Marsh buggy tracks affect land elevation and create pathways for 

 increased saltwater inundation. The depth and number of ruts created 

 by marsh buggies is dependent upon the number of vehicles used and 

 the degree to which they retrace existing paths. In areas that are 

 submerged daily, the depressions are less likely to significantly 

 alter water-movement patterns. Hence, confinement of marsh buggy 

 traffic to a narrow corridor in areas near the estuary may be wise. 

 However, in areas further removed from the water's edge, deep ruts 

 resulting from retraced trails would form depressions for the move- 

 ment of water and, if deep enough, may result in standing bodies of 

 water after the tide has receded. The orientation and depth of the 

 depressions determine whether they (1) remain for long time periods 

 and (2) increase or decrease the frequency of inundation of a given 

 area of land. Areas dominated by saltgrass or shore grass may be 

 replaced by stands of smooth cord-grass when the frequency and/or 

 duration of inundation increases. The converse may occur when 

 frequency and/or duration of inundation decreases. The total area 

 affected is site specific and could range from insignificant to 

 highly significant when compared to the total area of salt marsh. 

 Consumers that depend upon smooth cordgrass and its epiphytes for 

 food and/or cover may ultimately increase or decrease. The amount 

 of detritus exported to the adjacent estuarine system is directly 

 proportional to the standing crop of smooth cordgrass. 



Beyond the impacts of direct spoil placement on the marsh and crea- 

 tion of deep (three-m) aquatic ecosystems, the canal also creates 

 a large route for increased saltwater inundation (Bourn and Cottam, 

 1950; Gagliano, 1973; Copeland and Dickens, 1974; Darnell, 1976). 

 The pattern and height of spoil placement are the most important 

 factors that determine whether the daily tides are contained within 

 a localized zone or whether they may inundate extensive areas. 

 Thus, the total area affected is site specific and could range from 

 the site alone to a large proportion of the marsh area, depending 

 upon topography and tidal hydraulics. 



Water flow in the canal may change depending upon canal location and 

 area within the canal system. In the straight sections of the 

 canal, within the ralm of tidal influence, there is an increase in 

 the volume of water exchange (Gagliano, 1973). There may be an 

 acceleration of freshwater runoff from the marsh (Copeland and 

 Dickens, 1974; Darnell, 1976). This can result in a lowering of the 

 water table and a drying of higher marsh areas. 



On the other hand, the spoil placement may so block the natural 

 marsh drainage that the marsh area is effectively impounded. In 

 some instances the plants may be exposed to increased salinities and 

 acid conditions. In other instances the impounded marsh area may 

 have a lowered salinity regime and contain plant characteristics of 

 brackish and fresh marshes (Conner et al., 1976). 



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