Results/Discussion:

All the following sections are shown first at a deep profile followed by a shallow profile.

Temperature (degrees celcius): The range of the temperature of water is dependant on its clarity, its concentration of debris, and the amount of mixture that is allowed by the system. Quartermaster Harbor has some unique topography and bathymetry that affects its flushing rate and what processes go on there; including temperature. Station 1 is by far the shallowest station at seven meters and is also tucked away which allows it to hold its water supply for a longer period of time than the other stations tested. At 11.6 degrees C even at the beginning of the day makes it the warmest station tested. Stations 2 and 4 were similar although station 2 was would probably had been warmer than station 4 if we had tested them closer together because station 2 is much shallower in addition to the fact that it is not as free flowing as station 4. Station 3 was much lower in temperature than the other inward stations probably because the area surrounding it is much wider, allowing for more movement. Station 5 has a very slight, gradual change in temperature. From top to the thirty meter mark the station only recorded a .8 degree change in temperature and only a 1.5 degree change form top to bottom. This means that station 5 is well mixed and is not as affected by temperature changes as the more inward, shallow stations are.

Salinity (PSU): Stations 1 through 4 did not show a wide change in salinity top to bottom. This is because there is not a lot of mixing because the harbor is fairly well protected, narrow and shallow. Station 5 however shows quite a large halocline of almost a whole mark within less than a five meter area. This is because station 5 is near the middle of Commencement Bay therefore it is more affected by the inflow of fresh water form the Puyallup River and other tributaries that spill into the bay. Since the less dense fresh water will tend to sit on top of the more dense salt water they do not mix well and therefore a halocline is formed.

Density (kilograms/m^3): The density graph looks much like the salinity graph; this is because waters density is dependant upon the amount of salinity that is a part of the system; among other things such as temperature. It is quite similar especially when you look at station 5 and notice the same trend as in the salinity graph concerning the halocline.

Dissolved Oxygen (ml/liter): The dissolved oxygen does show more of a trend towards the natural progression of the water way then some of the other plots do. Station 1 of course has the highest amount of dissolved oxygen because it has the highest concentration of phytoplankton of any of the site, about 10 ml/l. This, again, is because station 1 is more protected than the other stations and is not flushed as regularly as the others are. There is a slight progression there on toward the lowest record at station 5, about 6.5 ml/l. This is to be expected because plankton are more abundant where there is more nutrients and inside Quartermaster harbor there is much more nutrient due to septic systems and runoff rather than nearer the middle of Commencement Bay.

The above laboratory dissolved oxygen graph shows oxygen levels decrease with increasing depths. The second station 5 - (1meter) depth calculation seems to show a great error. Also, this graph shows station 2 as having higher levels of dissolved oxygen when compared to station 1. This does not correlate with the chlorophyll graph that shows station 1 having a greater amount of chlorophyll, which normally increases O2 levels. However, the graph does show station 1 as having higher D.O levels than station 5, which corelates with the below phytoplankton graph showing higher primary productivity at station 1. The high dissolved oxygen levels provide plenty of dissolved oxygen to the herring fish who use this area as a hatching ground.

The CTD results vary considerably for station 1 and 2 compared to the laboratory results for D.O. levels. During this course, students rotated laboratory tasks each field study to obtain hands on experience with all the equipment. Because of the learning curve, the laboratory data are off from the CTD data.

Chlorophyll (mg/m^3): This data is a bit more curious than the other sets because it look to be all over the place; at least near the middle of the harbor. Station 1 would be expected to have the highest value since it has the highest volume of phytoplankton but station 3 has the most; 87.7 mg/m^3 where as station 1 has the second highest concentration at 72.3 mg/m^3. Station 2 and 4 follow suit as in the rest of the charts with station 5 again holding the lowest value with its highest reaching point being only 12.3 mg/m^3. the only thing that seems out of place here is that station 1 and 3 are reversed, everything else seems to be in order with the rest of the information gathered.

The laboratory results of chlorophyll levels agree with the phytoplankton graph of diatom levels shown below. Each graph shows that station 1 has the greatest concentrations of phytoplankton as well as the highest levels of chlorophyll. The overall trend of the chlorophyll graph shows phytoplankton levels decreasing southward in respect to inner quartermaster harbor. The reasons for this are the same as mentioned in the D.O. discussion, such as weaker currents, greater levels of stratification and possible high nutrient levels due to its secluded location.
As stated earlier, during this course students rotated laboratory tasks each field study to obtain hands on experience with all the equipment. Because of the learning curve, the laboratory data are off from the CTD data.

Light Transmission (%): Station 1 has the lowest light transmission level, 44.9 %, because of all of the plankton that is concentrated at that point. Station 5 is again the opposite of station 1 with its lowest value of 80.7 %. This again is because station 5's location allows it to mix well and move out impurities where as station 1 is fairly stagnant and does not mix well at all. The other stations follow in line from 2 to 4 because of their varied abilities to flush and mix.

Phytoplankton Counts

The Puget Sound is an estuary of very high productivity. In comparison, the average productivity of the Pacific Ocean is 120 gC/M^2/Yr, where as the productivity of the Puget Sound is 460 gC/M^2/Yr. The trophic efficiency of the Puget Sound is at best 20%. Diatoms, which are pillbox in shape, and can connect in long chains, are the main organisms that form the base of the food chain for Puget Sound. These organisms are photosynthetic primary producers. Diatoms have very high levels of primary productivity, and can quickly convert energy to glucose.

The above data show that centric diatoms dominate the phytoplankton populations in quartermaster harbor for stations 1 and 5, and that centric diatoms account for the greatest number of phytoplankton at station 3. It is also interesting to note that station #1 which is in the inner Quartermaster Harbor area shows the highest plankton count, thus highest productivity. Station #5, which is out towards the main basin, and subject to more intense currents and mixing, shows the lowest level of productivity for QMH. The high levels of phytoplankton at station 1 could be due to a number of factors including:

a) Increased stratification being surrounded by land and away from the mouth of QMH to the south
b) Possible nutrient pollution from the area, although this is just speculation
c) And something that ties into b, the fact that there is a greater residence time due to the weak currents in this area, which will also allow for greater populations of phytoplankton to propagate.

The above graphs show the current speed in cm/sec along with the direction of the currents at stations 1 through 4. The general trend of the data is that the currents increase as one moves southward towards the mouth of QMH. However, station 2 has an especially strong current for its location relatively northward. This is due to the current that runs between Burton Peninsula and Raab's Lagoon. The above tidal level graph above shows that at 1:06pm, the time at which station 4 data was collected, there was an ebb tide. This means the current direction would be southward as water moves out from the southern entrence to QMH. The directional data for station 4 showing a southward current correlates with the data.

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