{"id":{"repo_id":"vt","oai_identifier":"oai:vtechworks.lib.vt.edu:10919/50975"},"canonical_url":"https://search.dev.ndltd.org/etd/vt/oai:vtechworks.lib.vt.edu:10919/50975","repository":{"repo_id":"vt","name":"Virginia Tech","base_url":"https://vtechworks.lib.vt.edu/oai/request"},"display":{"title":"Nitrogen release, tree uptake, and ecosystem retention in a mid-rotation loblolly pine plantation following fertilization with 15N-enriched enhanced efficiency fertilizers","abstract":"Nitrogen is the most frequently limiting nutrient in southern pine plantations. Previous studies found that only 10 to 25% of applied urea fertilizer N is taken up by trees. Enhanced efficiency fertilizers could increase tree uptake efficiency by controlling the release of N and/or stabilize N. Three enhanced efficiency fertilizers were selected as a representation of fertilizers that could be used in forestry: 1) NBPT treated urea (NBPT urea), 2) polymer coated urea (PC urea), and 3) monoammonium phosphate coated NBPT treated urea (MC NBPT urea). Urea, MC NBPT urea, and NBPT urea fertilizer treatments showed an extractable NH4+ spike 14 days after fertilization while the polymer coated urea showed a spike in NH4+ 49 days after fertilization. Total ecosystem recovery of fertilizer in each treatment was; MC NBPT urea, 51.29 g N; NBPT urea, 48.87 g N; urea, 45.09 g N; and PC urea, 31.30 g N which represents 78.7%, 74.7%, 72.1%, and 47.6% respectively of the total N applied. For the MC NBPT urea, NBPT urea, and PC urea treatments the largest sinks for N were the forest floor and mineral soil. The largest sink for fertilizer applied N in the urea treatment was in the tree. The 2011 foliage cohort was the largest sinks for fertilizer N recovered by the tree. N volatilization was around 20% for all fertilizer treatments except polymer coated fertilizer, which was 1.1%. Urea preformed the same as the soluble enhanced efficiency fertilizers and better than the PC urea fertilizer. The results emphasize the importance of climatic conditions on fertilizer release and effectiveness.","abstract_html":"Nitrogen is the most frequently limiting nutrient in southern pine plantations. Previous studies found that only 10 to 25% of applied urea fertilizer N is taken up by trees. Enhanced efficiency fertilizers could increase tree uptake efficiency by controlling the release of N and/or stabilize N. Three enhanced efficiency fertilizers were selected as a representation of fertilizers that could be used in forestry: 1) NBPT treated urea (NBPT urea), 2) polymer coated urea (PC urea), and 3) monoammonium phosphate coated NBPT treated urea (MC NBPT urea). Urea, MC NBPT urea, and NBPT urea fertilizer treatments showed an extractable NH4+ spike 14 days after fertilization while the polymer coated urea showed a spike in NH4+ 49 days after fertilization. Total ecosystem recovery of fertilizer in each treatment was; MC NBPT urea, 51.29 g N; NBPT urea, 48.87 g N; urea, 45.09 g N; and PC urea, 31.30 g N which represents 78.7%, 74.7%, 72.1%, and 47.6% respectively of the total N applied. For the MC NBPT urea, NBPT urea, and PC urea treatments the largest sinks for N were the forest floor and mineral soil. The largest sink for fertilizer applied N in the urea treatment was in the tree. The 2011 foliage cohort was the largest sinks for fertilizer N recovered by the tree. N volatilization was around 20% for all fertilizer treatments except polymer coated fertilizer, which was 1.1%. Urea preformed the same as the soluble enhanced efficiency fertilizers and better than the PC urea fertilizer. The results emphasize the importance of climatic conditions on fertilizer release and effectiveness.","abstract_has_math":false,"creators":["Werner, Amy"],"institution":"Virginia Tech","degree_name":"Master of Science","degree_level":"masters","degree_discipline":"Forestry","degree_department":"Forest Resources and Environmental Conservation","school":null,"contributors":[],"advisors":[],"committee_chairs":["Fox, Thomas R."],"committee_members":["Seiler, John R.","Strahm, Brian D."],"year":2013,"date_issued":"2013-06-11","date_published":"2013-06-11","updated_at":"2026-07-22T22:19:53Z","subjects":["enhanced efficiency fertilizer","15N","stable isotope","Loblolly pine"],"languages":[],"rights":["In Copyright"],"rights_urls":["http://rightsstatements.org/vocab/InC/1.0/"],"identifier_entries":[{"key":"dc:identifier.other","label":"Dc Identifier Other","values":["vt_gsexam:1229"],"render_values":[{"text":"vt_gsexam:1229","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/10919/50975","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.committeechair","label":"Committee Chair","values":["Fox, Thomas R."]},{"key":"dc:contributor.committeemember","label":"Committee Member","values":["Seiler, John R.","Strahm, Brian D."]},{"key":"dc:contributor.department","label":"Department","values":["Forest Resources and Environmental Conservation"]},{"key":"dc:creator","label":"Author","values":["Werner, Amy"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2014-12-04T07:01:58Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2014-12-04T07:01:58Z"]},{"key":"dc:date.issued","label":"Date","values":["2013-06-11"]},{"key":"dc:publisher","label":"Institution","values":["Virginia Tech"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Forestry"]},{"key":"thesis:degree_level","label":"Degree Level","values":["masters"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master of Science"]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["Virginia Polytechnic Institute and State University"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["enhanced efficiency fertilizer","15N","stable isotope","Loblolly pine"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:rights","label":"Dc Rights","values":["In Copyright"]},{"key":"dc:rights.uri","label":"Rights URI","values":["http://rightsstatements.org/vocab/InC/1.0/"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.other","label":"Dc Identifier Other","values":["vt_gsexam:1229"]},{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/10919/50975"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Nitrogen is the most frequently limiting nutrient in southern pine plantations. Previous studies found that only 10 to 25% of applied urea fertilizer N is taken up by trees. Enhanced efficiency fertilizers could increase tree uptake efficiency by controlling the release of N and/or stabilize N. Three enhanced efficiency fertilizers were selected as a representation of fertilizers that could be used in forestry: 1) NBPT treated urea (NBPT urea), 2) polymer coated urea (PC urea), and 3) monoammonium phosphate coated NBPT treated urea (MC NBPT urea). Urea, MC NBPT urea, and NBPT urea fertilizer treatments showed an extractable NH4+ spike 14 days after fertilization while the polymer coated urea showed a spike in NH4+ 49 days after fertilization. Total ecosystem recovery of fertilizer in each treatment was; MC NBPT urea, 51.29 g N; NBPT urea, 48.87 g N; urea, 45.09 g N; and PC urea, 31.30 g N which represents 78.7%, 74.7%, 72.1%, and 47.6% respectively of the total N applied. For the MC NBPT urea, NBPT urea, and PC urea treatments the largest sinks for N were the forest floor and mineral soil. The largest sink for fertilizer applied N in the urea treatment was in the tree. The 2011 foliage cohort was the largest sinks for fertilizer N recovered by the tree. N volatilization was around 20% for all fertilizer treatments except polymer coated fertilizer, which was 1.1%. Urea preformed the same as the soluble enhanced efficiency fertilizers and better than the PC urea fertilizer. The results emphasize the importance of climatic conditions on fertilizer release and effectiveness."]},{"key":"dc:description.degree","label":"Dc Description Degree","values":["Master of Science"]},{"key":"dc:format.medium","label":"Dc Format Medium","values":["ETD"]},{"key":"dc:title","label":"Title","values":["Nitrogen release, tree uptake, and ecosystem retention in a mid-rotation loblolly pine plantation following fertilization with 15N-enriched enhanced efficiency fertilizers"]}]}],"canonical_facts":{"dc:contributor.committeechair":["Fox, Thomas R."],"dc:contributor.committeemember":["Seiler, John R.","Strahm, Brian D."],"dc:contributor.department":["Forest Resources and Environmental Conservation"],"dc:creator":["Werner, Amy"],"dc:date.accessioned":["2014-12-04T07:01:58Z"],"dc:date.available":["2014-12-04T07:01:58Z"],"dc:date.issued":["2013-06-11"],"dc:description.abstract":["Nitrogen is the most frequently limiting nutrient in southern pine plantations. Previous studies found that only 10 to 25% of applied urea fertilizer N is taken up by trees. Enhanced efficiency fertilizers could increase tree uptake efficiency by controlling the release of N and/or stabilize N. Three enhanced efficiency fertilizers were selected as a representation of fertilizers that could be used in forestry: 1) NBPT treated urea (NBPT urea), 2) polymer coated urea (PC urea), and 3) monoammonium phosphate coated NBPT treated urea (MC NBPT urea). Urea, MC NBPT urea, and NBPT urea fertilizer treatments showed an extractable NH4+ spike 14 days after fertilization while the polymer coated urea showed a spike in NH4+ 49 days after fertilization. Total ecosystem recovery of fertilizer in each treatment was; MC NBPT urea, 51.29 g N; NBPT urea, 48.87 g N; urea, 45.09 g N; and PC urea, 31.30 g N which represents 78.7%, 74.7%, 72.1%, and 47.6% respectively of the total N applied. For the MC NBPT urea, NBPT urea, and PC urea treatments the largest sinks for N were the forest floor and mineral soil. The largest sink for fertilizer applied N in the urea treatment was in the tree. The 2011 foliage cohort was the largest sinks for fertilizer N recovered by the tree. N volatilization was around 20% for all fertilizer treatments except polymer coated fertilizer, which was 1.1%. Urea preformed the same as the soluble enhanced efficiency fertilizers and better than the PC urea fertilizer. The results emphasize the importance of climatic conditions on fertilizer release and effectiveness."],"dc:description.degree":["Master of Science"],"dc:format.medium":["ETD"],"dc:identifier.other":["vt_gsexam:1229"],"dc:identifier.uri":["http://hdl.handle.net/10919/50975"],"dc:publisher":["Virginia Tech"],"dc:rights":["In Copyright"],"dc:rights.uri":["http://rightsstatements.org/vocab/InC/1.0/"],"dc:subject":["enhanced efficiency fertilizer","15N","stable isotope","Loblolly pine"],"dc:title":["Nitrogen release, tree uptake, and ecosystem retention in a mid-rotation loblolly pine plantation following fertilization with 15N-enriched enhanced efficiency fertilizers"],"dc:type":["Thesis"],"thesis:degree_discipline":["Forestry"],"thesis:degree_level":["masters"],"thesis:degree_name":["Master of Science"],"thesis:institution_name":["Virginia Polytechnic Institute and State University"]},"updated_at":"2026-07-22T22:19:53Z"}