Journal ArticleDOI
An Examination of Some Ordination Problems By Use of Simulated Vegetational Data
TLDR
In this article, a single ordination procedure was evaluated by its ability to detect the ecological information in the hypothetical models and the procedure was reasonably successful when the data were drawn from a short length of the gradient but became progressively less so as longer lengths of the environmental gradient were included in the data.Abstract:
Hypothetical vegetation models were made to simulate numerical changes in species populations along a single environmental gradient. A single ordination procedure was evaluated by its ability to detect the ecological information in the hypothetical models. The procedure was reasonably successful when the data were drawn from a short length of the gradient but became progressively less so as longer lengths of the environmental gradient were included in the data. This parallels an increase in the number of stands from which each species is absent in the total data set. Zero values appear to mask ecological information, and an intuitive method of assigning "degree of absence" values to the data is described. After this adjustment, ordination patterns were easier to interpret because ecological information was concentrated in fewer axes. See full-text article at JSTORread more
Citations
More filters
Book ChapterDOI
Detrended correspondence analysis: an improved ordination technique
M. O. Hill,Hugh G. Gauch +1 more
TL;DR: DCA consistently gives the most interpretable ordination results, but as always the interpretation of results remains a matter of ecological insight and is improved by field experience and by integration of supplementary environmental data for the vegetation sample sites.
Book ChapterDOI
Compositional dissimilarity as a robust measure of ecological distance
TL;DR: In this article, the authors evaluated the robustness of quantitative measures of compositional dissimilarity between sites using extensive computer simulations of species' abundance patterns over one and two dimensional configurations of sample sites in ecological space.
Book ChapterDOI
An evaluation of the relative robustness of techniques for ecological ordination
TL;DR: In this article, simulated vegetation data were used to assess the relative robustness of ordination techniques to variations in the model of community variation in relation to environment, and the results clearly demonstrated the ineffectiveness of linear techniques (PCA, PCoA), due to curvilinear distortion.
Book ChapterDOI
Bray-curtis ordination: an effective strategy for analysis of multivariate ecological data
TL;DR: This article proposed principal component analysis (PCA), reciprocal averaging, and iterative stress minimization (ISM) techniques to deal with the distortion of the original multivariate data set.
Journal ArticleDOI
Applying Metric and Nonmetric Multidimensional Scaling to Ecological Studies: Some New Results
N. C. Kenkel,László Orlóci +1 more
TL;DR: In this paper, the authors compared metric and non-metric multidimensional scaling strategies for ecological ordination, based on simulated coenoplane data showing varying degrees of species turnover on two independent environmental axes.
References
More filters
Journal ArticleDOI
An Ordination of the Upland Forest Communities of Southern Wisconsin
Roger H. Bray,John T. Curtis +1 more
TL;DR: It is shown that nature of unit variation is a naajor problenl in systematies, and that whether this variation is diserete, continuous, or in some other form, there is a need for appliGation of (uantitative and statistical methods.
Book
Principles of numerical taxonomy
Robert R. Sokal,P.H.A. Sneath +1 more
TL;DR: The authors continued the story of psychology with added research and enhanced content from the most dynamic areas of the field, such as cognition, gender and diversity studies, neuroscience and more, while at the same time using the most effective teaching approaches and learning tools.
Journal ArticleDOI
Gradient analysis of vegetation
TL;DR: In this article, the authors propose a method to solve the problem of the problem: this article...,.. ].. ).. ]... )...