TABLES 



Nu"iber Page 



1 Salinity values (ppt) recorded by various investigators for delta 



marshes 6 



2 Classification of coastal marshes of the Mississippi River Delta, and 



area of different marsh zones in 1978 6 



3 Average coastal subnergence on the U.S. east and gulf coasts 13 



4 Land-use changes along the northwest edge of the Barataria basin, on 



the Bayou Lafourche natural levee 26 



5 Land use changes, in hectares, in the Mississippi Delta, 1955-78 27 



5 Regression analyses relating net primary production (NPP) and inshore 

 shrimp production (1955-74) in hydrologic units to various physical 

 parameters 32 



7 The annual duration and frequency of inundation of marshes in the 



Barataria basin, Louisiana 33 



3 Marsh accretion rates (mm/yr) in Louisiana delta marshes, based on the 



1963 ^''Cs fallout peak 35 



9 Concentration (C) and accumulation rates (A) of organic carbon, 



nitrogen, phosphorus, iron, and manganese in Louisiana delta marsh 



soil s 35 



10 Multiple linear regression models of soil ions showing what factors 



control their distribution 36 



11 The ratio of the major cations to the chloride ion in normal seawater 

 and in the saline, brackish, inte mediate, and fresh marshes of 



Louisiana 37 



12 Percent cover of the dominant plant species in major marsh zones of 



the Louisiana coast 38 



13 Production of marsh vascular plant species in the Mississippi Delta .... 45 



14 Belowground biomass of Mississippi delta marsh plant species 48 



15 Production estimates for a Spartina alterniflora stand based on 



different techniques 48 



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