Spatial variability of soil hydrophysical properties in Canadian Sphagnum dominated peatlands

Date
2013-01-18
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
Patterned peatlands develop through eco-hydrological feedback loops, resulting in a microtopography of hummocks and hollows. Physical and hydrologic properties were compared between climate zones, peatland types, microform types and depth in relation to elevation and the water table, to determine if the ecologic definition of microforms holds true for their hydrologic properties. Study sites were located near St. Charles-de-Bellechasse, Quebec, and Wandering River, Alberta, and consisted of a bog and fen in each location. Cores were extracted from the field and soil physical properties (bulk density, decomposition, and porosity) and hydrologic properties (saturated and unsaturated hydraulic conductivity, water retention and anisotropy), were measured. Climate may play a potential role in the anisotropy of saturated hydraulic conductivity, while peatland type influences the degree of difference between hummocks and hollows. Saturated hydraulic conductivity is dependent on depth, and supports current model assumptions of higher flow in hollows than in hummocks. Finally, unsaturated hydraulic conductivity is dependent on the physical properties of pore size distribution, inactive to active pore ratio and decomposition status. Implications of the results suggest that model assumptions for saturated K should be based on the presence of macropores or mesopores within the peat matrix, and not bulk density alone. Models that currently use only one hydraulic conductivity value for a peatland apply to only the saturated zone, as microforms significantly impact the unsaturated conditions.
Description
Keywords
Ecology, Hydrology, Physical Geography
Citation
Branham, J. (2013). Spatial variability of soil hydrophysical properties in Canadian Sphagnum dominated peatlands (Master's thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca. doi:10.11575/PRISM/27846