Spatial and temporal variation in natural organic matter quantity and quality across a second growth forested drinking water supply area on Vancouver Island, BC
department or school: Science, Faculty of
department or school: Earth, Ocean and Atmospheric Sciences, Department of
data provider: DSpace
degree campus: UBCV
creator: McSorley, Hannah Jane
issued: 2020-12-24T20:21:02Z
issued: 2020
related degree: Master of Science - MSc
degree grantor: University of British Columbia
description: Most drinking water in Canada originates in forested headwaters, therefore drinking water security is tied to forest management for many communities. Monitoring source water quality is crucial to a multi-barrier approach to clean drinking water. This research established a stream water sampling program across a second-growth forested drinking water supply area (Greater Victoria, British Columbia, Canada) to evaluate spatiotemporal patterns and variance in natural organic matter (NOM). Over sixteen months (October 2018 to February 2020), 426 stream water samples were collected from twelve sites (ranging from 9.6 to 37 km², elevation 215 to 870 m a.s.l) and analyzed for NOM quality (via UV-Vis absorbance) and quantity (as dissolved organic carbon, DOC). Mean sub-basin DOC concentrations ranged from 4.2 ± 1.8 mg/L⁻¹ to 9.9 ± 3.4 mg/L⁻¹ (DOC range 1.64 - 19.1 mg/L⁻¹). Six of the twelve sites in Leech River watershed (~96 km²) were equipped with vertical passive sampling racks to evaluate rising hydrograph limb NOM dynamics. Hydrologic connectivity to terrestrial source pools increased throughout wet seasons and antecedent wetness was important for stream NOM molecular quality, which shifted from predominantly aliphatic in the dry-season to predominantly aromatic in the wet-season. Sample sub-sets were evaluated for drinking water treatability parameters (n = 8) and total metals contents (n = 42). DOC was correlated with several metals (R² values for Hg: 0.99; Al: 0.81; Fe: 0.72; Cu: 0.47; Ba: 0.25; Mn: 0.21), evidence that aqueous NOM is indeed a master variable important for contaminant transport. More than specific UV absorbance (SUVA₂₅₄) or DOC concentration, the spectral absorbance coefficient at 254 nm (SAC254) was well correlated to disinfection byproduct formation-potential (total trihalomethanes, r = 0.9882; and total haloacetic acids, r = 0.9927). Approximately 80% of the time, DOC concentration peaked with stream stage. Random Forest variable importance measur…
aggregated CHO: https://circle.library.ubc.ca/rest/handle/2429/76908
note: Spatial and Temporal Variation in Natural Organic Matter Quantity and Quality Across a Second Growth Forested Drinking Water Supply Area on Vancouver Island, BC by HANNAH JANE MCSORLEY BSc., Vancouver Island University, 2015 A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE in THE FACULTY OF GRADUATE AND POSTDOCTORAL STUDIES (Geological Sciences) THE UNIVERSITY OF BRITISH COLUMBIA (Vancouver) December 2020 © Hannah Jane McSorley, 2020 ii The following individuals certify that they have read, and recommend to the Faculty of Graduate and Postdoctoral Studies for acceptance, the thesis entitled: “Spatial and temporal variation in natural organic matter quantity and quality across a second growth forested drinking water supply area on Vancouver Island, BC” submitted by Hannah J. McSorley in partial fulfillment of the requirements for the degree of Master of Science in Geological Sciences Examining Committee: Mark Johnson, UBC, Earth Ocean & Atmospheric Science Co-supervisor Bill Floyd, Vancouver Island University, Geography Co-supervisor Roger Beckie, UBC, Earth Ocean & Atmospheric Science Additional Examiner iii Abstract Most drinking water in Canada originates in forested headwaters, therefore drinking water security is tied to forest management for many communities. Monitoring source water quality is crucial to a multi-barrier approach to clean drinking water. This research established a stream water sampling program across a second-growth forested drinking water supply area (Greater Victoria, British Columbia, Canada) to evaluate spatiotemporal patterns and variance in natural organic matter (NOM). Over sixteen months (October 2018 to February 2020), 426 stream water samples were collected from twelve sites (ranging from 9.6 to 37 km2, elevation 215 to 870 m a.s.l) and analyzed for NOM quality (via UV-Vis absorbance) and quantity (as dissolved organic carbon, DOC). Mean sub-basin DOC concentrations ranged from 4.2 ± 1.…
has type: Thesis/Dissertation
date issued: 2021-05
is shown at: 10.14288/1.0395411
language: eng
degree discipline: Geological Sciences
provider: Vancouver : University of British Columbia Library
publisher: University of British Columbia
rights: Attribution-NonCommercial-NoDerivatives 4.0 International
rights URI: http://creativecommons.org/licenses/by-nc-nd/4.0/
scholar level: Graduate
type: Text
identifier URI: http://hdl.handle.net/2429/76908