastal wetland management in Louisiana has recently become synonymous with semi- 

 impoundment (Templet and Meyer-Arendt 1988), and much of Louisiana's coastal wetlands are 

 currently impounded or semi-impounded (Day et al. 1989) by water-control structures to slow land 

 loss and increase productivity in managed areas. There is, however, a lack of evidence and much 

 controversy about the effectiveness of such marsh management and there is evidence that 

 impoundment of wetlands may in some cases be exacerbating the geologic problems currently 

 associated with Louisiana's subsiding coastline (Day et al. 1989). Thus we attempted to develop 

 an ecological characterization which would lead to an adequate data base for management as well 

 as a monitoring plan to test management effectiveness. The specific objectives included (1) 

 establishing wetland management units within the area based on local hydrology, natural biological 

 and physical features, and previous studies, (2) conducting an intensive year-long environmental 

 data collection program to characterize the surface hydrology, salinity patterns, sedimentation rates, 

 soil characteristics, gross water movements, water budget, and emergent plant species distributions 

 to determine if saltwater intrusion, sediment starvation, and altered hydrology are problems in the 

 park, and (3) using the ecological characterization for the development of a management plan 

 aimed at preventing continued wetland degradation. 



DESCRIPTION OF STUDY AREA 



The park is a 5,160 ha area located in the central Barataria Basin (Figure 1). Elevations in the 

 park grade from greater than 1 m above sea level on a bottomland ridge to near sea level in fresh 

 and intermediate marshes. The soils include highly organic Holocene soil series such as Allemand, 

 Kenner, Lafitte, and Larose (Soil Conservation Service 1985). Vegetation includes various types 

 of lowland deciduous hardwoods and cypress-tupelo communities (White et al. 1983). Young 

 disturbed canal spoil banks support Salix nigra, Myrica cerifera, Iva frutescens, and Phragmites 

 australis {communis), in addition to an introduced species, Sapium sebiferum. Older spoil banks 

 (>50 years old) support species resembling those found on cheniers of coastal Louisiana (White 

 et al. 1983). Common trees are Taxodium distichum, Celtis laevigata, Quercus virginiana, 

 Liquidambar stryaciflua, Acer rubrum, Quercus nigra, and Salix nigra (White et al. 1983). The 

 intermediate marsh is characterized by Spartina patens, Phragmites australis, and a mix of freshwater 

 plants. The freshwater marsh is dominated by Sagittaria lancifolia, Panicum hemitonum, Polygonum 

 punctatumn, and Altemanthera philoxeroides. 



Hydrology of the Area 



Rainfall, evapotranspiration, tides, and wind are the primary forcing functions responsible for the 

 hydrologic patterns in central Barataria Basin freshwater swamps and marshes (Conner and Day 

 1987). The natural hydrology of the area included both overland flow from the natural levee 

 through the forests and marshes into Lakes Salvadore and Cataouatche, and streamflow through 

 Bayous des Families and Coquille. Prior to the completion of the artificial Mississippi River levee 

 system, riverine sediments were deposited in the Barataria Basin by overbank flow and crevasse 

 formation. At present, the major external sediment input to marsh and swamp areas is resuspended 

 bay bottom sediments (Baumann et al. 1984). 



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