Climate variability in oxygen and carbon isotopes measured in sagebrush rings from central Nevada

Keywords: sagebrush, tree rings, stable isotopes
Session Type: Virtual Paper
Day: Friday
Session Start / End Time: 4/9/2021 04:40 PM (Pacific Time (US & Canada)) - 4/9/2021 05:55 PM (Pacific Time (US & Canada))
Room: Virtual 30

Abstract

In the Great Basin there is limited information as to how ongoing climate change has been impacting the semi-arid low elevation ecosystems. Big sagebrush (Artemisia tridentata) covers large areas of the arid and semi-arid regions of the western United States, yet to date, only a handful of studies have investigated what sorts of climatic information is contained within the rings of sagebrush. Sagebrush is an incredibly important and ubiquitous species in the western United States, thus studies of how climate variability is recorded by sagebrush could provide the option of developing spacially extensive records as to how climate change is impacting the lower elevations of the Great Basin and the western US. Prior studies of ring-width records from sagebrush have shown correlations with cool-season precipitation and warm-season temperatures, in our study we hoped to use isotopic records to attempt to separate these signals. Here we present a stable isotope chronology (2018-1986) from big sagebrush (Artemisia tridentata) collected from the Monitor Valley in central Nevada. The oxygen isotope chronology developed from the site correlates with cool-season precipitation, whereas the carbon isotope chronology correlates most strongly with summer precipitation and temperature. These chronologies demonstrate the potential for isotopic records of sagebrush, in conjunction with ring widths, to provide information on how sagebrush responds to climate. Finally, although generally short-lived sagebrush chronologies of up to 400 years have been produced in the past (e.g Ferguson, 1964), thus there is also potential to be able to develop climate reconstructions from sagebrush.