Conifer Establishment and Encroachment on Subalpine Meadows around Mt. Baker, WA, USA
The subalpine ecotone is experiencing significant changes in habitat availability and connectivity as a result of climate change. The conversion of meadow habitats to forests has been observed in many mountainous regions. Rates of conifer encroachment into meadows appears to have increased in the 20...
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| Format: | Article |
| Language: | English |
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MDPI AG
2021-10-01
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| Series: | Forests |
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| Online Access: | https://www.mdpi.com/1999-4907/12/10/1390 |
| _version_ | 1797514527384797184 |
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| author | Ben Hagedorn Aquila Flower |
| author_facet | Ben Hagedorn Aquila Flower |
| author_sort | Ben Hagedorn |
| collection | DOAJ |
| description | The subalpine ecotone is experiencing significant changes in habitat availability and connectivity as a result of climate change. The conversion of meadow habitats to forests has been observed in many mountainous regions. Rates of conifer encroachment into meadows appears to have increased in the 20th century, but the patterns of conifer establishment seem highly variable over both space and time. To understand how and why these changes vary temporally and spatially in the Pacific Northwest, we collected cross-sections and whorl counts from conifers along four transects in subalpine meadows around Mt. Baker, Washington. We quantified the relationships between temporal patterns of conifer establishment and a suite of climate variables, and between spatial patterns of conifer density and microsite characteristics. Our results show that establishment occurred in pulses throughout the 20th century, with greater establishment on drier sites during periods of greater precipitation, and greater establishment on wetter sites during periods of higher temperatures. We found that April precipitation and September temperature are particularly strongly correlated with establishment rates, suggesting that the best conditions for conifer seedling establishment occur in years with the warmth and soil moisture needed for the growing season to start earlier or last longer. Within individual meadows, conifer seedling establishment was greater on convex surfaces and in areas with a higher percentage of <i>Vaccinium</i> cover. Our findings at Mt. Baker show that periods of conifer establishment occurred somewhat synchronously across multiple mountains in the region, but we also identified distinct spatial and temporal differences linked to local site conditions. |
| first_indexed | 2024-03-10T06:32:52Z |
| format | Article |
| id | doaj.art-89b1e4aa56794dc9920cffb2fd557575 |
| institution | Directory Open Access Journal |
| issn | 1999-4907 |
| language | English |
| last_indexed | 2024-03-10T06:32:52Z |
| publishDate | 2021-10-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Forests |
| spelling | doaj.art-89b1e4aa56794dc9920cffb2fd5575752023-11-22T18:18:56ZengMDPI AGForests1999-49072021-10-011210139010.3390/f12101390Conifer Establishment and Encroachment on Subalpine Meadows around Mt. Baker, WA, USABen Hagedorn0Aquila Flower1Washington State Department of Natural Resources, Olympia, WA 98501, USAEnvironmental Studies Department, Western Washington University, 516 High St., Bellingham, WA 98225, USAThe subalpine ecotone is experiencing significant changes in habitat availability and connectivity as a result of climate change. The conversion of meadow habitats to forests has been observed in many mountainous regions. Rates of conifer encroachment into meadows appears to have increased in the 20th century, but the patterns of conifer establishment seem highly variable over both space and time. To understand how and why these changes vary temporally and spatially in the Pacific Northwest, we collected cross-sections and whorl counts from conifers along four transects in subalpine meadows around Mt. Baker, Washington. We quantified the relationships between temporal patterns of conifer establishment and a suite of climate variables, and between spatial patterns of conifer density and microsite characteristics. Our results show that establishment occurred in pulses throughout the 20th century, with greater establishment on drier sites during periods of greater precipitation, and greater establishment on wetter sites during periods of higher temperatures. We found that April precipitation and September temperature are particularly strongly correlated with establishment rates, suggesting that the best conditions for conifer seedling establishment occur in years with the warmth and soil moisture needed for the growing season to start earlier or last longer. Within individual meadows, conifer seedling establishment was greater on convex surfaces and in areas with a higher percentage of <i>Vaccinium</i> cover. Our findings at Mt. Baker show that periods of conifer establishment occurred somewhat synchronously across multiple mountains in the region, but we also identified distinct spatial and temporal differences linked to local site conditions.https://www.mdpi.com/1999-4907/12/10/1390subalpine ecotonemount bakerpacific northwestcascade mountainslandscape ecologybiogeography |
| spellingShingle | Ben Hagedorn Aquila Flower Conifer Establishment and Encroachment on Subalpine Meadows around Mt. Baker, WA, USA Forests subalpine ecotone mount baker pacific northwest cascade mountains landscape ecology biogeography |
| title | Conifer Establishment and Encroachment on Subalpine Meadows around Mt. Baker, WA, USA |
| title_full | Conifer Establishment and Encroachment on Subalpine Meadows around Mt. Baker, WA, USA |
| title_fullStr | Conifer Establishment and Encroachment on Subalpine Meadows around Mt. Baker, WA, USA |
| title_full_unstemmed | Conifer Establishment and Encroachment on Subalpine Meadows around Mt. Baker, WA, USA |
| title_short | Conifer Establishment and Encroachment on Subalpine Meadows around Mt. Baker, WA, USA |
| title_sort | conifer establishment and encroachment on subalpine meadows around mt baker wa usa |
| topic | subalpine ecotone mount baker pacific northwest cascade mountains landscape ecology biogeography |
| url | https://www.mdpi.com/1999-4907/12/10/1390 |
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