Wetlands provide numerous ecosystem services; one of the most valuable services they can provide people is their  natural ability to perform water filtration. I want to understand how connected wetlands are to water quality.

5/14/2014 UPDATE: After much deliberation, I’m taking a different approach to this project and class, and hopefully thesis!

New Research Questions
− Using Finley as a case study, can a wetland refuge improve water quality? To what extent?
a. how can it improve water quality – nutrients – evidence wetlands can act as a nitrogen sink – great in an agriculture heavy area like Corvallis
− How similar or different are invertebrate and plant communities (diversity and abundance as an indication of how “healthy” the ecosystems are) within Finley compared to surrounding streams and mitigated wetlands?
a. R: statistically significant correlations?
b. ArcGIS: spatial relationships (maybe cluster analysis)? (would need to account for spatial autocorrelation of habitat type, etc)
− Historically, how has land use affected the Finley refuge wetlands? How has Finley’s history impacted this study? How may land use affect the wetlands today?

Hypothesis
− ecosystem service of wetlands is improvement in water quality: I hope to show streams leaving wetlands will have a lower quantity of nitrogen than streams entering wetlands
a. may need a lit review: see what improvement is typical and to what extent to have a baseline
– can also compare to other surrounding stream quality data – maybe proximity analysis correlated with change in quality? I expect to see quality, again, improved leaving wetlands than those that don’t interact with the wetlands at all.

– I would expect similar-size nearby mitigated wetlands to show similar results; if different, maybe plant and invert communities can indicate differences in ecosystem health between the refuge and mitigated wetlands.

– I would expect past land use, as well as current surrounding land use, to impact the health of the wetlands and streams – run a land use correlation in comparison to plant communities and nitrogen content of streams?

Also, anyone know of a good land use Shapefile that incorporates the Finley area? Or any other Shapefiles that exist for Finley/surrounding areas? I’d hate to work off of aerial photography if I don’t have to (I’m not familiar with it, so if I do need to go that route any links to tutorials would be great!), any input is appreciated. This is a seed of an idea that can go a lot of ways.

Will update with a map next week!

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A National Wetlands Inventory shapefile of Oregon’s wetlands was clipped to the nine counties that make up the Willamette Valley (county data provided by BLM): Multnomah, Washington, Yamhill, Clackamas, Marion, Polk, Linn, Benton, and Lane Counties. Using wetlands mapped between 1994 and 1996 by  The Nature Conservancy of Oregon (funded by the Willamette Basin Geographic Initiative Program and the Environmental Protection Agency (EPA)), data was created that inventoried, classified, and mapped native wetland and riparian plant communities and their threatened biota in the Willamette Valley. I have also clipped 2004 – 2006 stream and lake water quality data from the DEQ to these counties. Furthermore, I have mitigation bank data compiled by ODSL and ODOT developed by The Nature Conservancy of mitigated wetland locations in the Willamette Valley.

I am interested in looking at connectivity of streams to wetlands and the relationship of water quality to wetland location. For connectivity I may compare streams connected to wetlands versus those that are not connected to wetlands. Additionally, I am interested in seeing if the water quality data is different around mitigated wetlands versus natural wetlands. I also have stream and lake water quality data from other years, so measuring statistically significant change over time as well.

I am interested in receiving comments regarding potential statistical analyses to examine connectivity; to compare water quality around mitigated versus natural wetlands; and comparing water quality data over time.