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This dataset was used to answer the question: to what extent do flooding and warming alter plant-community structure in the high-latitude coastal wetlands of the Yukon-Kuskokwim (Y-K) Delta (Western Alaska, USA)? Over two years, we simulated periodic summer tidal flood events at two severity levels and passively increased summer temperatures in a full-factorial field experiment, and measured alterations in aboveground plant functional group (PFG) biomass and composition. We simulated low-severity and high-severity flooding to represent near-future flooding regimes for the Y-K Delta, projected respectively in the next ~5 and ~10 years. The experiment was established in a wet sedge-shrub meadow, an ecotype covering greater than 10% of the vegetated area of the central coast of the Y-K Delta. We characterized aboveground plant-community structure using the point intercept frequency (PIM) methodology. We clumped vascular plant species into five broad PFGs: graminoids, deciduous and evergreen shrubs, forbs, and standing-dead graminoids.
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Wetland plant functional trait responses to experimental warming, flooding, and herbivory, Yukon-Kuskokwim Delta (Western Alaska, USA) (2022-2023)
This dataset was created to understand plant trait responses to warming, flooding, and herbivory in the Yukon-Kuskokwim (Y-K) Delta (western Alaska, USA). We conducted a one-year field mesocosm experiment in which we passively increased temperatures, simulated periodic tidal flooding at two intensity levels (low and high), and applied three components of goose herbivory (grazing, feces addition, and trampling) during the summer growing season. Our treatments reflect changes expected in the Y-K Delta in the next 10-20 years. We conducted the experiment in three community types: a wet sedge-shrub meadow, a tundra, and a transitional wet community between the meadow and tundra, and only sampled the dominant species in these communities. At the end of the season, we harvested height, leaf area, specific leaf area, and leaf dry matter content from randomly selected individuals.
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- Award ID(s):
- 2113641
- PAR ID:
- 10647391
- Publisher / Repository:
- NSF Arctic Data Center
- Date Published:
- Subject(s) / Keyword(s):
- Alaska Arctic vegetation Climate change Ecosystem responses Goose herbivory Inundation Sea-level rise Storm surge flooding Tidal Warming Yukon-Kuskokwim Delta Trampling Feces deposition Leaf economics spectrum
- Format(s):
- Medium: X Other: text/xml
- Sponsoring Org:
- National Science Foundation
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