The Phytoplankton Ecology of Wilson Inlet, Western Australia - Primary Production

Full description

Salinity, temperature, dissolved oxygen, chlorophyll a, diffuse light attentuation coefficient for photosynthetically active radiation were collected to measure photosynthesis and estimate the net rate of depth integrated primary productivity of the phytoplankton community in Wilson Inlet. The total annual primary productivity in Wilson Inlet was determined and compared with other estuarine and aquatic environment throughout the world.

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Maintenance and Update Frequency: notPlanned

Statement: Samples were collected on 20 field trips at Wilson Inlet from July 1997 through November 1998. Field trips were conducted at monthly intervals with increased sampling during the spring phytoplankton blooms. Three sampling sites were chosen to encompass spatial variability within the estuary; site 1 near the ocean entrance; site 2 in teh western basin and; site 3 in the eastern basin (see Fig 3.1 of the thesis). Vertical profiles of salinity, temperature and dissolved oxygen were determined with a Hydrolab H2O multiprobe (Hydrolab Corporation, Austin Texas, USA) at 0.5 m intervals from the surface to the bottom. The diffuse light attentuation coefficient (k) for photosynthetically active radiation (PAR) was determined using a LiCor 185B meter and a 30-cm-diameter Secchi disk. Water samples for chlorophyll a determination were collected at the surface, bottom and through the water column. An integrated water column sample was collected by mixing 1-L of water from each 0.5 m interval from the surface to the bottom in a 20-L bucket. Chlorophyll a samples were collected by filtering a known volume of sample water through 47 mm GF/C (Whatman) filters. The filters were stored below 4 degrees Celsius and prepared for analysis immediately upon return to the laboratory. The chlorophyll a concentration was determined by acetone extraction and analysed by spectrophotmetry. Primary production experiments were conducted on homogeneous water-column samples, which were collected using the methods described above. The collected water was homogenised and screened with 200 um mesh to remove largezooplankton grazers. A 1 L aliquot was decanted into a rinsed polycarbonate bottle and stored in the shade prior to analysis. For further methods see section 4.4 of the thesis.

Notes

Credit
National Eutrophication Management Program and Water and Rivers Commission of WA (now Department of Water)