The composition, abundance, and variability of the protist community in Port Everglades (Florida) estuary system was studied between September 1995 and August 1996. Surface water samples were collected from a fixed station in the port every two weeks and were examined using a modified Utermohl procedure to determine species composition and abundance. At the time the water samples were collected, a CTD cast was made to determine the surface salinity and water temperature, and to obtain a profile of the water column. The Secchi Depth was also measured at the time of the sample collection. Two hundred and eighty four species were identified during the course of the study. There were 187 diatom species, 51 dinoflagellate species, 8 chlorophyte species, 19 tintinnid species, 15 cyanophyte species, 1 silicoflagellate species, 1 chrysophycean species, 1 foraminiferan species, and 1 euglenophyte species identified as being at least present in the samples. The diatoms were the most abundant and most common species identified over the course of the year with the largest numbers being found during the rainy seasons. The most abundant diatom species were Skeletonema costatum, Pseudonitzschia pungens, and Thalassionema nitzschiodes. Protoperidinium pellucidum was the most abundant dinoflagellate present in the samples. The greater than 20 micrometer cell abundance ranged from a high of 3.67 x 105 cells liter-1 during the rainy season to a low 00.22 x 103 cells liter-1 during the dry season. The smaller than 20 micrometer cell abundance ranged from a high of 4.56 x 107 cells liter-1 during the rainy season, to a low of 1.23 x 106 cells liter-1 during the dry season. Species diversity was calculated using the Shannon index for each sample date. It ranged from a low of 0.0626 during the rainy season to a high of 1.51 towards the end of the dry season. Patterns exhibited by the 25 most abundant species identified during the study, the surface water temperature, and the salinity were evaluated using principal components analysis. Results of the analysis revealed one factor accounting for 22.0% of the variability. This factor exhibited a significant positive correlation with salinity, (r - 0.40), and distinguished between organisms with high and low salinity preferences. Two dinoflagellate species, one of the ciliate species, and three diatom species had high positive factor loadings for this principal component.
| Date of Award | Jan 1 1999 |
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| Original language | English |
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| Supervisor | Gary S. Kleppel (Supervisor), Richard E. Dodge (Advisor) & Gabriel Vargo (Advisor) |
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