Stratification Influences on Instream Carbon Chemistry and Export within a Beaded Arctic Stream and Evaluation of Fluorescence Instrumentation ...

• Main Author: Harrold, Katherine H.
• Format: Thesis
• Language: English
• Published: University of North Carolina at Chapel Hill 2013
• Subjects: Arctic
• Online Access: https://dx.doi.org/10.17615/fyzw-yd75; https://cdr.lib.unc.edu/concern/dissertations/q811kk61p?locale=en

I investigated the effect of stratification in beaded stream pools on the quantity and quality of dissolved organic matter (DOM). Soil waters feeding the pool bottom waters overlapped in chromophoric (CDOM) and fluorescent (FDOM) quantity and quality, while pool surface waters had on average 56 and 32 % less CDOM and FDOM, respectively, compared to pool bottom waters. The observed differences between pool surface and bottom waters were consistent with shifts in CDOM and FDOM following experimental photodegradation of pool bottom waters. To improve FDOM characterization across time and instruments, FDOM analysis was evaluated using the Aqualog, a new instrument optimized for FDOM, and the Fluoromax-4, a conventional spectrofluorometer, across a range of CDOM and FDOM concentrations. While the application of an empirical inter-instrument correction factor improved the inter-instrument FDOM comparison, inter-instrument variability was not fully removed by application of a range of correction factors. ...