2023 Early Hearing Detection & Intervention Conference
March 5-7, 2023 • Cincinnati, OH
6/05/2017 | 2:15 PM - 2:30 PM | GLOBAL BOUNDS ON GASEOUS NITROGEN LOSS FROM TROPICAL FOREST WATERSHEDS | 306A
GLOBAL BOUNDS ON GASEOUS NITROGEN LOSS FROM TROPICAL FOREST WATERSHEDS
Humid tropical forests dominate denitrification from unmanaged lands, but there is large uncertainty about the range and drivers of N gas emissions across the biome. We combined pantropical measures of stream chemistry with ecosystem modeling to determine total N gas losses and associated uncertainty across tropical forest watersheds. We document a negative relationship between nitrate and dissolved organic carbon (DOC) across watersheds and find that the probability of a missing N sink was highest in watersheds with high DOC, consistent with the imprint of dissimilatory nitrate reduction. We find a large range in gaseous fluxes depending on whether denitrification is modeled occurring downstream of terrestrial plant uptake or competing with plant uptake. Combined, denitrification in soils and along soil-to-stream hydrologic flowpaths constitute >45% of total N losses. We place an upper bound on soil denitrification of ~80% of total N losses beyond which tropical plant growth would be compromised. Our simulations indicate that terrestrial soils dominate denitrification but also reveal globally significant levels of gaseous N loss from aquatic environments that are roughly equivalent to inputs via atmospheric deposition.
- C28 Land-Water Interfaces
- C31 Organic Matter Processing
- C10 Biogeochemistry
Presentation:
This presentation has not yet been uploaded.
Handouts:
Handout is not Available
Transcripts:
CART transcripts are NOT YET available, but will be posted shortly after the conference
Presenters/Authors
Jack Brookshire
(), Montana State University, jbrookshire@montana.edu;
ASHA DISCLOSURE:
Financial -
Nonfinancial -
Stefan Gerber
(), University of Florida, sgerber@ufl.edu;
ASHA DISCLOSURE:
Financial -
Nonfinancial -
Steven Thomas
(), School of Natural Resources, University of Nebraska-Lincoln, Lincoln, sthomas5@unl.edu;
ASHA DISCLOSURE:
Financial -
Nonfinancial -