PREFACE 



The Conference on Coastal Erosion and Wetland Modification in Louisiana, 

 sponsored by the Louisiana Universities Marine Consortium and the U.S. Fish and Wildlife 

 Service, was held in Baton Rouge on 5-7 October 1981. The Conference was in response 

 to a need for a current compendium of information on the causes, consequences, and 

 options to deal with coastal land loss in Louisiana. 



Patterns of wetlands deterioration in relation to natural geomorphic processes in 

 the Mississippi River delta were described as early as the I930's (Russell, R.J. 1936. 

 Physiography of the Lower Mississippi River delta: Louisiana Geological Survey, Lower 

 Mississippi Delta Geological Bulletin 8: 3-199). In the I960's systematic comparisons of 

 wetland areas from topographic maps indicated that the net loss of wetlands in Louisiana 

 was 42.7 km^ (16.5 mi /yr) (Gagliano, S.M. and J.L. van Beek 1970. Geologic and 

 geomorphic aspects of deltaic processes, Mississippi delta system. Louisiana State Univ. 

 Center for Wetland Resources, Baton Rouge. Hydrologic and Geologic Studies of Coastal 

 Louisiana. Rep. I. 140 pp.). Habitat mapping studies conducted in the late I970's for the 

 U.S. Fish and Wildlife Service and based on direct analyses of aerial imagery yielded 

 estimates of coastal wetland loss of 18 km /yr in the chenier plain region of 

 southwestern Louisiana between 1952 and 1974 (Gosselink, J.G., C.L. Cordes and J.W. 

 Parsons. 1979. An ecological characterization of the chenier plain coastal ecosystem of 

 Louisiana and Texas. U.S. Fish and Wildlife Service, Office of Biological Services. 

 FWS/OBS-78-9) and 83 km /yr in the deltaic plain of southeastern Louisiana between 

 1955-56 and 1978 (Wicker, K.M. 1980. Misissippi Deltaic Plain Region ecological 

 characterization: a habitat mapping study. A user's guide to the habitat maps. U.S. Fish 

 and Wildlife Service, Office of Biololgcal Services. FWS/OBS-79/07). Furthermore, 

 comparisons of land loss rates estimated for various intervals during this century indicate 

 a geometric increase in this rate with time, the extrapolation of which yields a 1980 rate 

 of 102 km /yr (39.4 mi'^/yr) for the Mississippi deltaic plain alone (Gagliano, S.M., K.J. 

 Meyer-Arendt, and K.M. Wicker. 1981. Land loss in the Mississippi River deltaic plain. 

 Trans. Gulf Coast Assoc. Geol. Soc. 31:295-300). 



These revelations have heightened public and governmental concern about the 

 causes and consequences of the astounding rates of coastal environmental change in 

 Louisiana and have catalyzed action on various approaches to slow or reverse the rate of 

 loss. The causes are clearly complex but involve at least the senescence of the active 

 delta, regional and localized subsidence, leveeing of the Mississippi River, and the 

 effects of channelization of wetlands. Man has played a major role, in consert with 

 natural processes, in accelerating coastal land loss. The potential effects of these 

 coastal changes on living resources, state revenues and human society are massive. The 

 coastal wetlands of Louisiana are a major contributor to national fisheries and wildlife 

 resources. Given the present rates of loss, several coastal parishes have life 

 expectancies in the range of 50 to 100 years, and enormous social and economic 

 dislocations would result. 



Several structural and management approaches to stemming coastal land loss have 

 been proposed. These range from allowing the wholesale diversion of the Mississippi 

 River down the Atchafalaya River to promote rapid delta building to more restrictive 



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