Hierarchical subdivision of Arctic tundra based on vegetation response to climate, parent material and topography

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TitleHierarchical subdivision of Arctic tundra based on vegetation response to climate, parent material and topography
Publication TypeJournal Article
Year of Publication2000
AuthorsWalker, DA
JournalGlobal Change Biology
Volume6
IssueS1
Pagination19-34
Accession NumberARC334
KeywordsArctic, classification, climate, climate change, geology, plant functional types, soils, Tundra, vegetation, vegetation mapping, zonation
Abstract

Current land-cover classifications used for global modelling portray Arctic tundra as one or two classes. This is insufficient for analysis of climate–vegetation interactions. This paper presents a simple three-level vegetation-map legend system useful for modelling at global, regional, and landscape scales. At the highest level (global scale: 107-108 km2) the Tundra Zone is divided into four subzones based on vegetation response to temperature along the latitudinal temperature gradient from north to south: (1) Cushion-forb, (2) Prostrate Dwarf-shrub, (3) Erect Dwarf-shrub, and (4) Low Shrub subzones. The boundaries follow a modification of Yurtsev's phytogeographic subzones. Parent material and topography are also major considerations at global, regional, and landscape scales. Soil pH is a key variable for many ecosystem responses, and a division into acidic (pH 5.5 or less) and nonacidic soils is used. A conceptual mesotopographic gradient is used to characterize the influence of soil-moisture and snow regimes. The example legend framework focuses on the Northern Alaska floristic subprovince, and could be expanded to other floristic provinces using local expert knowledge and available literature. Dominant plant functional types within each habitat type within the four subzones are also presented. Modellers could include or ignore different levels of resolution depending on the purpose of the model. The approach resolves conflicts in terminology that have previously been encountered between the Russian, North American, and Fennoscandian approaches to Arctic zonation.

DOI10.1046/j.1365-2486.2000.06010.x
Short TitleHierarchical subdivision of Arctic tundra based on vegetation response to climate, parent material and topography