Influence of climatic conditions on growth rings of Salix uva-ursi Pursh from the southeastern shore of Hudson Bay, Subarctic Canada

Abstract

Over the past decades, warmer air temperature and spatiotemporal changes in the amount and patterns of precipitation have been observed at high latitudes. Such interannual variability in climatic conditions has a strong influence on the dynamics of biological processes regulating terrestrial ecosystems. Dendroclimatology can improve our understanding of the impacts of climate change on vegetation. Based on ring width and frost rings of bearberry willow (Salix uvaursi) individuals sampled on the southeastern shore of Hudson Bay, Nunavik (Subarctic Québec, Canada), we built a reliable 105-year growth chronology. A complex dendroclimatological analysis, using the standard approach (mean temperature and precipitation sums), extreme variables, and various climatological indices based on daily data, was conducted in order to precisely describe the relationship between annual variations in growth rings and climatic conditions. The growth of Low Arctic willows in the Hudson Bay region is determined by changes in air temperatures as well as precipitation during the summer. However, temperature increases and reductions in amounts of rainfall may intensify drought stress, which is unfavorable for this species. We found that analysis of daily amounts and intensity of precipitation improved our understanding of the factors conditioning the growth of the studied species in an extreme habitat.

Climatic Signals on Growth Ring Variation in Salix herbacea: Comparing Two Contrasting Sites in Iceland

“…The paper outlines the applicability of a new species in dendrochronology and its potential in the analysis of the Arctic environmental change. Salix herbacea has not yet been analyzed to date for its climatic response, while the shrubs of the Willow genus, such as Salix arctica [59][60][61], Salix alaxensis [62], Salix polaris [16,17,20,22,30], and Salix uva-ursi [15], have been widely used as a source of reliable climatic and environmental information for several years. Salix herbacea has visible growth ring boundaries that are measurable and correlated to a relatively high degree with climatic variables, allowing this species to be treated as a reliable source of environmental data.…”

“…Moreover, they represent a major component of groundcover in the Arctic and alpine tundra; therefore, it becomes very important to understand the effects of climate change on dwarf shrubs and their capacity to respond to environmental changes. Tundra plants growing in Arctic environments are very sensitive to climatic conditions and thus specifically useful for dendroclimatic investigations [12][13][14][15][16][17][18][19]. However, researchers have observed, particularly in recent years, an increase in the environmental importance of Arctic dendrochronology research and studies on complex plant responses to changing environmental conditions [14,16,18,[20][21][22][23][24][25].…”

Anatomical characteristics of fossil wood collected from the Manchar Formation (Miocene), Thano Bula Khan, Sindh, Pakistan

“…The colour of the fossil wood was noted to determine the depositional material. Using the ground thin-section method described by Opała-Owczarek et al (2020), nine thin sections were prepared (cross, tangential and radial planes). All the samples were carefully observed under the microscope and all their anatomical features were noted.…”