Ordination of boreal heath-like vegetation with principal component analysis, correspondence analysis and multidimensional scaling
✍ Scribed by Oksanen, J.
- Book ID
- 104621340
- Publisher
- Springer-Verlag
- Year
- 1983
- Tongue
- English
- Weight
- 673 KB
- Volume
- 52
- Category
- Article
- ISSN
- 1573-5052
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✦ Synopsis
Four relatively homogeneous field data sets were analyzed, representing boreal, heath-like forest-floor and rock vegetation in Finland, corresponding to Finnish Calluna and Cladina site types. The methods used were principal c o m p o n e n t analysis (PCA) of covariance matrices, orthogonal correspondence analysis or reciprocal averaging (RA), detrended correspondence analysis (DCA), and linear and nonmetric multidimensional scaling (MDS). R A and D C A gave ordinations in which every species had nearly equal weight. M D S and P C A gave results determined mostly by a few dominant species. M D S and P C A ordinations were very similar to R A and D C A ones when the original data were standardized so that for each species the mean of positive occurrences was the same while quantitative differences within species were retained. RA and P C A were generally very good and reliable, providing that the impact of rare species and outlier relev6s was removed in RA. D C A was slightly less reliable than RA. M D S was sensitive to uneven sampling patterns and was the least reliable method compared.