Identifying multiscale zonation and assessing the relative importance of polygon geomorphology on carbon fluxes in an Arctic tundra ecosystem

TitleIdentifying multiscale zonation and assessing the relative importance of polygon geomorphology on carbon fluxes in an Arctic tundra ecosystem
Publication TypeJournal Article
Year of Publication2015
AuthorsWainwright, Haruko M., Dafflon Baptiste, Smith Lydia J., Hahn Melanie S., Curtis John B., Wu Yuxin, Ulrich Craig, Peterson John E., Torn Margaret S., and Hubbard Susan S.
JournalJournal of Geophysical Research: Biogeosciences
Volume120
Issue4
Pagination788 - 808
Date PublishedJan-04-2015
Abstract

We develop a multiscale zonation approach to characterize the spatial variability of Arctic polygonal ground geomorphology and to assess the relative controls of these elements on land surface and subsurface properties and carbon fluxes. Working within an ice wedge polygonal region near Barrow, Alaska, we consider two scales of zonation: polygon features (troughs, centers, and rims of polygons) that are nested within different polygon types (high, flat, and low centered). In this study, we first delineated polygons using a digital elevation map and clustered the polygons into four types along two transects, using geophysical and kite-based landscape-imaging data sets. We extrapolated those data-defined polygon types to all the polygons over the study site, using the polygon statistics extracted from the digital elevation map. Based on the point measurements, we characterized the distribution of vegetation, hydrological, thermal, and geochemical properties, as well as carbon fluxes, all as a function of polygon types and polygon features. Results show that nested polygon geomorphic zonation—polygon types and polygon features—can be used to represent distinct distributions of carbon fluxes and associated properties, as well as covariability among those properties. Importantly, the results indicate that polygon types have more power to explain the variations in those properties than polygon features. The approach is expected to be useful for improved system understanding, site characterization, and parameterization of numerical models aimed at predicting ecosystem feedbacks to the climate.

URLhttp://doi.wiley.com/10.1002/2014JG002799
DOI10.1002/2014JG002799
Short TitleJ. Geophys. Res. Biogeosci.