with such earthwork and subsequent runoff from exposed substrates 

 increase water turbidity levels in the activity area. Depending on 

 site location, the effects may be restricted to the immediate area 

 or distributed over a wider expanse. Plugging and/or filling 

 ditches, canals, and other open-water cuts removes existing or 

 potential aquatic environs for such consumer groups as the aquatic 

 invertebrates, fish, alligator, waterfowl, and some wading bird 

 species. Knocking down mounded substrates and reestablishing former 

 surface contours, however, may reform surface depressions and low 

 sites for the same consumer groups. 



Artificial revegetation facilitates rapid reintroduction of producer 

 biomass on denuded areas, thereby speeding the return to initial 

 site conditions. However, even revegetated areas may be less produc- 

 tive than were the original producers, until root-matting and other 

 restorative processes between the plants and soil have reestablished. 

 Native plant species provide food and cover resources most compatible 

 with requirements of nearby consumers and have the greatest probabil- 

 ity of successful establishment. Vegetative cover regulates surface- 

 water runoff from higher marsh sites, such as leveed roads, pads, 

 and other artificially elevated sites, and also moderates the scouring 

 effects of currents and boat-generated waves on barren substrates. 

 A potential source of water turbidity and sedimentation is thus 

 controlled. Revegetation helps return unproductive marsh areas to 

 some level of former productivity through reestablishment of the 

 detrital-nutrient pathway, which benefits detrital feeders, as well 

 as enhances the substrate for subsequent plant development. 



Removal of petrochemical and other waste products from storage pit 

 areas, from impregnated substrates around production facilities, and 

 from spill areas prevents potential long-term input of pollutants, 

 toxins, and other noxious substances into the marsh and their possi- 

 ble transfer through the food chain. Removal of soil toxins speeds 

 natural plant recovery processes. 



Land management objectives regulate which specific consumer groups 

 or plant assemblages are encouraged by planting techniques, filling 

 and removal processes, and other restoration procedures. These 

 objectives also determine, to a large extent, how extensive efforts 

 will be or in what direction restoration will proceed. 



Restoration typically occurs on sites which previously supported 

 various types of displacement-producing activities or sites which 

 have just recently been disturbed. Displacement, if it were to 

 occur, has already been effected by such prior processes. Addi- 

 tional effects are probably minor and temporary by comparison. Site 

 shutdown and restoration should, if successful, encourage the even- 

 tual return of sensitive wildlife species. 



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