A Study on the Impact of Current Speed on Micro-plastic Concentration

• Main Author: Ball, Katherine
• Format: Text
• Language: English
• Published: Western CEDAR 2014
• Subjects: Terrestrial and Aquatic Ecology; Northeast Arm; Orca
• Online Access: https://cedar.wwu.edu/ssec/2014ssec/Day2/1

The estuarine factors that influence density stratification (riverine input and tidal exchange) in Possession Sound, located in the northeast arm of the Whidbey Basin, also influence the distribution of anthropogenic plastics. Research by the National Oceanic and Atmospheric Administration (NOAA) demonstrated that plastics collect at the surface of the water column and in the sediments. Undergraduate researchers at the Ocean Research College Academy (ORCA), an early college program through Everett Community College, sampled the surface of the water column for microplastics in the spring of 2013. Their research showed higher current speeds and lower plastic concentrations in the center of Possession Sound and higher plastics concentrations near shore at the Mukilteo ferry terminal. Additional research seeks further confirmation of the influence of current speed and location on the distribution of plastics in Possession Sound. Surface collections were conducted at two public access docks on opposite sides of Possession Sound (Everett, WA and Langley, WA). Samples were collected using a 20 μm plankton net in spring, fall, and winter of 2013. Water samples will be analyzed for plastics through a chemical density separation in winter 2014. It is hypothesized that slower current speeds will correlate with higher plastic levels because the plastics are transferred through the area at a slower rate, therefore collecting in that location. Therefore the Langley sampling site should have the highest concentrations of microplastics due to its protected location in a cove.