100 



50 



1955- 

 ,• 1978 



1935- 

 1958 



1900 



1925 1950 



YEAR 



1975 



2000 



Figure 6. Land loss not directly attributable to an increase in canal density 

 from 1890 to 1978 for three different intervals (Gagliano 1973; Wicker 1980). 



< 



UJ 



>- 



5 



Q. 

 M 



2 



ACTUAL 

 Johnson & 

 Gosselink, 

 19821 



PERMITTED, 



1981 

 preliminary 

 estimate, LA, 

 DNRl 



CM 



2000 



Figure 7. The area of canals added annually in the deltaic plain from 1891 

 based on analyses for three intervals (Gagliano 1973; Wicker 1980) extrapo- 



lated to an estimate for 1981 

 sources permits for the first 

 adjusted by an actual area to 

 and Gosselink 1982). 



based on Louisiana Department of Natural Re- 

 105 days (assuming 75 % in the deltaic plain) 

 permit area ratio of 1.46 computed by Johnson 



81 



