7388

• UCREFRP Catalog Number: 7388
• Author: Ohmart, R. D., B. W. Anderson and W. C. Hunter.
• Title: Ecology of the Lower Colorado River from Davis Dam to the Mexico-United States International Boundary
• USFW Year: 1988.
• USFW - Doc Type: A Community Profile.
• Copyright Material: NO

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PREFACE ................................................................... III
CONVERSION TABLE .......................................................... IV
FIGURES ................................................................... viii
TABLES .................................................................... xli
ACKNOWLEDGMENTS ........................................................... xvi
CHAPTER 1. INTRODUCTION ................................................... 1
1.1 STUDY AREA DESCRIPTION ........................................... 2
1.2 CLIMATE .......................................................... 6
1.3 RIPARIAN VEGETATION OF THE FLOODPLAIN............................ 9
CHAPTER 2. HISTORY OF THE LOWER COLORADO RIVER ........................... 15
2.1 GENERAL HISTORY OF HUMAN USE..................................... 15
2.2 FLORAL CHANGES.... ............................................... 19
2.3 FAUNAL CHANGES ................................................... 26
CHAPTER 3. HYDROLOGIC, LIMNOLOGICAL, AND TERRESTRIAL PHYSICOCHEMICAL
CHARACTERISTICS OF THE LOWER COLORADO RIVER SYSTEM............... 30
3.1 HYDROLOGY., ...................................................... 30
3.2 WATER QUALITY... ................................................. 37
3.3 FLOODPLAIN AND TERRACE SOILS AND SALINITY ........................ 55
CHAPTER 4. AGRICULTURAL USES OF THE VALLEY ............................... 56
4.1 AGRICULTURAL PRODUCTION .......................................... 56
4.2 AGRICULTURAL FEATURES AND PRACTICES AND USE BY WILDLIFE.......... 59
CHAPTER 5. OTHER HUMAN USES OF THE VALLEY................................ 64
5.1 WATER-RELATED RECREATION ......................................... 64
5.2 RECREATIONAL AND TRAILER PARKS ................................... 64
5.3 IMPORTANCE OF RECREATION LANDS................................... 65
5.4 FISHING AND HUNTING RESOURCES. ..... o .... o.o..*soooo**oooosso*** .. 66
5.5 URBAN DEVELOPMENT ................................................ 66
CHAPTER 6. RECENT TRENDS IN RIPARIAN HABITAT CHANGES ON THE LOWER COLORADO
RIVER ............................................................. 68
68
6.1 PARKER II HABITAT CHANGES ........................................
6.2 RIPARIAN HABITATS FROM 1976-1986 ................................. 72
6.3 MARSH HABITATS ON THE LOWER COLORADO RIVER ....................... 79
CHAPTER 7. PLANT COMMUNITIES ............................................. 81
7.1 AQUATIC MICROPHYTES ........................................... 81
81
7.2 AQUATIC MACROPHYTES .............................................. 81
7.3 EMERGENT PLANTS .................................................. 83
7.4 WOODY RIPARIAN PLANTS............................................ 84
7.5 DESERT VEGETATION... ............................................. 84
7.6 LISTED SPECIES AND THREATENED HABITATS ........................... 85
CHAPTER 8. INVERTEBRATE COMMUNITIES ...................................... 87
8.1 AQUATIC INVERTEBRATES............................................ 87
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