Defense Date

2011

Document Type

Thesis

Degree Name

Master of Science

Department

Biology

First Advisor

Leigh McCallister

Abstract

Fluvial systems have been estimated to transform, transport, or store 2.75 petagrams (Pg) of Organic Carbon (OC) per year. Although approximately 1Pg per year of terrestrial carbon is fluxed to the atmosphere through inland waters, little is known about the factors regulating its eventual ecological fate. 28 day lability incubations were conducted concurrent with the measurement of several environmental parameters including discharge, nutrient concentration, DO13C, and DOC:DON at several sites along Bigelow Brook and the East Branch of the Swift River, Massachusetts. Temporal and spatial variation of DOC, DOC:DON and DO13C were explored. Two distinct DOC consumption rates, short and long term, as well as overall consumption rate (k), were evaluated to determine the interactions with source, quality, and nutrients. Dissolved organic nutrient concentrations significantly increased long term consumption rates but had little effect on short term rates suggesting that short term rate may be tightly coupled to local, in stream, processes. The short term rate was significantly correlated to k. Interestingly, few significant relationships were found between various rate metrics and the source or quality of the DOC. A large recalcitrant DOC pool persisted after the 28 day period suggestive of downstream export of a large fraction of initial DOC pool.

Rights

© The Author

Is Part Of

VCU University Archives

Is Part Of

VCU Theses and Dissertations

Date of Submission

December 2011

Included in

Biology Commons

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