umu.sePublications
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • 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
Long-term effects of nitrogen deposition on epiphytic lichens
Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
2013 (English)Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
Abstract [en]

The main aim of this study was to analyse the long-term effects on epiphytic lichen dry mass development, diversity and community structure after exposure to a simulated nitrogen deposition gradient. A whole tree experiment was set up in a boreal forest in the County of Västerbotten in Sweden, whereby 15 trees were artificially irrigated and nitrogen fertilized during seven consecutive years (2006-2012). The treatments were equal to an additional deposition of 0.6, 6, 12.5, 25 and 50 kg N ha-1 yr-1. Branches from the trees were collected in October 2012 and the lichen material was harvested and further analysed during the spring 2013. The results from this study showed that the lichens were directly affected by the long-term increased nitrogen deposition. Generally, lichen dry mass and species richness declined at high nitrogen loads and the initial positive effects of low nitrogen loads reported in a preceding study had thus depressed with time. The results from this study also showed that the composition of the lichen community changed benefitting nitrogen-tolerant species, probably not because of competition but more likely because of nitrogen-sensitive species disappearance. This study strongly indicates that it takes more than a few years to detect changes in lichen communities exposed to enhanced nitrogen loads. In addition low concentrations seem to have a cumulative impact. Consequently, this study stresses the importance of also considering the cumulative effect of low nitrogen loads when determining critical values. The critical load for lichen communities in boreal forests might be below 6 kg N ha-1 yr-1.

Place, publisher, year, edition, pages
2013. , 20 p.
Keyword [en]
simulated nitrogen deposition, boreal forest, epiphytic lichens, cumulative loads
National Category
Ecology
Identifiers
URN: urn:nbn:se:umu:diva-72677OAI: oai:DiVA.org:umu-72677DiVA: diva2:626473
Educational program
Master's Programme in Ecology
Supervisors
Examiners
Available from: 2013-09-03 Created: 2013-06-09 Last updated: 2013-10-23Bibliographically approved

Open Access in DiVA

Rönnqvist 2013 Long-term effects of nitrogen deposition on epiphytic lichens(521 kB)456 downloads
File information
File name FULLTEXT01.pdfFile size 521 kBChecksum SHA-512
a4d8ffd4cb4ebab4311d118299c6c83ae9373b9da55e480efc98c2350c3217e6befebc07ed6e681f2baefa962dd0999b6fd11eb40b0690cca5bd9c8bf6a7c1da
Type fulltextMimetype application/pdf

Search in DiVA

By author/editor
Rönnqvist, Marie
By organisation
Department of Ecology and Environmental Sciences
Ecology

Search outside of DiVA

GoogleGoogle Scholar
Total: 456 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

urn-nbn

Altmetric score

urn-nbn
Total: 141 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • 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