CORLISS and TRENT: PHYTOPLANKTON PRODUCTION 



any station (Table 1). Surface water temiier- 

 atures were slightly higher in the canals and 

 bay than in the marsh. 



Turbidity values of surface water samples 

 varied as much as 41.5 JTU between stations 

 on June 25 and as much as 41 JTU between 

 dates at station 5 (Table 1). Average turbidity 

 values from the marsh and Ijay stations were 

 about double those from the canal stations. On 

 June 25, however, turbidities in the bay were 

 about twice those in the marsh and about four 

 times those in the canals. 



Insolation was similar on all sampling dates. 

 The daily averages ranged from 0.82 to 0.85 

 cal/cmVday. 



Overproduction of phytoplankton, in terms of 

 oxygen balance, occurred in some canals of the 

 development. Plankton blooms that reduced 

 oxygen to zero at night, and caused fish kills at 

 station 1, occurred at least three times during 

 the study period. These blooms were observed 

 on July 4, July 18, and August 7. 



PRODUCTION AND RESPIRATION 



Average gross production ranged from 1.17 

 at station 5 to 2.25 mg carbon/liter/day at sta- 

 tion 1 during the study (Table 2 and Figure 2). 

 Average values at the two canal stations were 

 almost identical. Likewise, there was almost no 

 difference between average values at the two 

 marsh stations. Average production in the ca- 

 nals was slightly higher (B'r ) than in the marsh 

 and much higher (48^^^^) than in the bay. In 

 similar studies in Boca Ciega Bay, Fla., Taylor 

 and Saloman (1968) reported that primary pro- 

 duction of phytojilankton did not differ consis- 

 tently between development canals and open bay 

 areas. 



Average net production ranged from 0.84 at 

 station 5 to 1.74 mg carbon/liter/day at station 1. 

 Like gi'oss production, the values were about 

 the same among canal stations and among marsh 

 stations. Average net production in the canals 

 was 13''r higher than in the marsh and 51 "^r 

 higher than in the Bay. 



Respiration averaged 0.51 mg carbon/ liter/ 

 day, or 27.7 ^v of gross production and ranged 

 from 23.4 to 34.4% between stations (Table 2). 



Tahuc 2. — Net production (NP), re.spiration (fi), gross 

 production (GP), and percent respiration (%R) by 

 station and date in West Bay, Tex. 



Distinct differences in the percents of gross pro- 

 duction attributable to respiration between canal, 

 marsh, and bay areas were not apparent. 



Averages of gross and net iiroduction in the 

 canals and marsh were significantly greater 

 than in the bay; differences between the canals 

 and marsh were not significant (Table 3). 



The differences in production between stations 

 were related to turbidity. The correlation co- 

 efficient (r) between average gross production 

 and average turbidity at each station was — 0.70. 



Table 3. — Compari.sons of net productivity, respiration, 

 and gross productivity between stations (one-way anal- 

 ysis of variance). 



831 



