The use of lichen growth rings in lichenometry: some preliminary findings
Certain species of crustose lichens have concentrically zoned margins which probably represent yearly growth rings. These marginal growth rings offer an alternative method of studying annual growth fluctuations, establishing growth rate-size curves, and determining the age of thalli for certain crus...
Published in: | Geografiska Annaler: Series A, Physical Geography |
---|---|
Main Authors: | , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
2010
|
Subjects: | |
Online Access: | https://publications.aston.ac.uk/id/eprint/9864/ https://publications.aston.ac.uk/id/eprint/9864/1/The_use_of_lichen_growth_rings_in_lichenometry.pdf |
id |
ftunivaston:oai:publications.aston.ac.uk:9864 |
---|---|
record_format |
openpolar |
spelling |
ftunivaston:oai:publications.aston.ac.uk:9864 2024-05-19T07:42:57+00:00 The use of lichen growth rings in lichenometry: some preliminary findings Armstrong, Richard A. Bradwell, Tom 2010-03 text https://publications.aston.ac.uk/id/eprint/9864/ https://publications.aston.ac.uk/id/eprint/9864/1/The_use_of_lichen_growth_rings_in_lichenometry.pdf en eng https://publications.aston.ac.uk/id/eprint/9864/1/The_use_of_lichen_growth_rings_in_lichenometry.pdf Armstrong, Richard A. <https://publications.aston.ac.uk/view/author/armstrra=40aston=2Eac=2Euk.html> and Bradwell, Tom (2010). The use of lichen growth rings in lichenometry: some preliminary findings. Geografiska Annaler: Series A, 92 (1), pp. 141-147. Article PeerReviewed 2010 ftunivaston 2024-04-23T23:57:33Z Certain species of crustose lichens have concentrically zoned margins which probably represent yearly growth rings. These marginal growth rings offer an alternative method of studying annual growth fluctuations, establishing growth rate-size curves, and determining the age of thalli for certain crustose species. Hence, marginal growth rings represent a potentially valuable, unexploited, tool in lichenometry. In a preliminary study, we measured the widths of the successive marginal rings in 25 thalli of Ochrolechia parella (L.) Massal., growing at a maritime site in north Wales. Mean ring widths of all thalli varied from a minimum of 1.02 mm (the outermost ring) to a maximum of 2.06 mm (the third ring from the margin). There is some suggestion that marginal ring width and thallus size are positively correlated; and hence that growth rates increase in larger thalli in this small population. In a further study on recently exposed bedrock adjacent to Breidalon, SE Iceland, we examined the potential for using marginal growth rings to estimate thallus age of a lichen tentatively identified as a Rhizocarpon (possibly R. concentricum (Davies) Beltram.) and thus confirm the timing of surface exposure (c. 50 years). Collectively, these results suggest: 1) the measurement of marginal rings is a possible alternative method of studying the growth of crustose lichens; 2) O. parella may grow differently to other crustose species, exhibiting a rapidly increasing radial growth rate in thalli >40 mm; 3) where lichens with marginal rings grow on recently exposed surfaces (<60 yrs), minimum age estimates can be made using growth rings as an in situ indication of lichen growth rate; 4) it is suggested that this phenomenon could provide a valuable, previously unexploited, in situ lichenometric-dating tool in areas lacking calibration control. Article in Journal/Newspaper Iceland Aston University: Aston Publications Explorer Geografiska Annaler: Series A, Physical Geography 92 1 141 147 |
institution |
Open Polar |
collection |
Aston University: Aston Publications Explorer |
op_collection_id |
ftunivaston |
language |
English |
description |
Certain species of crustose lichens have concentrically zoned margins which probably represent yearly growth rings. These marginal growth rings offer an alternative method of studying annual growth fluctuations, establishing growth rate-size curves, and determining the age of thalli for certain crustose species. Hence, marginal growth rings represent a potentially valuable, unexploited, tool in lichenometry. In a preliminary study, we measured the widths of the successive marginal rings in 25 thalli of Ochrolechia parella (L.) Massal., growing at a maritime site in north Wales. Mean ring widths of all thalli varied from a minimum of 1.02 mm (the outermost ring) to a maximum of 2.06 mm (the third ring from the margin). There is some suggestion that marginal ring width and thallus size are positively correlated; and hence that growth rates increase in larger thalli in this small population. In a further study on recently exposed bedrock adjacent to Breidalon, SE Iceland, we examined the potential for using marginal growth rings to estimate thallus age of a lichen tentatively identified as a Rhizocarpon (possibly R. concentricum (Davies) Beltram.) and thus confirm the timing of surface exposure (c. 50 years). Collectively, these results suggest: 1) the measurement of marginal rings is a possible alternative method of studying the growth of crustose lichens; 2) O. parella may grow differently to other crustose species, exhibiting a rapidly increasing radial growth rate in thalli >40 mm; 3) where lichens with marginal rings grow on recently exposed surfaces (<60 yrs), minimum age estimates can be made using growth rings as an in situ indication of lichen growth rate; 4) it is suggested that this phenomenon could provide a valuable, previously unexploited, in situ lichenometric-dating tool in areas lacking calibration control. |
format |
Article in Journal/Newspaper |
author |
Armstrong, Richard A. Bradwell, Tom |
spellingShingle |
Armstrong, Richard A. Bradwell, Tom The use of lichen growth rings in lichenometry: some preliminary findings |
author_facet |
Armstrong, Richard A. Bradwell, Tom |
author_sort |
Armstrong, Richard A. |
title |
The use of lichen growth rings in lichenometry: some preliminary findings |
title_short |
The use of lichen growth rings in lichenometry: some preliminary findings |
title_full |
The use of lichen growth rings in lichenometry: some preliminary findings |
title_fullStr |
The use of lichen growth rings in lichenometry: some preliminary findings |
title_full_unstemmed |
The use of lichen growth rings in lichenometry: some preliminary findings |
title_sort |
use of lichen growth rings in lichenometry: some preliminary findings |
publishDate |
2010 |
url |
https://publications.aston.ac.uk/id/eprint/9864/ https://publications.aston.ac.uk/id/eprint/9864/1/The_use_of_lichen_growth_rings_in_lichenometry.pdf |
genre |
Iceland |
genre_facet |
Iceland |
op_relation |
https://publications.aston.ac.uk/id/eprint/9864/1/The_use_of_lichen_growth_rings_in_lichenometry.pdf Armstrong, Richard A. <https://publications.aston.ac.uk/view/author/armstrra=40aston=2Eac=2Euk.html> and Bradwell, Tom (2010). The use of lichen growth rings in lichenometry: some preliminary findings. Geografiska Annaler: Series A, 92 (1), pp. 141-147. |
container_title |
Geografiska Annaler: Series A, Physical Geography |
container_volume |
92 |
container_issue |
1 |
container_start_page |
141 |
op_container_end_page |
147 |
_version_ |
1799482653591732224 |