The Effect of the urban Heat Mosaic on Tree Phenology
Abstract
Due to the heterogeneity of the urban heat island, we can think of the variable influence of urbanization on air temperature as more of an urban heat mosaic. Climate change has caused a resurgence of interest in the way temperature affects how organisms, such as street trees, undergo cyclic changes in their life cycle. Such changes include budburst or, less commonly, timing of senescence. Little is known about how the urban heat mosaic could be affecting the phenology of different urban trees. Because street trees are one of the more prominent ecosystem engineers of the urban landscape, variable influences of temperature on tree phenology could impact urban ecosystem ecology and human health. This study is investigating the timing of senescence for Acer macrophyllum and Acer platanoides in Portland’s hot and cool zones. So far, much has been learned about the methodology surrounding senescence. Data analysis is ongoing, but rates of leaf color change and timing of senescence will be compared for both species in different temperature zones. Further regression analysis will be conducted to determine the relative influences of different factors including moisture availability, diameter at breast height, tree height, soil compaction, and pit width on senescence timing and leaf discoloration. These results will clarify whether there is a significant impact of the urban heat mosaic on phenology of Acer species of trees, which will inform management practices of urban tree planting, and support future research on urban forestry, insect pollination, and use of green space.
Subjects
Plant ecology, Climate Change, Land/watershed management
Persistent Identifier
https://archives.pdx.edu/ds/psu/33834
The Effect of the urban Heat Mosaic on Tree Phenology
Due to the heterogeneity of the urban heat island, we can think of the variable influence of urbanization on air temperature as more of an urban heat mosaic. Climate change has caused a resurgence of interest in the way temperature affects how organisms, such as street trees, undergo cyclic changes in their life cycle. Such changes include budburst or, less commonly, timing of senescence. Little is known about how the urban heat mosaic could be affecting the phenology of different urban trees. Because street trees are one of the more prominent ecosystem engineers of the urban landscape, variable influences of temperature on tree phenology could impact urban ecosystem ecology and human health. This study is investigating the timing of senescence for Acer macrophyllum and Acer platanoides in Portland’s hot and cool zones. So far, much has been learned about the methodology surrounding senescence. Data analysis is ongoing, but rates of leaf color change and timing of senescence will be compared for both species in different temperature zones. Further regression analysis will be conducted to determine the relative influences of different factors including moisture availability, diameter at breast height, tree height, soil compaction, and pit width on senescence timing and leaf discoloration. These results will clarify whether there is a significant impact of the urban heat mosaic on phenology of Acer species of trees, which will inform management practices of urban tree planting, and support future research on urban forestry, insect pollination, and use of green space.
