{"id":{"repo_id":"york","oai_identifier":"oai:yorkspace.library.yorku.ca:10315/29814"},"canonical_url":"https://search.dev.ndltd.org/etd/york/oai:yorkspace.library.yorku.ca:10315/29814","repository":{"repo_id":"york","name":"York University","base_url":"https://yorkspace.library.yorku.ca/oai/request"},"display":{"title":"Aromatic Rich Natural Organic Matter Increases Growth and Reduces Nickel Toxicity in a Wild Daphnia Hybrid","abstract":"Natural organic matter (NOM) is on the rise across the Shield. Its heterogeneous, amalgamate nature makes each NOM source potentially unique. Relatively little is known about the direct effects distinct NOM sources have on daphniids, or the varying protection NOM provides against metal toxicity –specifically Ni. I show that NOM from different natural sources increases growth rates and decreases time to maturation of Daphnia to various degrees. These changes relate to aromatic content of NOM isolates, the mechanism most likely being a hormonal effect or mild oxidative stress. Aromatic content (representing phenolic groups) is also positively related to Ni mitigation for those isolates with specific UV absorbance below 19.3 cm2mg-1. Incorporating NOM aromatic content into a predictive model improves the relationship between predicted and measured LC50s by 5%. I demonstrate that structural differences between NOM isolates relating to aromatic content play a major role in their effects on Daphnia.","abstract_html":"Natural organic matter (NOM) is on the rise across the Shield. Its heterogeneous, amalgamate nature makes each NOM source potentially unique. Relatively little is known about the direct effects distinct NOM sources have on daphniids, or the varying protection NOM provides against metal toxicity –specifically Ni. I show that NOM from different natural sources increases growth rates and decreases time to maturation of Daphnia to various degrees. These changes relate to aromatic content of NOM isolates, the mechanism most likely being a hormonal effect or mild oxidative stress. Aromatic content (representing phenolic groups) is also positively related to Ni mitigation for those isolates with specific UV absorbance below 19.3 cm2mg-1. Incorporating NOM aromatic content into a predictive model improves the relationship between predicted and measured LC50s by 5%. I demonstrate that structural differences between NOM isolates relating to aromatic content play a major role in their effects on Daphnia.","abstract_has_math":false,"creators":["Geiger, Christine Simone"],"institution":null,"degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":["Yan, Norman","Arts, Michael"],"committee_chairs":[],"committee_members":[],"year":2015,"date_issued":"2015-08-28","date_published":"2015-08-28","updated_at":"2026-07-24T06:33:51Z","subjects":["Limnology","Toxicology","Ecology"],"languages":["en"],"rights":["Author owns copyright, except where explicitly noted. Please contact the author directly with licensing requests."],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/10315/29814","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Yan, Norman","Arts, Michael"]},{"key":"dc:creator","label":"Author","values":["Geiger, Christine Simone"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2015-08-28T14:37:05Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2015-08-28T14:37:05Z"]},{"key":"dc:date.issued","label":"Date","values":["2015-08-28"]},{"key":"dc:type","label":"Dc Type","values":["Electronic Thesis or Dissertation"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Limnology","Toxicology","Ecology"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["en"]},{"key":"dc:rights","label":"Dc Rights","values":["Author owns copyright, except where explicitly noted. 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Aromatic content (representing phenolic groups) is also positively related to Ni mitigation for those isolates with specific UV absorbance below 19.3 cm2mg-1. Incorporating NOM aromatic content into a predictive model improves the relationship between predicted and measured LC50s by 5%. I demonstrate that structural differences between NOM isolates relating to aromatic content play a major role in their effects on Daphnia."]},{"key":"dc:title","label":"Title","values":["Aromatic Rich Natural Organic Matter Increases Growth and Reduces Nickel Toxicity in a Wild Daphnia Hybrid"]}]}],"canonical_facts":{"dc:contributor.advisor":["Yan, Norman","Arts, Michael"],"dc:creator":["Geiger, Christine Simone"],"dc:date.accessioned":["2015-08-28T14:37:05Z"],"dc:date.available":["2015-08-28T14:37:05Z"],"dc:date.issued":["2015-08-28"],"dc:description.abstract":["Natural organic matter (NOM) is on the rise across the Shield. Its heterogeneous, amalgamate nature makes each NOM source potentially unique. Relatively little is known about the direct effects distinct NOM sources have on daphniids, or the varying protection NOM provides against metal toxicity –specifically Ni. I show that NOM from different natural sources increases growth rates and decreases time to maturation of Daphnia to various degrees. These changes relate to aromatic content of NOM isolates, the mechanism most likely being a hormonal effect or mild oxidative stress. Aromatic content (representing phenolic groups) is also positively related to Ni mitigation for those isolates with specific UV absorbance below 19.3 cm2mg-1. Incorporating NOM aromatic content into a predictive model improves the relationship between predicted and measured LC50s by 5%. I demonstrate that structural differences between NOM isolates relating to aromatic content play a major role in their effects on Daphnia."],"dc:identifier.uri":["http://hdl.handle.net/10315/29814"],"dc:language.iso":["en"],"dc:rights":["Author owns copyright, except where explicitly noted. Please contact the author directly with licensing requests."],"dc:subject":["Limnology","Toxicology","Ecology"],"dc:title":["Aromatic Rich Natural Organic Matter Increases Growth and Reduces Nickel Toxicity in a Wild Daphnia Hybrid"],"dc:type":["Electronic Thesis or Dissertation"]},"updated_at":"2026-07-24T06:33:51Z"}