No Cover Image

E-Thesis 495 views 179 downloads

Climate change effects on soil carbon dynamics: CO2 flux from water-repellent and fire-affected soils / CARMEN SANCHEZ-GARCIA

Swansea University Author: CARMEN SANCHEZ-GARCIA

  • Sanchez-Garcia_Carmen_PhD_Thesis_Final_Redacted.pdf

    PDF | Redacted version - open access

    Copyright: The author, Carmen Sánchez-García, 2021.

    Download (4.42MB)

DOI (Published version): 10.23889/SUthesis.57470

Abstract

Climate change is increasing the frequency and intensity of droughts and this is expected to enhance the development of soil water repellency: a very common property of both dry and fire-affected soils. In some regions climate change is also increasing the occurrence and severity of wildfires. Large...

Full description

Published: Swansea 2021
Institution: Swansea University
Degree level: Doctoral
Degree name: Ph.D
Supervisor: Urbanek, Emilia ; Doerr, Stefan
URI: https://cronfa.swan.ac.uk/Record/cronfa57470
Tags: Add Tag
No Tags, Be the first to tag this record!
first_indexed 2021-07-28T15:16:56Z
last_indexed 2021-07-29T03:17:08Z
id cronfa57470
recordtype RisThesis
fullrecord <?xml version="1.0"?><rfc1807><datestamp>2021-07-28T17:27:34.2025179</datestamp><bib-version>v2</bib-version><id>57470</id><entry>2021-07-28</entry><title>Climate change effects on soil carbon dynamics: CO2 flux from water-repellent and fire-affected soils</title><swanseaauthors><author><sid>748ea0454590c4cd0471f2fbdc496e32</sid><firstname>CARMEN</firstname><surname>SANCHEZ-GARCIA</surname><name>CARMEN SANCHEZ-GARCIA</name><active>true</active><ethesisStudent>false</ethesisStudent></author></swanseaauthors><date>2021-07-28</date><abstract>Climate change is increasing the frequency and intensity of droughts and this is expected to enhance the development of soil water repellency: a very common property of both dry and fire-affected soils. In some regions climate change is also increasing the occurrence and severity of wildfires. Large pulses of CO2 flux from soil to the atmosphere caused by heavy rainfall events (i.e. the Birch effect) can contribute substantially to annual C emissions from soils. However, the effect of the first rainfall after a drought on water-repellent soils and the first post-fire rainfall event on soil CO2 flux remain poorly understood. To address these knowledge gaps this research focuses on: i) investigating the effects of soil water repellency on the CO2 pulse after wetting; ii) improving understanding of the effects of vegetation fires on post-fire soil CO2 flux; and iii) studying the role of ash produced naturally during vegetation fires in post-fire soil CO2 flux. The results from this research clearly indicate that water repellency is a key controller of the CO2 pulse following the wetting of dry and fire-affected soils. Both the amount of water and the increase in soil water content after wetting are used as indicators of the magnitude of the Birch effect, but this research suggests that their application in water-repellent soils should be re-evaluated. The findings presented here challenge the conceptual notion that the Birch effect is comprised of one large pulse of CO2 and highlights the need to incorporate high-frequency observations during the period following wetting to capture the entire CO2 response to wetting. The results from this thesis suggest that ash is a key player in post-fire C fluxes and should be considered in post-fire C investigations in order to make realistic predictions of the impacts of vegetation fires on C dynamics.</abstract><type>E-Thesis</type><journal/><volume/><journalNumber/><paginationStart/><paginationEnd/><publisher/><placeOfPublication>Swansea</placeOfPublication><isbnPrint/><isbnElectronic/><issnPrint/><issnElectronic/><keywords>soil, carbon, climate change, water repellency, hydrophobicity, wildfire, ash, drying-wetting, Birch effect, CO2 pulse</keywords><publishedDay>12</publishedDay><publishedMonth>3</publishedMonth><publishedYear>2021</publishedYear><publishedDate>2021-03-12</publishedDate><doi>10.23889/SUthesis.57470</doi><url/><notes>A selection of third party content is redacted or is partially redacted from this thesis due to copyright restrictions.ORCiD identifier https://orcid.org/0000-0001-6753-243X</notes><college>COLLEGE NANME</college><CollegeCode>COLLEGE CODE</CollegeCode><institution>Swansea University</institution><supervisor>Urbanek, Emilia ; Doerr, Stefan</supervisor><degreelevel>Doctoral</degreelevel><degreename>Ph.D</degreename><degreesponsorsfunders>Royal Society, Swansea University Doctoral Partnership Training (DTP); Research grant: RG20366, RGF\EA\18062, DH110189</degreesponsorsfunders><apcterm/><lastEdited>2021-07-28T17:27:34.2025179</lastEdited><Created>2021-07-28T16:12:39.7429871</Created><path><level id="1">Faculty of Science and Engineering</level><level id="2">School of Biosciences, Geography and Physics - Geography</level></path><authors><author><firstname>CARMEN</firstname><surname>SANCHEZ-GARCIA</surname><order>1</order></author></authors><documents><document><filename>57470__20482__9b833a5e8c4b4bc197290cb27038e936.pdf</filename><originalFilename>Sanchez-Garcia_Carmen_PhD_Thesis_Final_Redacted.pdf</originalFilename><uploaded>2021-07-28T17:02:09.8138932</uploaded><type>Output</type><contentLength>4638240</contentLength><contentType>application/pdf</contentType><version>Redacted version - open access</version><cronfaStatus>true</cronfaStatus><documentNotes>Copyright: The author, Carmen S&#xE1;nchez-Garc&#xED;a, 2021.</documentNotes><copyrightCorrect>true</copyrightCorrect><language>eng</language></document></documents><OutputDurs/></rfc1807>
spelling 2021-07-28T17:27:34.2025179 v2 57470 2021-07-28 Climate change effects on soil carbon dynamics: CO2 flux from water-repellent and fire-affected soils 748ea0454590c4cd0471f2fbdc496e32 CARMEN SANCHEZ-GARCIA CARMEN SANCHEZ-GARCIA true false 2021-07-28 Climate change is increasing the frequency and intensity of droughts and this is expected to enhance the development of soil water repellency: a very common property of both dry and fire-affected soils. In some regions climate change is also increasing the occurrence and severity of wildfires. Large pulses of CO2 flux from soil to the atmosphere caused by heavy rainfall events (i.e. the Birch effect) can contribute substantially to annual C emissions from soils. However, the effect of the first rainfall after a drought on water-repellent soils and the first post-fire rainfall event on soil CO2 flux remain poorly understood. To address these knowledge gaps this research focuses on: i) investigating the effects of soil water repellency on the CO2 pulse after wetting; ii) improving understanding of the effects of vegetation fires on post-fire soil CO2 flux; and iii) studying the role of ash produced naturally during vegetation fires in post-fire soil CO2 flux. The results from this research clearly indicate that water repellency is a key controller of the CO2 pulse following the wetting of dry and fire-affected soils. Both the amount of water and the increase in soil water content after wetting are used as indicators of the magnitude of the Birch effect, but this research suggests that their application in water-repellent soils should be re-evaluated. The findings presented here challenge the conceptual notion that the Birch effect is comprised of one large pulse of CO2 and highlights the need to incorporate high-frequency observations during the period following wetting to capture the entire CO2 response to wetting. The results from this thesis suggest that ash is a key player in post-fire C fluxes and should be considered in post-fire C investigations in order to make realistic predictions of the impacts of vegetation fires on C dynamics. E-Thesis Swansea soil, carbon, climate change, water repellency, hydrophobicity, wildfire, ash, drying-wetting, Birch effect, CO2 pulse 12 3 2021 2021-03-12 10.23889/SUthesis.57470 A selection of third party content is redacted or is partially redacted from this thesis due to copyright restrictions.ORCiD identifier https://orcid.org/0000-0001-6753-243X COLLEGE NANME COLLEGE CODE Swansea University Urbanek, Emilia ; Doerr, Stefan Doctoral Ph.D Royal Society, Swansea University Doctoral Partnership Training (DTP); Research grant: RG20366, RGF\EA\18062, DH110189 2021-07-28T17:27:34.2025179 2021-07-28T16:12:39.7429871 Faculty of Science and Engineering School of Biosciences, Geography and Physics - Geography CARMEN SANCHEZ-GARCIA 1 57470__20482__9b833a5e8c4b4bc197290cb27038e936.pdf Sanchez-Garcia_Carmen_PhD_Thesis_Final_Redacted.pdf 2021-07-28T17:02:09.8138932 Output 4638240 application/pdf Redacted version - open access true Copyright: The author, Carmen Sánchez-García, 2021. true eng
title Climate change effects on soil carbon dynamics: CO2 flux from water-repellent and fire-affected soils
spellingShingle Climate change effects on soil carbon dynamics: CO2 flux from water-repellent and fire-affected soils
CARMEN SANCHEZ-GARCIA
title_short Climate change effects on soil carbon dynamics: CO2 flux from water-repellent and fire-affected soils
title_full Climate change effects on soil carbon dynamics: CO2 flux from water-repellent and fire-affected soils
title_fullStr Climate change effects on soil carbon dynamics: CO2 flux from water-repellent and fire-affected soils
title_full_unstemmed Climate change effects on soil carbon dynamics: CO2 flux from water-repellent and fire-affected soils
title_sort Climate change effects on soil carbon dynamics: CO2 flux from water-repellent and fire-affected soils
author_id_str_mv 748ea0454590c4cd0471f2fbdc496e32
author_id_fullname_str_mv 748ea0454590c4cd0471f2fbdc496e32_***_CARMEN SANCHEZ-GARCIA
author CARMEN SANCHEZ-GARCIA
author2 CARMEN SANCHEZ-GARCIA
format E-Thesis
publishDate 2021
institution Swansea University
doi_str_mv 10.23889/SUthesis.57470
college_str Faculty of Science and Engineering
hierarchytype
hierarchy_top_id facultyofscienceandengineering
hierarchy_top_title Faculty of Science and Engineering
hierarchy_parent_id facultyofscienceandengineering
hierarchy_parent_title Faculty of Science and Engineering
department_str School of Biosciences, Geography and Physics - Geography{{{_:::_}}}Faculty of Science and Engineering{{{_:::_}}}School of Biosciences, Geography and Physics - Geography
document_store_str 1
active_str 0
description Climate change is increasing the frequency and intensity of droughts and this is expected to enhance the development of soil water repellency: a very common property of both dry and fire-affected soils. In some regions climate change is also increasing the occurrence and severity of wildfires. Large pulses of CO2 flux from soil to the atmosphere caused by heavy rainfall events (i.e. the Birch effect) can contribute substantially to annual C emissions from soils. However, the effect of the first rainfall after a drought on water-repellent soils and the first post-fire rainfall event on soil CO2 flux remain poorly understood. To address these knowledge gaps this research focuses on: i) investigating the effects of soil water repellency on the CO2 pulse after wetting; ii) improving understanding of the effects of vegetation fires on post-fire soil CO2 flux; and iii) studying the role of ash produced naturally during vegetation fires in post-fire soil CO2 flux. The results from this research clearly indicate that water repellency is a key controller of the CO2 pulse following the wetting of dry and fire-affected soils. Both the amount of water and the increase in soil water content after wetting are used as indicators of the magnitude of the Birch effect, but this research suggests that their application in water-repellent soils should be re-evaluated. The findings presented here challenge the conceptual notion that the Birch effect is comprised of one large pulse of CO2 and highlights the need to incorporate high-frequency observations during the period following wetting to capture the entire CO2 response to wetting. The results from this thesis suggest that ash is a key player in post-fire C fluxes and should be considered in post-fire C investigations in order to make realistic predictions of the impacts of vegetation fires on C dynamics.
published_date 2021-03-12T04:13:14Z
_version_ 1763753899540348928
score 10.99342