University of Illinois Urbana-Champaign

Linking soil respiration to hydrologic conditions and climate change

Liu, Yuchen

Content Files
LIU-DISSERTATION-2020.pdf

Permalink

https://hdl.handle.net/2142/108124

Description

Title
Linking soil respiration to hydrologic conditions and climate change
Author(s)
Liu, Yuchen
Issue Date
2020-05-04
Director of Research (if dissertation) or Advisor (if thesis)
Druhan, Jennifer L
Doctoral Committee Chair(s)
Druhan, Jennifer L
Committee Member(s)
  • Johnson, Thomas M
  • Sanford, Robert A
  • Kumar, Praveen
Department of Study
Geology
Discipline
Geology
Degree Granting Institution
University of Illinois at Urbana-Champaign
Degree Name
Ph.D.
Degree Level
Dissertation
Date of Ingest
2020-08-26T23:55:54Z
Keyword(s)
  • Soil respiration
  • Reactive transport model
  • Soil incubation
Abstract
Respiration of organic carbon in soils is one of the largest terrestrial sources of atmospheric CO2 and shifts in the rate of this flux poses one of the largest potential impacts on global warming. Previous studies have found that temperature and soil moisture contents exert first order controls on soil carbon respiration rate using both laboratory incubation experiments and field measurements, however, extrapolations from the respiration rates measured for specific soil samples to environmental systems are still challenged. Multiple mechanisms have been proposed to create the relationship between these environmental factors and soil respiration rate. Yet the application of such mechanisms into high-performance reactive transport frameworks is sparse and incomplete, and thus currently limits cross-field interpolations. To fill in these gaps, I have established a novel process-based reactive transport framework incorporating the transition between active and dormant biomass as a function of soil moisture, to improve the accuracy of model simulations in reproducing data collected from both incubation experiment and the field. This advanced model is applied to both paleo-studies as a means of more accurately reconstructing past atmospheric CO2 concentration variations, and interpolations to evaluate future climate changes. By comparing the common behavior observed in incubation experiments using sparsely sampled soils and a compiled dataset including 436 incubation datasets collected across the globe, this work further guides the spatial upscaling of current numerical simulations.
Graduation Semester
2020-05
Type of Resource
Thesis
Permalink
http://hdl.handle.net/2142/108124
Copyright and License Information
Copyright 2020 Yuchen Liu

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