Distribution and nitrogen fixation of terricolous lichens in a boreal forest fire chronosequence
Given that nitrogen (N) is a limiting nutrient in boreal ecosystems, biological N fixation can have a large influence on primary production and other processes in this ecosystem. To date, most studies focused on N fixation in boreal ecosystems have focused on bryophyte-cyanobacteria associations, wh...
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| Format: | M2 |
| Language: | Inglés |
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SLU/Dept. of Forest Ecology and Management
2010
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| _version_ | 1855570242976088064 |
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| author | Sandling, Aron |
| author_browse | Sandling, Aron |
| author_facet | Sandling, Aron |
| author_sort | Sandling, Aron |
| collection | Epsilon Archive for Student Projects |
| description | Given that nitrogen (N) is a limiting nutrient in boreal ecosystems, biological N fixation can have a large influence on primary production and other processes in this ecosystem. To date, most studies focused on N fixation in boreal ecosystems have focused on bryophyte-cyanobacteria associations, whereas relatively few studies have investigated the significance of N fixation by lichens. In this study I examined how biomass and aerial N fixation rates of two common terricolous lichens, Nephroma arcticum (L.) Torss. and Peltigera aphthosa (L.) Willd., varied across a boreal chronosequence, where time since fire varied from 43 to 362 years. The main objective of the study was to observe how stand age influenced biomass and N fixation rates of terricolous lichens, which has been extensively described in previous studies for bryophyte-cyanobacteria associations. The study revealed that biomass and consequently N fixation rate per unit area for both lichen species significantly increased with time since fire; whereas, lichen N fixation rates per unit mass was unaffected by stand age. Peltigera aphthosa, but not N. arcticum, demonstrated a significantly higher N fixation rate per unit biomass than the Pleurozium-cyanobacteria association. However, on a per unit area basis, both lichen species demonstrated several orders of magnitude lower N fixation rates relative to the Pleurozium-cyanobacteria association, which was largely driven by differences in biomass per unit area of lichens and bryophytes. This study demonstrates that lichen biomass and N fixation rates per unit area respond positively to the long term absence of wildfire, and further suggest that the contribution of lichens to total forest N fixation rates is minor relative to bryophytes.
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| format | M2 |
| id | RepoSLU910 |
| institution | Swedish University of Agricultural Sciences |
| language | Inglés |
| publishDate | 2010 |
| publishDateSort | 2010 |
| publisher | SLU/Dept. of Forest Ecology and Management |
| publisherStr | SLU/Dept. of Forest Ecology and Management |
| record_format | eprints |
| spelling | RepoSLU9102012-04-20T14:11:28Z Distribution and nitrogen fixation of terricolous lichens in a boreal forest fire chronosequence Sandling, Aron Succession Fire chronosequence Nitrogen fixation Boreal forests Lichens Peltigera aphthosa Nephroma arcticum Given that nitrogen (N) is a limiting nutrient in boreal ecosystems, biological N fixation can have a large influence on primary production and other processes in this ecosystem. To date, most studies focused on N fixation in boreal ecosystems have focused on bryophyte-cyanobacteria associations, whereas relatively few studies have investigated the significance of N fixation by lichens. In this study I examined how biomass and aerial N fixation rates of two common terricolous lichens, Nephroma arcticum (L.) Torss. and Peltigera aphthosa (L.) Willd., varied across a boreal chronosequence, where time since fire varied from 43 to 362 years. The main objective of the study was to observe how stand age influenced biomass and N fixation rates of terricolous lichens, which has been extensively described in previous studies for bryophyte-cyanobacteria associations. The study revealed that biomass and consequently N fixation rate per unit area for both lichen species significantly increased with time since fire; whereas, lichen N fixation rates per unit mass was unaffected by stand age. Peltigera aphthosa, but not N. arcticum, demonstrated a significantly higher N fixation rate per unit biomass than the Pleurozium-cyanobacteria association. However, on a per unit area basis, both lichen species demonstrated several orders of magnitude lower N fixation rates relative to the Pleurozium-cyanobacteria association, which was largely driven by differences in biomass per unit area of lichens and bryophytes. This study demonstrates that lichen biomass and N fixation rates per unit area respond positively to the long term absence of wildfire, and further suggest that the contribution of lichens to total forest N fixation rates is minor relative to bryophytes. SLU/Dept. of Forest Ecology and Management 2010 M2 eng https://stud.epsilon.slu.se/910/ |
| spellingShingle | Succession Fire chronosequence Nitrogen fixation Boreal forests Lichens Peltigera aphthosa Nephroma arcticum Sandling, Aron Distribution and nitrogen fixation of terricolous lichens in a boreal forest fire chronosequence |
| title | Distribution and nitrogen fixation of terricolous lichens in a boreal forest fire chronosequence |
| title_full | Distribution and nitrogen fixation of terricolous lichens in a boreal forest fire chronosequence |
| title_fullStr | Distribution and nitrogen fixation of terricolous lichens in a boreal forest fire chronosequence |
| title_full_unstemmed | Distribution and nitrogen fixation of terricolous lichens in a boreal forest fire chronosequence |
| title_short | Distribution and nitrogen fixation of terricolous lichens in a boreal forest fire chronosequence |
| title_sort | distribution and nitrogen fixation of terricolous lichens in a boreal forest fire chronosequence |
| topic | Succession Fire chronosequence Nitrogen fixation Boreal forests Lichens Peltigera aphthosa Nephroma arcticum |