Artificial revegetation introduces producer biomass on denuded areas, 

 thereby speeding the return to initial site conditions. Native plant 

 species provide food and cover resources most compatible with require- 

 ments of nearby consumers. Vegetative cover regulates surface-water 

 runoff from higher marsh sites such as leveed roads, pads, and other 

 artificially elevated sites. It also moderates the scouring effects of 

 currents and boat-generated waves on barren substrates. A potential 

 source of water turbidity and sedimentation is controlled. Revegation 

 helps return unproductive marsh areas to some level of former productiv- 

 ity through reestablishment of the detrital-nutrient pathway, which 

 enhances the substrate for subsequent plant development. Fresh marsh 

 flora includes a wide variety of plants suitable for revegetation pur- 

 poses. Numerous species beneficial to wildlife can be established using 

 seeds, whole transplants, or root stocks. 



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 and bioaccumulation of heavy 

 metals, petrochemical hydrocarbons, brine, and other noxious substances 

 in the marsh. Removal of soil toxins speeds natural 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. They also deter- 

 mine, to a large extent, how extensive efforts will be or in what 

 direction restoration will proceed. 



Displacement factors should be considered for all phases of activities. 

 Restoration typically occurs on sites which have already been disturbed. 

 Displacement, if it were to occur, has already been effected by prior 

 processes. Additional effects are probably minor and temporary in nature. 

 Site shutdown and restoration should, if successful, encourage the return 

 of sensitive wildlife species. 



4. Key attribute alterations 



Restoration of the hydrologic regime is the pivotal aspect of site 

 rehabilitation, which controls or combines with other less critical 

 regulatory parameters and ultimately determines the health and subsequent 

 productivity of the fresh marsh environment. The hydroperiod determines 

 how much water covers the marsh, how long the marsh is submerged, how 

 frequently the substrate is exposed above the water table, and what the 

 salinity range may be. Standing water also provides cover for numerous 

 aquatic and semi aquatic consumer species and provides a mechanism for 

 transporting detritus and dissolved nutrients. Second-order effects 

 include regulation of gaseous exchanges between substrate and plants and 

 the regulation of nutrient availability. Reestablishing prior drainage 

 pathways and surface contours and unblocking former sources of water 

 inflow by filling in or plugging canals, removing or breaching continuous 



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