2.2 Trampling and crushing of vegetation along shot line path and 

 access routes 



2.3 Creation of pathway for increased saltwater inundation 



2.4 Creation of pathway for increased rate of flow of runoff 



2.5 Change in frequency of inundation in localized areas 

 3. Attribute alterations 



The movement of work crews and marsh buggies over the land surface 

 tramples and crushes vegetation in a zone wider than that cleared 

 for shot placement. Depending upon the soil moisture conditions, 

 the vegetation may be completely uprooted and destroyed in some 

 areas. This decreases food and cover for the consumers in the area. 

 The total area thus affected is usually small in comparison to the 

 remaining area of productive vegetation, and the effects on animals, 

 nitrogen fixation, and detritus export are insignificant. 



The depth and number of ruts created by marsh buggies is dependent 

 upon the number of vehicles and the degree to which they retrace 

 existing tracks. In areas that are submerged daily, the depressions 

 are less likely to significantly alter water movement patterns. 

 Hence, in areas near the water's edge, confining of marsh buggy 

 traffic to a narrow corridor may be wise. However, in areas further 

 removed from the estuary, deep ruts resulting from retraced trails 

 form a depression for the movement 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 periods of time and (2) increase or decrease the 

 frequency of inundation of a given area of land. Areas dominated by 

 saltgrass or shore grass ( Monanthochloe littoral is ) may be replaced 

 by stands of smooth cordgrass 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. If 

 the affected area is close to the estuary, the frequency of inunda- 

 tion and detritus export may remain unchanged. However, the depres- 

 sions allow faster movement of water in both directions. This 

 increases turbidity and decreases the efficiency of the detritus- 

 filtering mechanism of the salt marsh. Thus a net increase of 



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