Will aspen (Populus tremula) disappear from protected old-growth forest areas: long-term patterns of aspen dynamics
Conservation of forest biodiversity often relies on protected areas. However, protected areas cover only a marginal proportion of land. Furthermore, their characteristics may change, for example, due to natural succession. European aspen (Populus tremula) is a keystone species for boreal forest biod...
Published in: | Proceedings of the 5th European Congress of Conservation Biology |
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Main Authors: | , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Open Science Centre, University of Jyväskylä
2018
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Subjects: | |
Online Access: | https://doi.org/10.17011/conference/eccb2018/107270 http://urn.fi/ |
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ftjyvaeskylaenun:oai:jyx.jyu.fi:123456789/61806 |
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Open Polar |
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JYX - Jyväskylä University Digital Archive |
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English |
description |
Conservation of forest biodiversity often relies on protected areas. However, protected areas cover only a marginal proportion of land. Furthermore, their characteristics may change, for example, due to natural succession. European aspen (Populus tremula) is a keystone species for boreal forest biodiversity but there is an obvious risk of disappearance of aspen from nature reserves as a result of stand succession. More specifically, the long-term dynamics of aspen populations in conservation areas is not known empirically. For example, it is unclear if there is recruitment to balance the mature tree mortality and maintain long-term persistence of aspen in these areas. In order to evaluate aspen dynamics in protected forests, we conducted areawide, full-coverage surveys in 15 nature reserves in North Karelia, Finland to see if a lack of recruitment is seen in the long-term age-distribution of aspen. These surveys were conducted twice over a span of 18 years, one being in 1999(1) and the other in 2017. We found declines of on average 75 % for dead aspens and 41 % for living aspens per area, with similar declines per ha, and in volume per area and per ha between 1999 and 2017. Human-caused notching had increased the amount of dead wood in 1999 way beyond a natural level, which was also reflected in the deadwood to living wood ratio. The recent estimate from 2017 probably reflects naturally occurring mortality patterns of aspen as the deadwood to living wood ratio declined. Tentative analyses also indicate distribution shifts in diameter at breast height and decay classes (separated in fallen, standing whole trees and standing broken trees) during this 18 year period. Moreover, it appears that there is a continuous lack of recruitment despite a high amount of regeneration in each area. The current recruitment occurs primarily on open areas and edges, often adjacent to managed forests or roads bordering the conservation areas. Our study showcases the highly dynamic nature of forest conservation areas, due to naturally occurring stand succession, and its possible consequences for biodiversity. Aspen maintains a diverse group of other species. If aspen vanishes from conservation areas like the ones studied, it may lead to the extinction of several other species. It seems evident that conservation of aspen-associated species is impossible only with the current network of conservation areas. The solution is likely to be found in managing the surrounding commercial forests for these species, although further research into this issue is required. 1. Kouki, J., Arnold, K., & Martikainen, P. (2004). Long-term persistence of aspen - a key host for many threatened species - is endangered in old-growth conservation areas in Finland. Journal for Nature Conservation, 12(1), 41-52. doi:10.1016/j.jnc.2003.08.002 peerReviewed |
format |
Article in Journal/Newspaper |
author |
Hardenbol, Alwin Junninen, Kaisa Kouki, Jari |
spellingShingle |
Hardenbol, Alwin Junninen, Kaisa Kouki, Jari Will aspen (Populus tremula) disappear from protected old-growth forest areas: long-term patterns of aspen dynamics |
author_facet |
Hardenbol, Alwin Junninen, Kaisa Kouki, Jari |
author_sort |
Hardenbol, Alwin |
title |
Will aspen (Populus tremula) disappear from protected old-growth forest areas: long-term patterns of aspen dynamics |
title_short |
Will aspen (Populus tremula) disappear from protected old-growth forest areas: long-term patterns of aspen dynamics |
title_full |
Will aspen (Populus tremula) disappear from protected old-growth forest areas: long-term patterns of aspen dynamics |
title_fullStr |
Will aspen (Populus tremula) disappear from protected old-growth forest areas: long-term patterns of aspen dynamics |
title_full_unstemmed |
Will aspen (Populus tremula) disappear from protected old-growth forest areas: long-term patterns of aspen dynamics |
title_sort |
will aspen (populus tremula) disappear from protected old-growth forest areas: long-term patterns of aspen dynamics |
publisher |
Open Science Centre, University of Jyväskylä |
publishDate |
2018 |
url |
https://doi.org/10.17011/conference/eccb2018/107270 http://urn.fi/ |
long_lat |
ENVELOPE(-117.453,-117.453,56.733,56.733) |
geographic |
Deadwood |
geographic_facet |
Deadwood |
genre |
karelia* |
genre_facet |
karelia* |
op_relation |
https://peerageofscience.org/conference/eccb2018/107270/ ECCB2018: 5th European Congress of Conservation Biology. 12th - 15th of June 2018, Jyväskylä, Finland Hardenbol, A., Junninen, K. and Kouki, J. (2018). Will aspen (Populus tremula) disappear from protected old-growth forest areas: long-term patterns of aspen dynamics. 5th European Congress of Conservation Biology. doi:10.17011/conference/eccb2018/107270 doi:10.17011/conference/eccb2018/107270 http://urn.fi/ |
op_rights |
CC BY 4.0 © the Authors, 2018 openAccess http://creativecommons.org/licenses/by/4.0/ |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.17011/conference/eccb2018/107270 |
container_title |
Proceedings of the 5th European Congress of Conservation Biology |
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1766052955674378240 |
spelling |
ftjyvaeskylaenun:oai:jyx.jyu.fi:123456789/61806 2023-05-15T17:00:18+02:00 Will aspen (Populus tremula) disappear from protected old-growth forest areas: long-term patterns of aspen dynamics Hardenbol, Alwin Junninen, Kaisa Kouki, Jari 2018 text/html fulltext https://doi.org/10.17011/conference/eccb2018/107270 http://urn.fi/ eng eng Open Science Centre, University of Jyväskylä https://peerageofscience.org/conference/eccb2018/107270/ ECCB2018: 5th European Congress of Conservation Biology. 12th - 15th of June 2018, Jyväskylä, Finland Hardenbol, A., Junninen, K. and Kouki, J. (2018). Will aspen (Populus tremula) disappear from protected old-growth forest areas: long-term patterns of aspen dynamics. 5th European Congress of Conservation Biology. doi:10.17011/conference/eccb2018/107270 doi:10.17011/conference/eccb2018/107270 http://urn.fi/ CC BY 4.0 © the Authors, 2018 openAccess http://creativecommons.org/licenses/by/4.0/ CC-BY Article http://purl.org/eprint/type/ConferenceItem conference paper not in proceedings publishedVersion conferenceObject 2018 ftjyvaeskylaenun https://doi.org/10.17011/conference/eccb2018/107270 2021-09-23T20:21:52Z Conservation of forest biodiversity often relies on protected areas. However, protected areas cover only a marginal proportion of land. Furthermore, their characteristics may change, for example, due to natural succession. European aspen (Populus tremula) is a keystone species for boreal forest biodiversity but there is an obvious risk of disappearance of aspen from nature reserves as a result of stand succession. More specifically, the long-term dynamics of aspen populations in conservation areas is not known empirically. For example, it is unclear if there is recruitment to balance the mature tree mortality and maintain long-term persistence of aspen in these areas. In order to evaluate aspen dynamics in protected forests, we conducted areawide, full-coverage surveys in 15 nature reserves in North Karelia, Finland to see if a lack of recruitment is seen in the long-term age-distribution of aspen. These surveys were conducted twice over a span of 18 years, one being in 1999(1) and the other in 2017. We found declines of on average 75 % for dead aspens and 41 % for living aspens per area, with similar declines per ha, and in volume per area and per ha between 1999 and 2017. Human-caused notching had increased the amount of dead wood in 1999 way beyond a natural level, which was also reflected in the deadwood to living wood ratio. The recent estimate from 2017 probably reflects naturally occurring mortality patterns of aspen as the deadwood to living wood ratio declined. Tentative analyses also indicate distribution shifts in diameter at breast height and decay classes (separated in fallen, standing whole trees and standing broken trees) during this 18 year period. Moreover, it appears that there is a continuous lack of recruitment despite a high amount of regeneration in each area. The current recruitment occurs primarily on open areas and edges, often adjacent to managed forests or roads bordering the conservation areas. Our study showcases the highly dynamic nature of forest conservation areas, due to naturally occurring stand succession, and its possible consequences for biodiversity. Aspen maintains a diverse group of other species. If aspen vanishes from conservation areas like the ones studied, it may lead to the extinction of several other species. It seems evident that conservation of aspen-associated species is impossible only with the current network of conservation areas. The solution is likely to be found in managing the surrounding commercial forests for these species, although further research into this issue is required. 1. Kouki, J., Arnold, K., & Martikainen, P. (2004). Long-term persistence of aspen - a key host for many threatened species - is endangered in old-growth conservation areas in Finland. Journal for Nature Conservation, 12(1), 41-52. doi:10.1016/j.jnc.2003.08.002 peerReviewed Article in Journal/Newspaper karelia* JYX - Jyväskylä University Digital Archive Deadwood ENVELOPE(-117.453,-117.453,56.733,56.733) Proceedings of the 5th European Congress of Conservation Biology |