An Ecological Characterization Study 



of the 



Chenier Plain Coastal Ecosystem 



of Louisiana and Texas 



6.0 INTRODUCTION 



An ecological system or ecosystem is a complex 

 of plants and animals interacting with one another 

 and with their habitat or physical environment. Man, 

 too, is an integral part of the ecosystem and his 

 actions and activities influence, and are influenced 

 by, other processes and components. Only when man 

 understands how ecosystems operate will he be able 

 to improve his management of natural resources 

 and guide developments generated by his social 

 and economic systems. 



An ecological characterization study describes 

 the important components and processes of an eco- 

 system and provides an understanding of their inter- 

 relationships by synthesizing and integrating exist- 

 ing physical, biological, and socioeconomic infor- 

 mation. The main purpose is to provide an informa- 

 tion base to aid in evaluating human impacts on 

 the ecosystem and to provide an ecological frame- 

 work for guiding resource management and coastal 

 planning. 



The Chenier Plain in southwestern Louisiana and 

 southeastern Texas is a relatively large coastal eco- 

 system created by 5,000 years of sediment deposition 

 from the Mississippi River. This ecosystem was selected 

 for study because of its biological diversity, valuable 

 fish and wildlife resources, and its proximity to actual 

 and proposed oil and gas production activities. 



The contents of the Chenier Plain Ecological 

 Characterization are organized into three volumes. 

 Volume I is a narrative report containing a descrip- 

 tion and analysis of climatic, geomorphic, and func- 

 tional processes that formed, or are changing, the 

 Chenier Plain ecosystem. Descriptions of the drainage 

 basins, habitats, and some of the most important 

 animal species are presented. 



Volume II (Appendixes), in five parts, generally 

 is a continuation of the elements of Volume I. Part 

 6.1 contains geological, hydrological, meterological, 

 chemical, biological, and socioeconomic data sources. 

 Part 6.2 describes socioeconomics, oil and gas pro- 

 duction, agricultural values, sport and commercial 

 fisheries, fur trapping, and waterborne transportation. 

 Part 6.3 gives biological information about primary 

 production, waterfowl, fishes, and a habitat/species 

 list. Part 6.4 contains data about water discharges, 

 phosphorus levels, and habitat changes. Literature 

 sources for the appendixes are listed in Part 6.5. 



Volume III (Atlas) consists of the following 

 eleven plates (maps): 



1. 



2. 

 3. 



5. 



6. 



Plates 1A and IB- Index Maps >s 



Plate 2— The Pleistocene Erosional Surface 

 Plates 3A and 3B-Chenier Plain Habitat 

 Groups 



Plates 4A and 4B-Chenier Plain Wetland 

 Habitats 



Plates 5A and 5B-Canals and Point Source 

 Discharges 



Plates 6A and 6B -Special Features (bird- 

 nesting colonies, archeological sites, refuges 

 and oyster reefs) 



The letter "A" denotes the western portion of the 

 Chenier Plain, and "B" denotes the eastern portion. 



The Chenier Plain Characterization is intended 

 for users having a moderate understanding of socio- 

 economic and ecological principles, and a concern 

 about resource management or coastal planning 

 problems. 



