A new multivariate approach to studying temporal changes of vegetation

Research output: Contribution to journalArticle

13 Citations (Scopus)

Abstract

We emphasize the necessity of a complex approach to evaluating vegetation change at various levels of abstraction. The analytical steps include comparisons at the data, derived variable, distance, ordination and classification levels. A variety of data randomization methods incorporated in testing the significance of changes in raw data are introduced and compared. It is shown that these are true alternatives to Procrustean comparisons, which offer an apparently unfortunate choice in the presence/absence case. We propose to evaluate nearest neighbor relationships among quadrats in a new method, called adjacency analysis, to detect temporal trends that may remain unrevealed, should our attention be paid to full distance structures only. As an illustration, compositional and structural changes in the rock grassland vegetation of the Sas-hegy Nature Reserve (Budapest, Hungary), intensively sampled by quadrats in 1977 and 2000, are evaluated. Permutation tests show that differences between the 2 years are much smaller than expected by chance alone. Such an overall stability in community structure, however, does not mean that minor aspects of vegetation pattern are invariant over the years. Changes in life form and seed mass spectra are explained by the fluctuation of hemicryptophytes and the slight but detectable expansion of annuals and woody species. Classification is slightly rearranged in time, with clearly detectable within-cluster changes, also depicted in ordination scattergrams.

Original languageEnglish
Pages (from-to)85-100
Number of pages16
JournalPlant Ecology
Volume181
Issue number1
DOIs
Publication statusPublished - Nov 2005

Fingerprint

ordination
vegetation
taxonomy
nature reserve
Hungary
structural change
conservation areas
community structure
grasslands
rocks
grassland
testing
seed
seeds
methodology
rock
method
comparison
test
analysis

Keywords

  • Classification
  • Life forms
  • Manhattan metric
  • Mantel test
  • Matrix rearrangements
  • Nearest neighbors
  • Ordination
  • Procrustes method
  • Seed mass spectra

ASJC Scopus subject areas

  • Forestry
  • Plant Science
  • Ecology

Cite this

A new multivariate approach to studying temporal changes of vegetation. / Podaní, J.; Csontos, P.; Tamás, J.; Miklós, I.

In: Plant Ecology, Vol. 181, No. 1, 11.2005, p. 85-100.

Research output: Contribution to journalArticle

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