Leaf nitrogen and digestibility for Salix pulchra, Betula nana, and Eriophorum vaginatum in short-term (<2 summers) and long-term (~25 summers) warming by open-top chamber in the moist acidic tundra snow fence at Toolik Lake, Alaska, 2018-2019

This is a data set contribution from "Nutritional Landscapes of Arctic Caribou: Observations, Experiments, and Models Provide Process-level Understanding of Forage Traits and Trajectories." These data are part pf a long-term snow fence experiment with areas of deep snow and shallow snow relative to ambient snow depth nearby. Within the distinct snow fence zones, open-top chambers (OTCs) were used to warm the ecosystem between roughly early June and late August. The experiment began in 1994 and has been conducted nearly every summer since then. These OTCs represent the long-term warming effects on moist acidic tundra plants and the ecosystem. In addition, for two summers we established an additional set of OTCs to represent short-term warming effects. Here, we focus sampling on species commonly found in caribou diet (Salix pulchra, Betula nana, and Eriophorum vaginatum) and analyzed leaf tissue for nitrogen (N) concentration, components of dry matter digestibility, and protein precipitation capacity (shrubs only) as a measure of digestibility reducing secondary compounds found in plants.