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Results |
DO
Comparing the CTD and Winkler methods for determining DO, a R2 = 0.9397 resulted taking away one outlier (Figure 1)(UWT 2002).
The lowest levels of DO were found off the shelf in the Pacific Ocean at 750 to 805 meter depths with 2.558 and 2.563 ml/l
respectively and DO levels of 3.273 and 4.559 ml/l were found at 1459 and 2299 meter depths respectively (Figure 2).
Figure 1. Comparing the CTD and Winkler method of determining DO for the longitudinal Puget Sound study (UWT 2002).
Figure 2. DO levels measured along different depths, (meters), along a longitudinal sampling course starting
off the shelf in the Pacific Ocean with station #2 and moving towards station #7 at the top of Admiralty Inlet.
DO levels in depths deeper than 31 meters increased closer in shore and further into Puget Sound. In contrast, surface
DO levels, (< 31 meters), dropped at the shelf break to the top of Admiralty Inlet (Figure 2).
Fluorescence and Chlorophyll
Comparing the CTD fluorescence and fluorometer measurements from 20 stations resulted in a R2=0.8156 taking away four
outliers (Figure 3).
Figure 3. Results from the CTD and fluorometer methods compared.
Each station produced similar results for both test methods per depth. The highest measured fluorescence
and chlorophyll were within the first 50 meters of the water. Station 6, Shelf Break 2, had the highest fluorescence and Chlorophyll
outside of the straits (Figure 4).
Figure 4. Longitudinal sample course in order from offshore into Puget Sound comparing fluorescence and chlorophyll
averages in 50 meters or less.
Temperature
Temperature followed a general pattern of warmest at the surface and cooling upon descending in depth. Ranges
averaging 8.7°C at the surface down to 2.2°C at around 2300 meters deep off the shelf in the Pacific Ocean. Station 6,
Shelf Break 2, had slightly higher temperature between 11-30 meters deep (Figure 5) than at the surface.
Figure 5. Temperature measured at different depths per station along a longitudinal course from offshore to Tatoosh.
Density and salinity had similar results along the longitudinal sampling course at all depths (Table 1). The highest values were
obtained offshore and at greater depths. Station 6, Shelf Break 2 had lower density and salinity values of 24.144 kg/l m^and
31.233 PSU near the surface compared to other samples outside of Admiralty Inlet and the averages from this study.
| Depth m | Temperature °C | Density kg/l m^ | Salinity PSU | Conductivity us |
| <10 | 8.580 | 24.641 | 31.781 | 33.815 |
| 10-30 | 8.768 | 24.601 | 31.737 | 33.819 |
| 31-65 | 7.679 | 25.664 | 32.889 | 33.979 |
| 66.115 | 7.517 | 25.927 | 33.195 | 34.134 |
| 116-210 | 6.988 | 26.587 | 33.939 | 34.384 |
| 211-360 | 6.092 | 26.762 | 34.009 | 33.710 |
| 750-805 | 6.092 | 26.762 | 34.009 | 33.710 |
| 1450-2300 | 2.192 | 27.634 | 34.573 | 31.425 |
Plankton
The phytoplankton counts were varied amoung the different stations sampled. Station #6, Shelf Break 2, had the highest
phytoplankton count and station #2 had the highest counts of zooplankton (Figure 6).
Of the zooplankton sampled, copepods were the most prevailent.
Figure 6. Plankton counts for stations #2, #3, and #6.
Sediments
Sediments samples taken from stations 2, 3 and 6 had varied sediment results. Station #2, Abyssal Plain, had predominately
coarse sand falling in the 500 micron range. Station #3 resulted in very coarse sand in the 1mm range and station #6 was
predominately 2mm in size, which is very fine pebble gravel.
Nutrients
The highest nitrate and phosphate levels were found in the furthers station from shore at station #2, Abyssal Plain, and at
the deeper depths (Figure 7). From station #2-5, the nutrients decrease and then begin to increase at station #6, Shelf Break 2.
Station #7 shows a spike in the upper 30 meters of the water.
Figure 7. Phosphate levels for stations #2-7.
Figure 8. Nitrate levels for stations #2-7.