Table Of ContentSpringer Theses
Recognizing Outstanding Ph.D. Research
Chao You
Geochemical
Behavior
of Levoglucosan
in Tibetan Plateau
Glacier Snow and
Ice
Springer Theses
Recognizing Outstanding Ph.D. Research
Aims and Scope
The series “Springer Theses” brings together a selection of the very best Ph.D.
theses from around the world and across the physical sciences. Nominated and
endorsed by two recognized specialists, each published volume has been selected
foritsscientificexcellenceandthehighimpactofitscontentsforthepertinentfield
of research. For greater accessibility to non-specialists, the published versions
includeanextendedintroduction,aswellasaforewordbythestudent’ssupervisor
explainingthespecialrelevanceoftheworkforthefield.Asawhole,theserieswill
provide a valuable resource both for newcomers to the research fields described,
and for other scientists seeking detailed background information on special
questions. Finally, it provides an accredited documentation of the valuable
contributions made by today’s younger generation of scientists.
Theses are accepted into the series by invited nomination only
and must fulfill all of the following criteria
(cid:129) They must be written in good English.
(cid:129) ThetopicshouldfallwithintheconfinesofChemistry,Physics,EarthSciences,
Engineeringandrelatedinterdisciplinary fields such asMaterials,Nanoscience,
Chemical Engineering, Complex Systems and Biophysics.
(cid:129) The work reported in the thesis must represent a significant scientific advance.
(cid:129) Ifthethesisincludespreviouslypublishedmaterial,permissiontoreproducethis
must be gained from the respective copyright holder.
(cid:129) They must have been examined and passed during the 12 months prior to
nomination.
(cid:129) Each thesis should include a foreword by the supervisor outlining the signifi-
cance of its content.
(cid:129) The theses should have a clearly defined structure including an introduction
accessible to scientists not expert in that particular field.
More information about this series at http://www.springer.com/series/8790
Chao You
Geochemical Behavior
of Levoglucosan in Tibetan
Plateau Glacier Snow and Ice
Doctoral Thesis accepted by the Chinese
Academy of Sciences, Beijing, China
Excellent Doctoral Dissertation of Chinese
Academy of Sciences, 2017
123
Author Supervisor
Dr. ChaoYou Prof. TandongYao
Institute of Tibetan PlateauResearch Institute of Tibetan PlateauResearch
ChineseAcademy of Sciences ChineseAcademy of Sciences
Beijing,China Beijing,China
ChongqingUniversity
Chongqing,China
ISSN 2190-5053 ISSN 2190-5061 (electronic)
SpringerTheses
ISBN978-981-15-7972-1 ISBN978-981-15-7973-8 (eBook)
https://doi.org/10.1007/978-981-15-7973-8
©SpringerNatureSingaporePteLtd.2021
Thisworkissubjecttocopyright.AllrightsarereservedbythePublisher,whetherthewholeorpart
of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations,
recitation, broadcasting, reproduction on microfilms or in any other physical way, and transmission
orinformationstorageandretrieval,electronicadaptation,computersoftware,orbysimilarordissimilar
methodologynowknownorhereafterdeveloped.
The use of general descriptive names, registered names, trademarks, service marks, etc. in this
publicationdoesnotimply,evenintheabsenceofaspecificstatement,thatsuchnamesareexemptfrom
therelevantprotectivelawsandregulationsandthereforefreeforgeneraluse.
The publisher, the authors and the editors are safe to assume that the advice and information in this
book are believed to be true and accurate at the date of publication. Neither the publisher nor the
authors or the editors give a warranty, expressed or implied, with respect to the material contained
hereinorforanyerrorsoromissionsthatmayhavebeenmade.Thepublisherremainsneutralwithregard
tojurisdictionalclaimsinpublishedmapsandinstitutionalaffiliations.
ThisSpringerimprintispublishedbytheregisteredcompanySpringerNatureSingaporePteLtd.
The registered company address is: 152 Beach Road, #21-01/04 Gateway East, Singapore 189721,
Singapore
’
Supervisor s Foreword
As the supervisor of Dr. You Chao’s Ph.D. thesis, I am pleased to introduce the
influential and significant work by Dr. You.
Fire exerts a crucial influence on global ecosystems and human society. This
thesis focuses on geochemical behavior and ancient records of the specific
biomarker, levoglucosan, in Tibetan glacier ice. You’s work first developed a
convincing method for determination of trace concentration of levoglucosan in
glacier ice. Then, You’s work discussed the snow–ice interface processes of
levoglucosan on glacier surfaces, which are necessary in understanding the
environmental significance of levoglucosan records. Finally, You’s work provided
annuallyresolvedlevoglucosanrecordsandfirechangessince1990inaTibetanice
coreanddiscussedtheinteractionamongfire,climatechange,andhumanactivities.
This is the first effort to reconstruct annual resolution fire records in Tibetan ice,
which provides crucial information for improving the knowledge of fire changes
over the subtropical Asia.
I believe that the research results of this thesis can substantially improve the
analytical methods and extend the content of Tibetan ice core records. It will
contribute significantly to the advance of understanding the past fire changes.
Beijing, China Prof. Tandong Yao
September 2020
v
Abstract
Levoglucosanisawidelyusedbiomarkerfortracingfirechangesinenvironmental
studies.Thisthesissummarizedourunderstandingsaboutgeochemicalbehaviorof
levoglucosan in Tibetan Plateau glaciers.
The main findings of this thesis are as follows:
Develop a novel method for determination of levoglucosan at trace concentration
levels in complex matrices of Tibetan glacier samples, by using ultraperformance
liquid chromatography system combined with triple tandem quadrupole mass
spectrometry. The required sample volume is 0.50 mL. The Limit of Detection is
onlyabout0.11 ngmL−1,andwithrecoveryhigherthan90%ataconcentrationof
1 ng mL−1. This method ensures to obtain continuous levoglucosan records in
Tibetan Plateau ice cores to reveal detailed characteristics offire changes.
Evaluatethespatial–temporalvariationsoflevoglucosaninTibetanPlateauglacier
snow and ice. Results supported that Tibetan glaciers mainly acted as receptors of
fire emissions from surrounding regions. Opposite distribution patterns of
levoglucosan were observed on glaciers under different climate backgrounds over
northern and southern parts of the Tibetan Plateau. The highest levoglucosan
concentration was detected near the equilibrium line altitude on glacier surfaces.
Temporal variability in levoglucosan distributions in snow and ice layers may be
affected by chemical leaching on the glacier surface after deposition.
Approvelevoglucosanrecordinicecorethatcanreflectbothlong-termfirechange
trends and strong fire event insights. Levoglucosan record in Tibetan ice core
indicated a rapid increase in fire activities since 1990 over adjacent regions.
Although human activities have substantially modulated fire changes, climate
change acted as a controlling factor for recent increasing fire activities. Increasing
strong wildfires can potentially enhance black carbon deposits on Himalayan gla-
ciers,whichwouldimpactglacialmeltingduringthepre-monsoonwildfireseasons.
Theclimate–firerelationshipsrevealedinthisworkhintathighwildfirerisksunder
the current warming and drying climate situation over the regions adjacent to the
Tibetan Plateau.
vii
viii Abstract
Based on above-mentioned points, we suggested that levoglucosan records in
Tibetanicecorescanbeusedasacreditabletoolforcalibratingandreconstructing
past fire changes.
(cid:1) (cid:1) (cid:1) (cid:1)
Keywords Levoglucosan Fire changes Tibetan Plateau Ice core records
Glacier geochemistry
Main publications for supporting this thesis
1. You C*, Yao T (2019) Fire records in glacier ice. National Science Review
6(3): 384–386. (Reproduced with Permission. Copyright (2019) Oxford
University Press and Science China Press).
2. YouC*,YaoT,XuC(2019)Environmentalsignificanceoflevoglucosanrecords
inacentralTibetanicecore.ScienceBulletin64(2):122–127.(Reproducedwith
Permission.Copyright(2019)ElsevierandScienceChinaPress)
3. You C*, Yao TD, Xu C (2018) Recent increases in wildfires in the Himalayas
andsurrounding regionsdetected incentralTibetanicecore records.Journalof
Geophysical Research: Atmospheres 123(6):3285–3291. (Reproduced with
Permission. Copyright (2018) American Geophysical Union)
4. You C*,Xu C(2018) Reviewoflevoglucosan inglacier snow andice studies:
Recent progress and future perspectives. Science of the Total Environment
616-617:1533–1539.(ReproducedwithPermission.Copyright (2018) Elsevier)
5. You C*, Yao TD, Xu C, et al. (2017) Levoglucosan on Tibetan glaciers under
different atmospheric circulations. Atmospheric Environment 152:1–5.
(Reproduced with Permission. Copyright (2017) Elsevier)
6. You C*, Yao TD, Xu BQ, et al. (2016) Effects of sources, transport, and
postdepositional processes on levoglucosan records in southeastern Tibetan
glaciers. Journal of Geophysical Research: Atmospheres 121(14):8701–8711.
(ReproducedwithPermission.Copyright(2016)AmericanGeophysicalUnion)
7. YouC*,XuC,XuB,etal.(2016)Levoglucosanevidenceforbiomassburning
records over Tibetan glaciers. Environmental Pollution 216:173–181.
(Reproduced with Permission. Copyright (2016) Elsevier)
8. YouC*,SongL,XuB,etal.(2016)Methodfordeterminationoflevoglucosan
in snow and ice at trace concentration levels using ultra-performance liquid
chromatography coupled with triple quadrupole mass spectrometry. Talanta
148:534–538. (Reproduced with Permission. Copyright (2016) Elsevier)
ix
Acknowledgements
ThisthesisisasummaryofworksdonesincemyPh.D.days.Atthisverymoment,
I would like to express my highest respect to my supervisor Prof. Yao Tandong.
Prof. Yao lives up to the Chinese traditional standard of “the teacher, proselytizes
instructs dispels doubt.” I am deeply influenced by his great personality and
scientific insights, which will benefit me for life.
I would also like to express my sincere gratitude toward Prof. Wu Guangjian,
Prof. Xu Baiqing, Prof. Liu Yongqin, and Prof. Tian Lide, for their constructive
suggestionsinsolvingproblemsinmyresearch.Ialsowanttothankmycolleagues
in Prof. Yao’s team: Prof. Yu Wusheng, Prof. Gao Jing, Dr. Zhao Huabiao,
Dr.YangWei,Dr.YangXiaoxin,Dr.GaoYang,Dr.LiShenghai,Dr.ZhuMeilin,
Dr. Dai Yufeng, Dr. Deji, Xia Cuihui, Danzengzhuoga, Wen Xu, and Wang Ping,
I learned a lot from their help.
I also appreciate all the help I get from others during fieldworks.
Finally,I sincerely thank my beloved family. With their support,I have no fear
when I confront with difficulties.
The research in support the thesis was funded by the Second Tibetan Plateau
ScientificExpeditionandResearchProgram(2019QZKK0201),theYouthInnovation
Promotion Association CAS (2020071), the Chinese Academy of Sciences (YIPA-
2020071,andQYZDY-SSW-DQC003),andtheNationalNaturalScienceFoundation
of China (41725001, 41190081 and 41701078).
xi
