(2) Planting operations (10-meter-wide, landward to seaward 

 planting) : 



(a) Sprigs - $12 per linear meter. 



(b) Nursery seedlings - $28 per linear meter. 



(c) Plugs - $35 per linear meter. 



(3) Fertilization (10-meter-wide, landward to seaward planting): 



(a) Soluble - $0.15 to $0.25 per linear meter. 



(b) Slow-release - $1 to $4 per linear meter. 



IX. IMPACT ASSESSMENT 



1. Potential Benefits. 



Salt marshes are valued as sources of primary production (energy), as 

 nursery grounds for sport and commercial fishery species, and as a system for 

 storing and recycling nutrients and pollutants such as nitrogen, phosphorus, 

 and heavy metals. Once established, erosion control plantings function as 

 natural salt marshes and gradually develop comparable animal populations 

 (Cammen, 1976; Cammen, Seneca, and Copeland, 1976). 



a. Marsh Ecology . Little of the biomass of salt marsh, about 5 percent, 

 is consumed while the plant material is still living. Grasshoppers and plant 

 hoppers graze on the grass and are, in turn, eaten by spiders and birds. 

 Direct consumption of rhizomes and culms of marsh grasses by waterfowl may be 

 significant locally near waterfowl wintering grounds. Periwinkles graze on 

 algae growing on the grass. The majority of the energy is believed to move 

 through the detrital food chain. Dead grass is broken down by bacteria in the 

 surrounding waters and on the surface of the marsh. This process greatly 

 decreases the total energy but increases the concentration of protein, 

 thereby, Increasing the food value. Some detrital particles and mud algae are 

 eaten by a variety of detritus feeders such as fiddler crabs , snails , and 

 mussels; these organisms are, in turn, eaten by mud crabs, rails, and 

 raccoons. The remaining detritus, augmented by the dead matter from the 

 primary and secondary consumers, is washed from the marsh by tidal action as 

 new export. This exported detritus, with material from submergent aquatic 

 plants and the plankton, feeds the myriad of larvae and mature fish and 

 shellfish which use estuaries, bays, and adjoining shallow waters. Marsh 

 grasses may account for most of the primary production of the system in waters 

 where high turbidity reduces light penetration, thereby reducing phytoplankton 

 and submergent aquatic production. 



The productivity and utilization of high marsh has received less attention 

 than that of low marsh. Indications are that net production of some high 

 marsh may equal that of many low marshes. The important difference, however, 

 is that the export mechanism of frequent tidal flushing is absent in high 

 marsh. Consequently, much of the high marsh biomass goes into peat formation, 

 in situ rather than into the estuarine food chain. For this reason, high 

 marsh appears to be of much less direct value to the estuary. 



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