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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 Black Sand Extended 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 climate exposure may affect plant communities, NWT LTER researchers established 5 experimental sites each containing a pair 10 x 40m rectangular plots. These sites 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 geolocations of individual subplots and sensors within the experiment, measured in summer 2023.
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Root endophyte colonization in the black sand extended growing season experiment for Audubon, Lefty, East Knoll and Trough sites, 2023.
This dataset contains detailed microscopy-based observations of root colonization by three major fungal guilds—arbuscular mycorrhizal fungi (AMF), dark septate endophytes (DSE), and fine root endophytes (FRE)—across multiple alpine plant species sampled from experimental black sand (early snowmelt) plots in the Rocky Mountains. Root samples were collected from plots subjected to different snowmelt timing treatments ("Early" and "Control") using black sand to cause early snowmelt to investigate the effects of phenological shifts in plants on fungal colonization. Each sample includes metadata on collection date, field location, plant species, and staining/scoring logistics, as well as quantified colonization metrics such as hyphae, arbuscules, vesicles, and other fungal structures. This dataset supports ongoing research into how alpine plant–fungal interactions respond to changing environmental conditions and may help identify shifts in mutualistic and non-mutualistic associations under climate-altered snowmelt regimes.
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- Award ID(s):
- 2224439
- PAR ID:
- 10632787
- Publisher / Repository:
- Environmental Data Initiative
- Date Published:
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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