title: Impact of catchment geophysical characteristics and climate on the regional variability of dissolved organic carbon (DOC) in surface water.
abstract: Dissolved organic carbon (DOC) is a recognized indicator of natural organic matter (NOM) in surface waters. The aim of this paper is twofold: to evaluate the impact of geophysical characteristics, climate and ecological zones on DOC concentrations in surface waters and, to develop a statistical model to estimate the regional variability of these concentrations. In this study, multilevel statistical analysis was used to achieve three specific objectives: (1) evaluate the influence of climate and geophysical characteristics on DOC concentrations in surface waters; (2) compare the influence of geophysical characteristics and ecological zones on DOC concentrations in surface waters; and (3) develop a model to estimate the most accurate DOC concentrations in surface waters. The case study involved 115 catchments from surface waters in the Province of Quebec, Canada. Results showed that mean temperatures recorded 60 days prior to sampling, total precipitation 10 days prior to sampling and percentages of wetlands, coniferous forests and mixed forests have a significant positive influence on DOC concentrations in surface waters. The catchment mean slope had a significant negative influence on DOC concentrations in surface waters. Water type (lake or river) and deciduous forest variables were not significant. The ecological zones had a significant influence on DOC concentrations. However, geophysical characteristics (wetlands, forests and slope) estimated DOC concentrations more accurately. A model describing the variability of DOC concentrations was developed and can be used, in future research, for estimating DBPs in drinking water as well evaluating the impact of climate change on the quality of surface waters and drinking water.
authors.affiliation: École supérieure d'aménagement du territoire et développement régional, Université Laval, 1624 Pavillon F.A. Savard, Université Laval, Québec, Qc, Canada. Electronic address: genevieve.cool@crad.ulaval.ca.
authors.forename: Geneviève
authors.initials: G
authors.lastname: Cool
authors.affiliation: École supérieure d'aménagement du territoire et développement régional, Université Laval, 1624 Pavillon F.A. Savard, Université Laval, Québec, Qc, Canada. Electronic address: alexandre.lebel@esad.ulaval.ca.
authors.forename: Alexandre
authors.initials: A
authors.lastname: Lebel
authors.affiliation: School of Engineering, University of British-Columbia - Okanagan, Canada. Electronic address: rehan.sadiq@ubc.ca.
authors.forename: Rehan
authors.initials: R
authors.lastname: Sadiq
authors.affiliation: École supérieure d'aménagement du territoire et développement régional, Université Laval, 1624 Pavillon F.A. Savard, Université Laval, Québec, Qc, Canada. Electronic address: manuel.rodriguez@esad.ulaval.ca.
authors.forename: Manuel J
authors.initials: MJ
authors.lastname: Rodriguez
mesh_terms: D002244:Carbon / Q000032:analysis*; D057231:Climate Change; D004784:Environmental Monitoring; D005618:Fresh Water / Q000737:chemistry*; D011792:Quebec; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D014874:Water Pollutants, Chemical; D002244:Carbon
keywords: Dissolved organic carbon; Multilevel analysis; Surface water