Roles of neighboring plants and temperature on growth and survival of white spruce seedlings along elevational gradients in Alaska
Thesis (M.S.) University of Alaska Fairbanks, 2018 Seedlings are the most vulnerable stage of a tree's life and their successful survival and growth are critical to support future forests. Recent rapid warming in Alaska has promoted the movement of treeline upward in elevation, while trees at l...
Main Author: | |
---|---|
Other Authors: | , , |
Format: | Thesis |
Language: | English |
Published: |
2018
|
Subjects: | |
Online Access: | http://hdl.handle.net/11122/8735 |
id |
ftunivalaska:oai:scholarworks.alaska.edu:11122/8735 |
---|---|
record_format |
openpolar |
spelling |
ftunivalaska:oai:scholarworks.alaska.edu:11122/8735 2023-05-15T18:40:46+02:00 Roles of neighboring plants and temperature on growth and survival of white spruce seedlings along elevational gradients in Alaska Okano, Kyoko Bret-Harte, M. Syndonia Mulder, Christa P. H. Juday, Glenn P. 2018-05 http://hdl.handle.net/11122/8735 en_US eng http://hdl.handle.net/11122/8735 Department of Biology and Wildlife White spruce Seedlings Ecophysiology Alaska Denali National Park and Preserve Growth Mortality Losses Climatic factors Effect of altitude on Effect of cold on Effect of global warming on Effect of light on Thesis ms 2018 ftunivalaska 2023-02-23T21:37:06Z Thesis (M.S.) University of Alaska Fairbanks, 2018 Seedlings are the most vulnerable stage of a tree's life and their successful survival and growth are critical to support future forests. Recent rapid warming in Alaska has promoted the movement of treeline upward in elevation, while trees at low elevations have decreased their growth. Understanding the direct effects of warming and the indirect effects induced by warming, such as species interactions, on the dominant treeline species, white spruce (Picea glauca) is key to sustaining boreal forests, from low elevations to above current treeline. The objectives of my thesis were to assess the roles that warming, neighboring interaction, habitat type, elevation and season play in the survival and growth of white spruce in Denali National Park and Preserve and Fairbanks, Alaska, USA. I planted spruce seedlings where I manipulated summer temperature and neighbor plants at seven sites (forest or tundra) along an elevational gradient that crossed treeline. I measured survival after winter and summer seasons, and harvested the seedlings for biomass after the third growing season. I found that competition -- particularly light competition where seedlings were shaded -- was the most important factor for seedling growth, while along elevational gradients, temperature and season had inverse effects on their survival: more seedlings at high elevations survived in summer and under warming, but more seedlings at low elevations survived in winter and under ambient temperatures. More seedlings with neighbors survived in summer and in forests, suggesting facilitation through shading. I found some evidence for a trade-off between growth and survival. Seedlings with a high relative growth in height (RGR height) in 2012 had a lower survival rate than seedlings with a low RGR height in the following hot and dry summer of 2013. More seedlings planted with neighbors that had a small diameter in 2012 also survived in 2013, but not without neighbors. These results suggest that a ... Thesis Tundra Alaska University of Alaska: ScholarWorks@UA Fairbanks |
institution |
Open Polar |
collection |
University of Alaska: ScholarWorks@UA |
op_collection_id |
ftunivalaska |
language |
English |
topic |
White spruce Seedlings Ecophysiology Alaska Denali National Park and Preserve Growth Mortality Losses Climatic factors Effect of altitude on Effect of cold on Effect of global warming on Effect of light on |
spellingShingle |
White spruce Seedlings Ecophysiology Alaska Denali National Park and Preserve Growth Mortality Losses Climatic factors Effect of altitude on Effect of cold on Effect of global warming on Effect of light on Okano, Kyoko Roles of neighboring plants and temperature on growth and survival of white spruce seedlings along elevational gradients in Alaska |
topic_facet |
White spruce Seedlings Ecophysiology Alaska Denali National Park and Preserve Growth Mortality Losses Climatic factors Effect of altitude on Effect of cold on Effect of global warming on Effect of light on |
description |
Thesis (M.S.) University of Alaska Fairbanks, 2018 Seedlings are the most vulnerable stage of a tree's life and their successful survival and growth are critical to support future forests. Recent rapid warming in Alaska has promoted the movement of treeline upward in elevation, while trees at low elevations have decreased their growth. Understanding the direct effects of warming and the indirect effects induced by warming, such as species interactions, on the dominant treeline species, white spruce (Picea glauca) is key to sustaining boreal forests, from low elevations to above current treeline. The objectives of my thesis were to assess the roles that warming, neighboring interaction, habitat type, elevation and season play in the survival and growth of white spruce in Denali National Park and Preserve and Fairbanks, Alaska, USA. I planted spruce seedlings where I manipulated summer temperature and neighbor plants at seven sites (forest or tundra) along an elevational gradient that crossed treeline. I measured survival after winter and summer seasons, and harvested the seedlings for biomass after the third growing season. I found that competition -- particularly light competition where seedlings were shaded -- was the most important factor for seedling growth, while along elevational gradients, temperature and season had inverse effects on their survival: more seedlings at high elevations survived in summer and under warming, but more seedlings at low elevations survived in winter and under ambient temperatures. More seedlings with neighbors survived in summer and in forests, suggesting facilitation through shading. I found some evidence for a trade-off between growth and survival. Seedlings with a high relative growth in height (RGR height) in 2012 had a lower survival rate than seedlings with a low RGR height in the following hot and dry summer of 2013. More seedlings planted with neighbors that had a small diameter in 2012 also survived in 2013, but not without neighbors. These results suggest that a ... |
author2 |
Bret-Harte, M. Syndonia Mulder, Christa P. H. Juday, Glenn P. |
format |
Thesis |
author |
Okano, Kyoko |
author_facet |
Okano, Kyoko |
author_sort |
Okano, Kyoko |
title |
Roles of neighboring plants and temperature on growth and survival of white spruce seedlings along elevational gradients in Alaska |
title_short |
Roles of neighboring plants and temperature on growth and survival of white spruce seedlings along elevational gradients in Alaska |
title_full |
Roles of neighboring plants and temperature on growth and survival of white spruce seedlings along elevational gradients in Alaska |
title_fullStr |
Roles of neighboring plants and temperature on growth and survival of white spruce seedlings along elevational gradients in Alaska |
title_full_unstemmed |
Roles of neighboring plants and temperature on growth and survival of white spruce seedlings along elevational gradients in Alaska |
title_sort |
roles of neighboring plants and temperature on growth and survival of white spruce seedlings along elevational gradients in alaska |
publishDate |
2018 |
url |
http://hdl.handle.net/11122/8735 |
geographic |
Fairbanks |
geographic_facet |
Fairbanks |
genre |
Tundra Alaska |
genre_facet |
Tundra Alaska |
op_relation |
http://hdl.handle.net/11122/8735 Department of Biology and Wildlife |
_version_ |
1766230183994458112 |