. The ecology of delta marshes of coastal Louisiana : a community profile. Marsh ecology -- Louisiana; Wetlands -- Louisiana. Figure 24. Computerized re-creation of the west side of Barataria Bay showing the change in wetlands between 1945 (a) and 1980 (b). Black is open water; marshes are shown as varying shades of grey (Dozier 1983). large a delta as it has historically. In addition,channeling and leveeing the river entrains much of the sediment, preventing spring overbank flooding that nourishes the interdistributary marshes. There is now strong evidence that the rate of marsh loss is being
. The ecology of delta marshes of coastal Louisiana : a community profile. Marsh ecology -- Louisiana; Wetlands -- Louisiana. Figure 24. Computerized re-creation of the west side of Barataria Bay showing the change in wetlands between 1945 (a) and 1980 (b). Black is open water; marshes are shown as varying shades of grey (Dozier 1983). large a delta as it has historically. In addition,channeling and leveeing the river entrains much of the sediment, preventing spring overbank flooding that nourishes the interdistributary marshes. There is now strong evidence that the rate of marsh loss is being accelerated by local human activities in addition to the reduction in the river's sediment load. Canals are the major culprit in this scenario. Formerly, rain runoff from adjacent uplands flowed across wetlands, dropping its load of sediment and nourishing the marshes. Now a network of drainage canals along the marsh-upland interfaces of the delta estuaries carries this runoff directly into estuarine lakes and bays, bypassing the swamps and marshes (Conner and Day 1982). If runoff flowed across the wetlands, the trapped sediment would help minimize wetland subsidence and the quality of the runoff water would be improved before it entered the lakes and bays. Instead, the portions of the estuaries near urban areas are becoming increasingly turbid and eutrophic (Craig et al. 1977). At the other end of the estuary, navigation canals, especially those that cross the barrier islands, cause major disruption of circulation. The canals are straight and deep in estuaries that have an average depth of only 1 or 2 m. There- fore they capture flow from smaller 25. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Gosselink, James G; National Coastal Ecosystems Team (U. S. ). Washington, DC : National Coastal Ecosystems Te
Size: 1254px × 1994px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookcollectionbio, booksubjectwetlandslouisiana
