Climate‐induced yellow‐cedar decline on the island archipelago of Haida Gwaii
Abstract The global rise in temperature and associated changes in climate have led to decline of forests around the globe, across multiple species and ecosystems. Yellow‐cedar (Callitropsis nootkatensis) decline is one of the most severe in North America. We found abundant evidence of tree decline a...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
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Wiley
2021-03-01
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| Series: | Ecosphere |
| Subjects: | |
| Online Access: | https://doi.org/10.1002/ecs2.3427 |
| _version_ | 1818329395505397760 |
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| author | Vanessa M. Comeau Lori D. Daniels Stefan Zeglen |
| author_facet | Vanessa M. Comeau Lori D. Daniels Stefan Zeglen |
| author_sort | Vanessa M. Comeau |
| collection | DOAJ |
| description | Abstract The global rise in temperature and associated changes in climate have led to decline of forests around the globe, across multiple species and ecosystems. Yellow‐cedar (Callitropsis nootkatensis) decline is one of the most severe in North America. We found abundant evidence of tree decline and mortality on Haida Gwaii across multiple watersheds and over a range of elevations. This decline on Haida Gwaii parallels the broader yellow‐cedar decline in terms of spatial distribution, symptoms, magnitude, and timing. However, Haida Gwaii has a more temperate climate and ephemeral snowpack than declining yellow‐cedar forests in Alaska where the link to climate was first uncovered. Given these important differences, we investigated several possible drivers both at the local and at the regional scale, using population demography, dendrochronology, and daily weather data. We explored stand dynamics as a driver and tested the known link to climate. Our results are inconsistent with stand dynamics as a driver of elevated decline and mortality. Neither increased competition nor aging of a cohort explains the decline. Alternatively, the magnitude and timing of the decline are consistent with well‐documented long‐term directional trends in regional climate. Onset of basal area increment decline and mortality have been accumulating over time, with increased rates since the 1980s. Our sites were located at the edge of the expected range of mortality, and we found only four thaw–freeze events over the past ~80 yrs. However, superposed epoch analysis using daily weather data revealed that mortality and onset of decline events were associated with warmer winter conditions, consistent with the drivers from Alaska. Rather than isolated extreme thaw–freeze events, warmer winter temperatures on Haida Gwaii may mean less cold hardening throughout the winter, which exposes yellow‐cedar’s fine roots to varying degrees of freezing damage over multiple winter thaw–freeze cycles, causing physiological stress, tree decline, and eventual death. |
| first_indexed | 2024-12-13T12:47:23Z |
| format | Article |
| id | doaj.art-c573c7602cb94651a46686083fe4192c |
| institution | Directory Open Access Journal |
| issn | 2150-8925 |
| language | English |
| last_indexed | 2024-12-13T12:47:23Z |
| publishDate | 2021-03-01 |
| publisher | Wiley |
| record_format | Article |
| series | Ecosphere |
| spelling | doaj.art-c573c7602cb94651a46686083fe4192c2022-12-21T23:45:27ZengWileyEcosphere2150-89252021-03-01123n/an/a10.1002/ecs2.3427Climate‐induced yellow‐cedar decline on the island archipelago of Haida GwaiiVanessa M. Comeau0Lori D. Daniels1Stefan Zeglen2Department of Forest and Conservation Sciences, Faculty of Forestry The University of British Columbia 2424 Main Mall Vancouver British Columbia CanadaDepartment of Forest and Conservation Sciences, Faculty of Forestry The University of British Columbia 2424 Main Mall Vancouver British Columbia CanadaWest Coast Region British Columbia Ministry of Forests, Lands, Natural Resource Operations and Rural Development 103‐2100 Labieux Road Nanaimo British Columbia CanadaAbstract The global rise in temperature and associated changes in climate have led to decline of forests around the globe, across multiple species and ecosystems. Yellow‐cedar (Callitropsis nootkatensis) decline is one of the most severe in North America. We found abundant evidence of tree decline and mortality on Haida Gwaii across multiple watersheds and over a range of elevations. This decline on Haida Gwaii parallels the broader yellow‐cedar decline in terms of spatial distribution, symptoms, magnitude, and timing. However, Haida Gwaii has a more temperate climate and ephemeral snowpack than declining yellow‐cedar forests in Alaska where the link to climate was first uncovered. Given these important differences, we investigated several possible drivers both at the local and at the regional scale, using population demography, dendrochronology, and daily weather data. We explored stand dynamics as a driver and tested the known link to climate. Our results are inconsistent with stand dynamics as a driver of elevated decline and mortality. Neither increased competition nor aging of a cohort explains the decline. Alternatively, the magnitude and timing of the decline are consistent with well‐documented long‐term directional trends in regional climate. Onset of basal area increment decline and mortality have been accumulating over time, with increased rates since the 1980s. Our sites were located at the edge of the expected range of mortality, and we found only four thaw–freeze events over the past ~80 yrs. However, superposed epoch analysis using daily weather data revealed that mortality and onset of decline events were associated with warmer winter conditions, consistent with the drivers from Alaska. Rather than isolated extreme thaw–freeze events, warmer winter temperatures on Haida Gwaii may mean less cold hardening throughout the winter, which exposes yellow‐cedar’s fine roots to varying degrees of freezing damage over multiple winter thaw–freeze cycles, causing physiological stress, tree decline, and eventual death.https://doi.org/10.1002/ecs2.3427Callitropsis nootkatensisclimate changedendrochronologyforest declineHaida Gwaiitree mortality |
| spellingShingle | Vanessa M. Comeau Lori D. Daniels Stefan Zeglen Climate‐induced yellow‐cedar decline on the island archipelago of Haida Gwaii Ecosphere Callitropsis nootkatensis climate change dendrochronology forest decline Haida Gwaii tree mortality |
| title | Climate‐induced yellow‐cedar decline on the island archipelago of Haida Gwaii |
| title_full | Climate‐induced yellow‐cedar decline on the island archipelago of Haida Gwaii |
| title_fullStr | Climate‐induced yellow‐cedar decline on the island archipelago of Haida Gwaii |
| title_full_unstemmed | Climate‐induced yellow‐cedar decline on the island archipelago of Haida Gwaii |
| title_short | Climate‐induced yellow‐cedar decline on the island archipelago of Haida Gwaii |
| title_sort | climate induced yellow cedar decline on the island archipelago of haida gwaii |
| topic | Callitropsis nootkatensis climate change dendrochronology forest decline Haida Gwaii tree mortality |
| url | https://doi.org/10.1002/ecs2.3427 |
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