cover maps indicates that both Batis maritima and 

 Borrichia frutescens decreased in cover in June 1998 and 

 1999 compared to other springs, while Monanthocloe 

 littoralis, Salkomia virginica and bare area had increased. 

 The most evident vegetation changes appeared have 

 occurred in the front section of the transect, which was 

 lower and subjected to more influence from freshwater 

 diversions. The maps also indicate that M. littoralis was 

 commonly found in the back section of the transect, an 

 area that was rarely flooded. Furthermore, the greatest 

 bare area was found in the back part of the transect, an 

 area that remained relatively constant throughout the 

 spring periods. 



July 1997 Composite Event - The July 1997 event 

 resulted in few changes at the Reference Station 

 (Figures 6-14a and 6-14d). Only 8.5 cm (3.4 inches) of 

 rain fell in the study area between the June and August 

 sampling period. The most obvious change was a 

 temporary increase in Batis maritima cover from 1.7% in 

 June to 12% in August (Table 6-5). The increase in B. 

 maritima corresponded to a 4-fold decrease in Borrichia 

 frutescens. However, B. maritima cover quickly dropped 

 back to 1.5% in November 1997, and B. frutescens 

 increased. Bare area also decreased slighdy by 5% 

 between June and August but increased quickly 

 afterwards. 



At Station II, the vegetation was inundated by water 

 through the Rincon Overflow Channel and 

 precipitation during the event. Following the event, 

 Batis maritima cover increased 3.4% but decreased to its 

 pre-event cover in November 1997 (Figures 6- 15a 

 through 6-15c) (Table 6-5). Monanthocloe littoralis cover 

 increased by ~7% in August but returned to its pre- 

 flood values in November as well. The increase in 

 these species direcdy following the event corresponded 

 to an 11% decrease in bare area. Bare area also 

 increased quickly thereafter. 



At Station III, Batis maritima cover increased 22% in 

 August following the event but dropped dramatically 

 by 34% from August to November (Table 6-5). The 

 increase in B. maritima occurred in the front section of 

 the transect, and corresponded to a decrease in 

 Borrichia frutescens and a reduction in bare area to almost 

 0% in that section of the transect (Figures 6- 16a and 



6- 16b). B. maritima cover retreated in November, and 

 the B. frutescens zone near the back of the front section 

 of the transect began to recover (Figure 6-16c). 



October 1998 Composite Event - At the Reference 

 Station, few changes were seen in the transect during 

 the two sampling periods following the event; 

 however, major changes were seen the following spring 

 (Figures 6-17a through 6-17d). GIS analyses indicate 

 that in June 1999, Salicomia higelovii expansion into 

 previously bare areas had occurred. The increase in 

 S. higelovii also corresponded with a decrease in 

 Monanthocloe littoralis and an increase in Batis maritima 

 cover. 



During the October 1998 event, diversions through the 

 Rincon Overflow Channel were significant enough to 

 wash out the road crossing at the north end of the 

 channel, inundating Station II with freshwater. In the 

 sampling periods following the October 1998 event, 

 several significant changes in vegetation percent cover 

 occurred (Figures 6- 18a through 6-18d). Bare area 

 decreased gradually from 86% in October 1998 to 14% 

 in June 1999. The decrease in bare area began as an 

 increase in Monanthocloe littoralis cover. However, by the 

 following spring, Salicomia higelovii had occupied almost 

 all previously bare area and several parts of the transect 

 previously occupied by M. littoralis. 



Few changes were seen in the transect at Station III 

 following the October 1998 event (Figure 6-19). 



September 1999 Composite Event - At the 



Reference Station, a major increase in bare area 

 occurred following flooding of the transect due to the 

 tidal surge of Hurricane Bret in August 1999 

 (Figures 6- 19a and 6- 19b). Afterwards, 42.5 cm 

 (17 inches) of rain fell between September and 

 December, leading to noticeable vegetation increases 

 and bare area decreases. Monanthocloe littoralis cover 

 quickly filled in almost half of the bare area by 

 December 1999 (Figure 6- 19c). Bare area continued to 

 decrease in June 2000 and both Batis maritima and 

 Salicomia higelovii covet increased (Figure 6-19d). 



Chester Six ♦ 6-27 



