CONTENTS 



Page 



PREFACE iii 



FIGURES ix 



TABLES xiii 



CONVERSION FACTORS xvi 



GLOSSARY xvii 



ACKNOWLEDGEMENTS xviii 



1 .0 THE ECOLOGICAL CHARACTERIZATION PROCESS 1 



1.1 INTRODUCTION 1 



1 .2 CHENIER PLAIN ECOLOGICAL CHARACTERIZATION 1 



1.2.1 Approach of the Study 1 



1.2.2 Organization of Contents 2 



1.2.3 Audience 2 



2.0 THE CHENIER PLAIN ECOSYSTEM 9 



2.1 INTRODUCTION 9 



2.2 GEOLOGICAL PROCESSES 9 



2.2.1 Sea Level Changes 9 



2.2.2 Land Subsidence 9 



2.2.3 Recent Sedimentary Environments 10 



2.2.4 Chenier Ridges 10 



2.2.5 Nearshore Topography 15 



2.3 HYDROCLIMATE 15 



2.3.1 Water Budget 19 



2.3.2 Synoptic Weather Types 19 



2.4 NEARSHORE HYDROLOGIC PROCESSES 21 



2.5 GROUND WATER 21 



2.5.1 Usage of Ground Water 22 



2.5.2 Effects of Withdrawals 23 



3.0 CHENIER PLAIN BASINS 25 



3.1 INTRODUCTION-GENERALIZED BASIN DESCRIPTION 25 



3.1.1 Hy drologic Processes in a Basin 25 



3.1.2 Land-Modifying Processes 25 



3.1.3 Basin Renewable Resource Productivity (RRP) 27 



3.1 .4 Socioeconomic Processes 27 



3.2 SOCIOECONOMICS 27 



3.2.1 Introduction 27 



3.2.2 Minerals 29 



3.2.3 Agriculture 33 



3.2.4 Commercial Trapping and Fishing 38 



3.2.5 Sport Hunting and Fishing 47 



3.2.6 Commerce, Industry, and the Resident Population 52 



3.2.7 Transportation 55 



3.2.8 Government 60 



3.2.9 Summary 61 



3.3 HYDRODYNAMICS 61 



3.3.1 Introduction 61 



3.3.2 Approach 61 



3.3.3 Subunits Having Direct Exchange With the Gulf 62 



3.3.4 Subunits Influenced by Freshwater 66 



3.3.5 Subunits Dominated by Wind-Driven Currents 68 



3.3.6 Subunits of Exchange Between Water Bodies and Wetlands 70 



3.3.7 Subunits With Little or no Water Exchange-Uplands and Impoundments 71 



3.3.8 Human Impacts on the Hydrologic Regime 71 



3.4 HABITATS AND LAND-MODIFYING PROCESSES 74 



3.4.1 Introduction 74 



3.4.2 Approach 75 



3.4.3 Present Habitat Composition and Distribution 75 



3.4.4 Historical Changes in Habitat Composition and Distribution 77 



3.4.5 Habitat Change by Direct Human Action 78 



3.4.6 Natural Habitat Changes and Indirect Changes Caused by Man 79 



