CGRG Bibliography of Canadian Geomorphology
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Author : Gignac, L.D.; Nicholson, B.J.; and Bayley, S.E.
Date : 1998.
Title : The utilization of bryophytes in bioclimatic modeling: present distribution of peatlands in the Mackenzie River Basin, Canada.
Publication : The Bryologist
Issue : 101(4):
Page(s) : 560-571.
Abstract
A model was developed that classified and projected the distribution of seven different types of peatlands in the Mackenzie River Basin. The model was based on the relationships between bryophyte indicator species, the types of peatlands they characterize, and regional climate. The model used the presence, absence, and abundance of 15 bryophyte indicator species to classify 81 peatlands in the study area into seven groups. Abundance values were calculated for each of the indicator species along three climatic gradients–Mean Annual Temperature (MAT), Mean Annual Total Precipitation (MATP), and Length of the Growing Season (LGS). The percent cover of all species were then ascribed to appropriate combinations of MAP, MATP, and LGS. The result produced a matrix consisting of 4,560 grid nodes where each node was identified by values for each of the three climatic variables and the types of peatlands that could be found at that climate. An independent data set consisting of climatic and ecological values and vegetation cover for 115 sites was used to test the ability and accuracy of the model to classify and project the climatic distribution of the seven peatland groups. The model correctly classified 106 of the 115 sites and of those, correctly projected the distribution of all but five of the test sites. The model accuracy was 70% for six of the seven groups, and > 90% for three of those. The accuracy for the remaining group was 50% and errors were mostly caused by the failure to project the distribution of three of the test sites. Other errors include: the inability to classify lichen dominated peatlands; the inclusion of wet lawns in bogs into one of the groups which caused a southward extension of that group by approximately 200 km. The overall model accuracy was 88%.
Bibliography of Canadian Geomorphology