EVOME field crews have been diligently working to collect, sample, and process environmental data while researchers in the lab have been finalizing samples and synthesizing findings from last year’s field season. A small group of five researchers have spent the past two weeks studying the vegetation at each site, stream discharge, took soil cores, placed soil cation and anion resin strips, and checked permafrost thaw depth. Soil samples were each placed in a potassium chloride solution to extract nutrients then filtered down to analyze inorganic nitrogen composition stored in the soil.
Additionally, while studying the growth patterns of two willow species, a Ph.D. student, undergraduate research assistant, and REU student have found that Vc,max25 is not solely determinant of willow growth rates. The Ph.D. student, Ian Shuman, hypothesizes that both genetic markers and environmental factors are intertwined in how physiology impacts growth. To do this, the researchers will focus on quantifying differences in growth across sites. They will do this by using a LI-COR LI-6800 to measure the rate of photosynthesis in the willow leaves, including continuous measurement of carbon dioxide levels. As a way to track environmental variation across sites, this team has been measuring permafrost thaw depth, soil moisture, and willow morphology. The group has been measuring diameter and length of willow branches to determine their growth rates going as far back as 2011 to see temporal patterns.
Technician Jon Ibarguren separates red blood cells from plasma in collected Gambel’s White-Crowned Sparrow blood samples to prepare them for isotope dietary analysis. Photo: Maura Barry.
REU Milana Krishnevsky takes water samples and collects leaf litter bags from central site streams. The leaf litter will be analyzed to determine the role of willow decomposition on stream food webs. Water samples will be used to determine the stream’s chemistry. Photo: Dana Drake.
