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dc.contributor.authorPinney, Jenae Elizabethen_US
dc.date.accessioned2017-04-04T19:49:20Z
dc.date.available2017-04-04T19:49:20Z
dc.date.issued2011-05-27en_US
dc.identifier.otheretd-06192011-172727en_US
dc.identifier.urihttp://hdl.handle.net/10919/76801
dc.description.abstractThe sediment-water interface is an active biogeochemical zone within streams, where solutes come in contact with mineral surfaces, biota, and reducing conditions. Here, we sought to examine the influence of light, the sediment water interface, and algae on dissolved organic carbon (DOC), nitrogen, and phosphorus within Maple Creek, an agriculturally impacted stream located in Fremont, Nebraska. Simultaneous continuous injection experiments into replicate open- and closed-bottom chambers were used to control the hydrologic residence time. A bromide tracer was injected, and samples were taken for nutrient analysis in the surface and subsurface water at depths up to 8 cm. Dissolved oxygen (DO) and temperature were recorded in order to monitor biotic production. Experiments were conducted over 10 hours, encompassing both light and dark conditions. Results show a strong biotic influence at the sediment-water interface causing nutrient uptake and changes in carbon quality. Changes are especially pronounced during peak photosynthesis hours. The open-bottom mesocosms consistently showed removal of N and P from the surface water to the subsurface. An increase in DOC flux was observed in the open-bottom mesocosms and the organic matter pool exhibited evidence of microbial reduction. The closed-bottom mesocosm showed NH?⁺ increased likely due to photochemical oxidation. These results show the importance of promoting exchange through the subsurface and across the sediment-water interface due to the positive impact it has on nutrient retention.
dc.language.isoen_USen_US
dc.publisherVirginia Techen_US
dc.rightsI hereby certify that, if appropriate, I have obtained and attached hereto a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted is the same as that approved by my advisory committee. I hereby grant to Virginia Tech or its agents the non-exclusive license to archive and make accessible, under the conditions specified below, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report.en_US
dc.subjectDOMen_US
dc.subjectAmmoniumen_US
dc.subjectPhosphorusen_US
dc.subjectNitrateen_US
dc.subjectNutrient Retentionen_US
dc.titleInfluence of light and algae on nutrient transformations at the sediment-water interface of an agricultural streamen_US
dc.typeThesisen_US
dc.contributor.departmentBiological Systems Engineeringen_US
dc.description.degreeMaster of Engineeringen_US
thesis.degree.nameMaster of Engineeringen_US
thesis.degree.levelmastersen_US
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen_US
dc.contributor.committeechairScott, Durelleen_US
dc.contributor.committeememberGallagher, Daniel L.en_US
dc.contributor.committeememberHession, William Cullyen_US
dc.type.dcmitypeTexten_US
dc.identifier.sourceurlhttp://theses.lib.vt.edu/theses/available/etd-06192011-172727/en_US
dc.date.sdate2011-06-19en_US
dc.date.rdate2016-10-17
dc.date.adate2011-07-14en_US


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