Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
A PHYSIOLOGICAL APPROACH TO DETERMINING ECOSYSTEM PRODUCTIVITY IN THE ARCTIC: A SENIOR THESIS PRESENTED TO THE FACULTY OF PRINCETON UNIVERSITY IN CANDIDACY FOR THE DEGREE OF BACHELOR OF THE ARTS
Department of Geosciences, Princeton University.
Responsible organisation
2016 (English)Student paper otherStudent thesis
Abstract [en]

In recent decades the Arctic has been warming at a rate of almost twice the global average and this has led to changes in the composition, density, and distribution of arctic vegetation. These changes will have strong influences on the region’s net carbon (C) exchange between land and atmosphere and hold significant implications for future atmospheric [CO2]. However, the precise nature of arctic vegetation change under future warming is not well constrained, highlighting the need for a better understanding of how arctic plants will respond to climate change. In this study, we investigated four key plant mechanisms in Betula pubescens ssp. tortusa: 1) Gross photosynthesis (GOP), 2) Respiration, 3) Rubisco carboxylation (Vc) and oxygenation (Vo), and 4) Mesophyll conductance (gm). Experiments were conducted under varying light intensity and [O2]. For the analysis we utilized a novel method for measuring leaf photosynthesis and respiration that relies on 18O-labelled water, which to the best of our knowledge has never been applied to terrestrial plants, and the measurements collected have not been conducted in this arctic species before. GOP was measured at 10.84 ± 2.11 μmol m-2 s-1 and Vc /Vo was approximately 0.5 for all examined lightintensities. For all [O2] we found that respiration in the light (RLight) was lower than dark respiration (RDark), indicating that respiration is inhibited in the light. The response of gm was shown to increase with increasing light intensity and decrease with decreasing [O2]. Measurements collected agreed with both previous studies and theoretical approximations, which demonstrates that this O2 method is a reliable method of measurement for a wide range of leaf processes. This study is a great development in our understanding of arctic plants, and the unique responses identified in Betula pubescens ssp. tortusa underscore the importance of expanding these measurements to characterize other arctic species.

Place, publisher, year, edition, pages
2016. , 63 p.
National Category
Natural Sciences
Identifiers
URN: urn:nbn:se:polar:diva-3483OAI: oai:DiVA.org:polar-3483DiVA: diva2:1083058
Supervisors
Available from: 2017-03-20 Created: 2017-03-20 Last updated: 2017-03-20Bibliographically approved

Open Access in DiVA

No full text

Other links

http://arks.princeton.edu/ark:/88435/dsp016395w953s
Natural Sciences

Search outside of DiVA

GoogleGoogle Scholar

Total: 3 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf