Dissolved Oxygen

 In general, waters throughout the area are well-

 oxygenated (Table 2). Daytime levels below 5.0 mg./L

 were measured only at Station 10. Mean oxygen content

 for the study period was highest at Stations 3 and 4.

 This is perhaps not surprising since both are located in

 lush growths of Thalassia and other algae and, in addition,

 have superb water clarity and good circulation due to their

 positions near the periphery of the study area. The high-

 est and the lowest levels of D.O. encountered were measured

 on March 21; 8.2 no./L at Station 2 and 4, and 4.6 mg./L

 at Station In (Table 9). Dissolved oxygen levels seemed

 to be unaffected by flood run-off following the May rain-

 storms. The data (Table 2) does not indicate any correla-

 tive changes. Monthly averages for eaci station are given

 in Table 15.


 EH
 The pH at all stations was usually between 8.2 and 8.4.

Of all the measurements made the lowest was 7.8 taken early

on the nornine of April 21 at Station 10. It will he shown

later, during analysis of the diurnal studies, that night-

time pH values can fall below 9.0. However, the lowest mid-

day value was 8.0. Like other variables measured, pl was

more chanaeable at shallower or more polluted spots. The


Pace 14