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The Turf Transplant Experiment was set up in the summer of 2024. Paired experimental sites were established in two tundra community types - dry meadow and moist meadow - with one site of each community type pair in a lower elevation/warmer area and one site in a higher elevation/cooler area. Subplot turfs (25 cm^2) were transplanted (1) between sites of the same community type at different elevations/temperatures, (2) between plots within the same site or (3) left in place as non-transplant controls. This data package contains trait measurements on Bistort individuals. 

This is a summary of major ion concentrations for stream water samples collected at the outflow of the Saddle stream, near Saddle grid point 007 on Niwot Ridge. 

Pikas are captured, anesthetized, marked with colored ear-tags, non-lethally sampled, and released at point of capture during June-October. Study sites include a gradient of elevation and slope aspect, allowing a comparative study of pika response to variation in climate and sub-surface microclimate. Daily variation in snow cover and sub-surface temperatures are measured using data loggers placed within the territories of marked pikas. Focal territories are revisited at least once to characterize available vegetation via transect sampling and at least annually to service data loggers and record pika survival. Samples collected for genetic and physiological studies include ectoparasites, blood, saliva, urine, feces and hair as well as records of sex, stage, reproductive status, weight, foot length and body temperature. 

As a result of climate change, the Rocky Mountain Front Range is experiencing warmer summers and earlier snowmelt. Due to the importance of snow for regulating soil temperature, growing season length, and available moisture in alpine ecosystems, even small shifts in the snow-free period could have large impacts. The focus of the Growing Season Length Experiment is to examine how terrain-related differences in climate exposure influence the way alpine habitats respond to climate change via earlier snowmelt. To simulate how changes in growing season length may affect biotic and abiotic components, NWT LTER researchers established 5 experimental sites each containing a pair 10 x 40m rectangular plots. These blocks include north and south facing aspects, subalpine and alpine tundra meadows in a range of hydrological conditions (e.g. dry meadows, moist meadows, wet meadows). We accelerated snowmelt in one plot of each block by adding chemically inert black sand, while keeping the second plot as an unmanipulated control (black sand was added to these plots after snow had naturally melted). This dataset includes measurements of soil temperature, moisture, and electrical conductivity. 

This is a summary of major ion concentrations for water samples collected at Green Lake 4. Under summer conditions (June - October) samples were from the outlet stream from the lake; in winter (November - May) they were from the lake, beneath ice cover. 

Starting in 2012 zooplankton sampling at Green Lake 4 was included in the long term monitoring data set at Niwot Ridge. Immediately after the ice has completely melted from the lakes, zooplankton samples are taken once a week for six consecutive weeks at the deepest portion of the lake from an inflatable raft. Zooplankton were sampled at the deepest location of each lake by pulling a conical net (Wisconsin net) vertically through the water column (i.e., vertical tow sample). For each zooplankton sample obtained, adult organisms were identified to species, or lowest taxonomic level (Chydoridae sp. and Bosminidae sp.). Larvae of cladocerans were counted together as neonates; calanoid and cyclopoid copepodites were counted together as nauplii. Individual body lengths of the first 50 -100 (when possible) individuals of each taxon were recorded using a calibrated eyepiece micrometer and means reported. 

This is a summary of major ion concentrations for stream water samples collected at the outflow of the Saddle stream, near Saddle grid point 007 on Niwot Ridge. 

This is a summary of major ion concentrations for stream water samples collected from the stream draining the Arikaree Cirque. Sampling location varied from the channel at the lip of the cirque, where it is first exposed by snowmelt, at the beginning of the season to the outlet from the pond at the foot of the glacier (usually around early July). 

This is a summary of major ion concentrations for stream water samples collected at the Albion site, at the lower end of Green Lakes Valley at the road crossing (culvert) at the Albion camp. 

This is a summary of major ion concentrations for water samples collected at Green Lake 4. Under summer conditions (June - October) samples were from the outlet stream from the lake; in winter (November - May) they were from the lake, beneath ice cover.