regulating the water turbidity and standing water depth. If standing 

 water depth is irregular and shallow, shallow-water emergents and wet- 

 meadow components dominate. Constant deep water encourages dominance of 

 floating and submergent components if water turbidity is not too severe. 

 Marsh fauna, consequently, is determined by the dominant vegetation types. 

 Several waterfowl species and furbearers are especially attracted to par- 

 ticular sedges, rushes, and other select emergents for their food and for 

 certain cover requirements. Floating and submergent species are eaten by 

 several waterfowl species and also support a wide array of aquatic verte- 

 brates. Rectification of alterations caused by diking, ditching, and 

 channelization helps restore initial water circulation, intramarsh mixing 

 patterns, and sediment deposition. 



Reworking levees, filling in canals and pits, and removing surface flow- 

 lines destroys small quantities of producer biomass that may have become 

 established on such sites during the operational life of the operational 

 life of the facility. Favorable cover types attractive to selected wild- 

 life species may be lost during restoration procedures. Canal levees, 

 once vegetated with woody growth (primarily Baccharis spp. and Iva spp.), 

 are utilized by many species of mammals, birds, and reptiles. Suspended 

 sediments associated with such earthwork, combined with subsequent runoff 

 from exposed substrates in the activity area, increase water-turbidity 

 levels. Depending on site location and project magnitude, the effects 

 may be restricted to the immediate site or distributed over larger areas. 

 Water turbidity levels are rarely of major consequence, considering the 

 naturally high suspended sediment load of delta waters. Plugging and/or 

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

 potential aquatic environs for such consumer groups as the aquatic inverte- 

 brates, fish, alligator, waterfowl, and some wading bird species. Knocking 

 down mounded substrates and reestablishing former surface contours, how- 

 ever, may reform surface depressions and low sites for the same consumer 

 groups. Leveling mounded formations may, on the other hand, accelerate 

 the deleterious effects of the area's general subsidence. Land managers 

 may deem it more desirable to retain elevated areas rather than return to 

 submerged conditions. Local site conditions will determine which objec- 

 tive is more desirable. 



Artificial revegetation returns producer biomass to denuded areas, there- 

 by speeding the return to intial site conditions. Native plant species 

 provide food and cover resources most compatible with requirements of 

 nearby consumers. 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 controlled. Revegetation helps return 

 unproductive marsh areas to some level of former productivity through 

 reestablishment of the detrital-nutrient pathway which enhances the 

 substrate for subsequent plant development. Delta marsh flora includes a 

 wide variety of freshwater plants suitable for revegetation pruposes. 

 Numerous species beneficial to wildlife can be established using seeds, 

 whole transplants, or root stocks. 



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