of the 1,200-foot sea oats dune to the north end of the 1,100-foot 

 bitter panicum dune received the most sand during this study. 

 This same pattern was also noted in an earlier study (Dahl, et 

 al., 1975). However, the relative rates of sand accumulation may 

 change from year to year along this stretch of beach. 



f?. Sand Volumes above Planting Elevation for 100-foot Segment 

 in the Foredunes . Sand volumes were measured from early in 1970 

 m those areas immediately affected by the experimental dune 

 plantings (Dahl, et al., 1975). For most surveys of the 100-foot 

 cross sections, about 25 feet on either side of the plantings was 

 measured. This measurement was continued through the 1976 

 surveys for comparison purposes. The values are tabulated in 

 Table 3 and Figure 11. The dune-width extension plantings were not 

 included in these measurements. 



Although total sand in the entire beach system did not 

 accrete on the 1,200-foot sea oats dune during 1975-76, modest 

 increases influenced by the plantings did occur on this 100-foot 

 segment. Accumulations above the 4-foot (1.2 meters) MSL planting 

 elevation in August 1976 were three times those of a similar 

 segment of unplanted beach. The younger bitter panicum plantings 

 also had 2 to 2.5 times more sand in the planting locale than the 

 unplanted area had (Table 3). Therefore, the plantings adequately 

 confined the migrating beach sand to the planting area as intended. 



c. Sand Volumes of 290-foot (88 meters) Segment of the Foredune . 

 For a better evaluation of the role of artificial dune building 

 through revegetation, it was necessary to study more than the 

 100-foot segment immediately over the plantings proper because 

 the plantings influence sand accumulation for a much greater 

 distance, particularly in front. Figures 12 to 17 and Tables 

 4 and 5 show the sand accumulation for a 290-foot segment. This 

 distance includes the area of the 100-foot segment over the plantings, 

 Basically, it extends 100 feet seaward of the current grass 

 extension, and 190 feet landward. This 290 feet is far enough to 

 reach beyond the influence of the plantings on sand accumulation in 

 both directions. 



Total sand accumulation in the unplanted area is well below 

 that for the planted dunes (Table 4). However, for this larger 

 segment of the beach system, the unplanted study area accumulated 

 about as much sand from August 1975 to August 1976 as the planted 

 study segments did (Table 6). This trend is expected to continue, 

 at least until a major surge again denudes the area, for two 

 major reasons. First, there is sufficient pioneer vegetation 

 established in the unplanted area to trap all sand moving through 

 the foredune area. The area has numerous "pimple" dunes that 

 are accumulating sand but no continuous dunes of any kind yet 



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