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dc.contributor.supervisorKuzyk, Zou Zou (Environment and Geography) Ehn, Jens (Environment and Geography)en_US
dc.contributor.authorGuzzi, Alessia
dc.date.accessioned2022-02-23T03:02:29Z
dc.date.available2022-02-23T03:02:29Z
dc.date.copyright2022-02-09
dc.date.issued2022-02en_US
dc.date.submitted2022-02-10T05:14:07Zen_US
dc.identifier.urihttp://hdl.handle.net/1993/36315
dc.description.abstractIn Arctic marine environments, the renewal of surface nutrient stocks through physical and biogeochemical processes during winter is critical to support primary production later in the season when solar irradiance is sufficient. Landfast sea-ice and river discharge in the riverine coastal domain influence not only the structure of the coastal water column, but also impact the movement and distribution of nutrients within the system. Over the last several decades, both climate change and anthropogenic activities have caused shifts in both sea-ice and riverine cycles. Winter freshwater tracer and nutrient data from Canadian Arctic coastal areas, such as in Hudson Bay are extremely scarce. In this thesis I begin to fill this gap, focusing on three coastal regions: northeast James Bay (NEJB), northwest Hudson Bay (NWHB), and southeast Hudson Bay (SEHB). The objective is to evaluate the relationships between freshwater sources and nutrient distributions, during ice-covered and ice-free seasons, across the selected coastal domains. I present new nutrient (nitrate, phosphate, and silicate) and freshwater tracer (oxygen isotope ratio, salinity) data for water samples collected during ice-covered conditions, and additionally, data from open-water conditions in NEJB. Samples were collected with the help of numerous community members and guides between 2016-2019. Each region was distinct in terms of freshwater composition and influence, with NEJB strongly influenced by La Grande River, as its large under-ice plume (because of regulation) drove surface nutrient concentrations in winter (high nitrate, low phosphate). The sea-ice cycle (withdrawal of freshwater and release of brine during formation) was the dominant influence on NWHB coastal waters. Here there are large concentration ranges of nutrients within a small salinity range, possibly due to an alternate source water, or recirculation of HB outflow. SEHB coastal waters are largely influenced by riverine input from local rivers, and from the upstream James Bay outlet. Nutrient ratios showed potential nitrate limitation at salinities > 10 across all regions. Overall, this thesis provides new data that characterize a multitude of relationships between coastal freshwater sources, marine source waters, and the distribution of nutrients during winter and summer across three oceanographically different coastal regions of Hudson Bay.en_US
dc.language.isoengen_US
dc.rightsinfo:eu-repo/semantics/openAccess
dc.subjectHudson Bayen_US
dc.subjectJames Bayen_US
dc.subjectFreshwateren_US
dc.subjectNutrientsen_US
dc.subjectNitrateen_US
dc.subjectPhosphateen_US
dc.subjectRiverine Coastal Domainen_US
dc.subjectRiver dischargeen_US
dc.subjectLa Grande Riveren_US
dc.titleFreshwater and nutrient distributions in contrasting coastal domains of Hudson Bay and James Bayen_US
dc.typeinfo:eu-repo/semantics/masterThesis
dc.typemaster thesisen_US
dc.degree.disciplineEnvironment and Geographyen_US
dc.contributor.examiningcommitteeMichel, Christine (Environment and Geography)en_US
dc.contributor.examiningcommitteeMacdonald, Robie (Environment and Geography)en_US
dc.degree.levelMaster of Science (M.Sc.)en_US
dc.description.noteMarch 2022en_US


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