Summary

While stratification was observed in the Strait of Juan de Fuca, a freshwater layer from the Fraser River was not observed in our sampling. In order to gain a more complex knowledge of this system, sampling in the Georgia Strait is suggested. This would allow for the observation of freshwater input prior to mixing in the San Juan Channel.

Due to weak stratification in the San Juan Channel, nutrients are able to diffuse readily through the water column, which has wide implications for aquatic organisms. Higher densities of phytoplankton were observed in the San Juan channel verses Juan de Fuca Strait which displays greater stratification.This reinforces the inability of a weak thermocline to obstruct nutrient diffusion from deeper waters as phytoplankton growth is dependent upon these nutrients. Also, biologic productivity indicated adequate flushing of the areas sampled. However, smaller more protected bays should be studied to determine flushing and circulation patterns as well.

As a whole, this field experience was beneficial in gaining a greater understanding of the physical forces and biological productivity occuring in the San Juan Channel. Even though these waters are currently "pristine", as the population of the San Juan Islands continue to increase monitoring of dissolved oxygen, nutrient levels and biological productivity becomes increasingly important and areas with slow flushing times will be the most susceptible to pollution.

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