ISSN:
1573-5052
Keywords:
Binary Discriminant Analysis
;
Disturbances
;
Ecological groups
;
Morphogenic features
;
Phytogeomorphology
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
Notes:
Abstract An ecological study of the Municipalité Régionale de Comté (MRC) du Haut-Saint-Laurent area, a highly disturbed landscape located south-west of Montréal (Québec), was carried out. The aim of this study was to establish links between indicator species of ecosystems and geomorphological features in a heavily disturbed background. Analysis to obtain the ecological groups are based on the links of herbaceous plants and shrubs. This approach is defined as a sociological one where grouping is based only on the species' affinity. In order to obtain ecological groups, similarity measures using the chi-square coefficient were calculated on the relative cover values of the 150 retained species from 452 plots. An intermediate linkage cluster analysis was then performed on the similarity matrix thus created. By this procedure, 56 ecological groups were obtained. These groups were then characterized according to abiotic variables, especially the geomorphological data, by the use of binary discriminant analysis. Results indicate that 39 of these 56 groups were significantly associated specifically with one of 10 morphogenic features, while 13 of these 56 groups were associated with 2 or 3 features. The ecological groups which were associated with one specific geomorphological process showed a strong link to one texture and one specific drainage class. On the other hand, the groups which were associated with several features were linked with one drainage class, usually imperfect, and a certain topographic situation. However, ecological groups showing a strong association to more than one feature can be of cartographic use, provided soil texture is analysed to determine the origin of the deposit. Finally, the type of deposit becomes non determinant on vegetation where drainage and topographic variables indicate poorly or very poorly drained sites. Non-significant groups should be used as indicators of drainage and topographical conditions but not as indicators of geomorphological deposits. The ecological groups not associated with morphogenic features demonstrated mostly a heliophilic character. Thus, the ubiquitous character of ecological groups is not exclusive to species taking advantage of disturbances.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00031701
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