SEDIMENT DISTRIBUTION ANALYSIS USING GIS FOR THE BAHIA GRANDE WETLAND RESTORATION, SOUTH TEXAS

Baseline sediment distribution data was collected and analyzed for the entire Bahia Grande Wetland near Brownsville, Texas. These data were analyzed in order to determine the overall distribution within the system utilizing GIS (Geographic Information Systems). Grain size analysis (Folk, 1980), were conducted on 25 different shallow sediment cores, and sampled on a random grid.

The Bahia Grande Wetland complex is part of the Laguna Atascosa National Wildlife Refuge. It is located on the southern tip of Texas 15 miles from the Lower Laguna Madre. The Bahia Grande wetlands were in communication with Lower Laguna Madre prior to the dredging of the Brownsville ship channel 74 yrs. ago. The restoration of the wetland complex was started as an effort to alleviate the particulate matter pollution derived by the playa lake system

Recent exploration for gas in South Texas has disrupted the sediments and the algal mats within Bahia Grande. Distortion of the system equilibrium may make it difficult to obtain a true sense of distribution next sampling cycle. Future work involves determining conditions of the depositional environment and characterizing paleo-habitats, based on data obtained.