Socioeconomic effects on physiography (C) in- 

 clude decisions that lead to development of natural 

 wetland areas for economic gain, or for human 

 leisure use. Examples include decisions to "reclaim" 

 wetland for agriculture or for duck habitat. 



Another major cause of wetland loss arises 

 from long-range hydrologic changes that accom- 

 pany canaling and other local wetland perturbation 

 (arrow from A to C in fig. 10). This same change in 

 local hydrology affects the natural resource pro- 

 ductivity (arrow from C to B). 



SUMMARY 



The generalized Chenier Plain basin ecosystem 

 and its critical wetland component is basically 

 driven by hydrologic forces. Habitat area changes 

 are primarily wetland loss to open water and to im- 

 poundments, resulting in modification of natural 

 resource productivity. All three of these processes 

 (hydrologic, habitat, and resource productivity 

 changes) are strongly influenced by the intensity of 

 human socioeconomic activity in the basin. 



LITERATURE CITED 



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