Tide Level Data 



Erratic water level fluctuations contribute to increased marsh erosion rates and reduce the ability 

 of vegetation to become re-established in open water areas. Tide levels both inside and outside 

 of the management area have been monitored by TLT at weir 1 to assess if tide fluctuations are 

 being reduced inside of the management area. Elevations were frequently monitored (86 times 

 from 25 March 1986 through 26 November 1988, and 82 times from 1 December 1986 through 28 

 November 1987). 



Salinity Levels 



Salinity readings have been collected by TLT on a periodic basis at 12 sites from 11 November 



1985 through 28 November 1987. See Figures 3 and 4 for the location of the sites monitored in 



1986 and 1987. 



Vegetative Changes 



In 1988, 22 60-m vegetative transects were established so that plant communities could be 

 monitored yearly. These transects are located throughout the fresh, intermediate, and brackish 

 marsh, and in open water (Figure 5). Each transect is divided into 10 5-m increments. All 

 vegetative species are identified annually within a 1-m radius at each increment. 



A visual estimate of species composition is also made at each transect site location. The 

 estimate gives a percentage of each species in relation to all other plant species in the community. 

 It is important to know if the management plan is increasing or decreasing the abundance of plant 

 species at each transect site, and if the plant communities are changing to species favoring a fresh, 

 intermediate, brackish, or strong brackish marsh. An evaluation system has been developed to show 



Figure 3. Sites monitored for salinity in 1986. 



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