The July 1986 REMOTS® sample size at the CLIS mounds was 

 reduced by one third from that taken in August 1985. Although 

 three replicate photographs were obtained at each station, only one 

 replicate was analyzed. This reduced data base has tended to 

 compromise the statistical comparison of the different disposal 

 mounds between years. In particular, it was difficult to evaluate 

 within-station patchiness in the occurrence of Stage III taxa, so 

 that apparent changes in successional stage between 1985 and 1986 

 could not be determined adeguately. Analysis of only one replicate 

 photograph allowed a greater number of stations to be sampled, thus 

 increasing spatial coverage of the different disposal mounds while 

 sacrificing the assessment of small-scale variability. In order 

 to insure statistical integrity between surveys, it is recommended 

 that all future REMOTS® monitoring at the CLIS site be based on an 

 analysis of a minimum of three station replicates. 



4.4 Sediment Chemical Analysis 



Another objective of the July 1986 field operations was 

 to determine the concentrations of selected chemical constituents 

 in sediments from each of the ten disposal mounds and the new 

 reference station. It is instructive to compare the results of the 

 chemical analyses with other studies which have reported the 

 concentrations of metals and PCBs in Long Island Sound sediments 

 (Table 4-2). Benninger et al. (1979) measured the concentrations 

 of Zn, Cu, and Pb in a sediment core collected in Central Long 

 Island Sound. The Zn and Cu concentrations detected in the top 10 

 cm of the sediment core were comparable, or slightly higher than 

 the reference levels found in the present study (Table 4-2) . 

 However, the Pb concentrations reported by Benninger et al. (1979) 

 were lower than those found at the reference station in the present 

 study . 



Greig et al. (1977) measured the concentrations of a 

 suite of trace metals in the top four cm of sediment at stations 

 throughout Long Island Sound. In his study, sediments in the 

 vicinity of the new CLIS reference station showed similar, or 

 slightly higher concentrations of Zn, Cu, Cr, and Hg compared with 

 the results of the present study (Table 4-2) . As in comparisons 

 with Benninger et al., Pb concentrations were lower than those 

 found in the present study at the reference station. Cd levels 

 were below the analytical detection limit in both Greig 's and the 

 present study; however, his detection limits were considerably 

 lower. Similarly, the levels of Ni measured by Grieg were below 

 the 28 ppm detection limit in the present study (Table 4-2) . 



This above observations are consistent with data from 

 Munns et al. (in press), who reported lower concentrations of Pb 

 and higher concentrations of Zn, Cu, and Cr for CLIS reference 

 station samples. The levels of Cd and Ni detected by Munns were 

 lower than the detection limits of the present study, while percent 



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