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Late season thaw depth was measured in the Arctic Long Term Ecological Research (ARC LTER) experimental plots (1981 Moist Acidic Tussock, 1989 Moist Acidic Tussock, 2006 Low Fertilization Moist Acidic Tussock, 1989 Moist Non-acidic Tussock, 1989 Moist Non-acidic Non-tussock and 1989 Wet Sedge tundra) at Toolik Lake, Alaska using a steel thaw probe. Note: for 2017-2018 only 1989 Moist Non-Acidic Tussock Tundra and 2006 Low fertilization Moist Acidic Tussock Tundra were measured. For other sites it has become difficult to distinguish rocks from frozen soil with a steel thaw probe. Starting in 2023 weekly thaw depth measurements were made throughout the growing season in the 2006 Low fertilization Moist Acidic Tussock Tundra experiment.
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Toolik Lake soil biogeochemical data from 35 year long term fertilization experiment, 2015
Dataset from a nutrient addition experiment in moist acidic tundra at the Arctic Long-Term Ecological Research site near Toolik Lake, Alaska. Established in 1981, the field experiment was originally designed to test the response of Arctic tundra vegetation to chronic press disturbances. The split-block design consisted of 5 x 20 meter (m) fertilized and unfertilized plots in four replicate blocks with 1 m buffer strips that were continuously fertilized since 1981 (10 grams (g) Nitrogen (N )and 5 g Phosphorus (P) square meters (m-2) per year (yr-1)). In the 35th year of fertilization (2015) we collected soil samples to quantify the effect of long-term fertilization on soil carbon and nitrogen stocks. We used an isotope labeling laboratory incubation to evaluate how the observed transition from graminoid- to shrub-dominated tundra influenced microbial metabolism and soil carbon dynamics.
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- PAR ID:
- 10689564
- Publisher / Repository:
- NSF Arctic Data Center
- Date Published:
- Subject(s) / Keyword(s):
- soil carbon LTER arctic tundra coupled system feedbacks soil nitrogen carbon isotopes
- Format(s):
- Medium: X Other: text/xml
- Sponsoring Org:
- National Science Foundation
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