Morphology-dependent water budgets and nutrient fluxes in arctic thaw ponds

Permafrost and Periglacial Processes
By: , and 

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Abstract

Thaw ponds on the Arctic Coastal Plain of Alaska are productive ecosystems, providing habitat and food resources for many fish and bird species. Permafrost in this region creates unique pond morphologies: deep troughs, shallow low-centred polygons (LCPs) and larger coalescent ponds. By monitoring seasonal trends in pond volume and chemistry, we evaluated whether pond morphology and size affect water temperature and desiccation, and nitrogen (N) and phosphorus (P) fluxes. Evaporation was the largest early-summer water flux in all pond types. LCPs dried quickly and displayed high early-summer nutrient concentrations and losses. Troughs consistently received solute-rich subsurface inflows, which accounted for 12 to 42 per cent of their volume and may explain higher P in the troughs. N to P ratios increased and ammonium concentrations decreased with pond volume, suggesting that P and inorganic N availability may limit ecosystem productivity in older, larger ponds. Arctic summer temperatures will likely increase in the future, which may accelerate mid-summer desiccation. Given their morphology, troughs may remain wet, become warmer and derive greater nutrient loads from their thawing banks. Overall, seasonal- to decadal-scale warming may increase ecosystem productivity in troughs relative to other Arctic Coastal Plain ponds. 

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Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Morphology-dependent water budgets and nutrient fluxes in arctic thaw ponds
Series title Permafrost and Periglacial Processes
DOI 10.1002/ppp.1804
Volume 25
Issue 2
Year Published 2014
Language English
Publisher Wiley
Contributing office(s) Alaska Science Center Water
Description 15 p.
First page 79
Last page 93
Country United States
State Alaska
Online Only (Y/N) N
Additional Online Files (Y/N) N