Weighting, scale dependence and indirect effects in ecological networks

A comparative study

Marco Scotti, J. Podaní, Ferenc Jordán

Research output: Contribution to journalArticle

47 Citations (Scopus)

Abstract

We studied the importance of weighting in ecological interaction networks. Fifty-three weighted interaction networks were analyzed and compared to their unweighted alternatives, based on data taken from two standard databases. We used five network indices, each with weighting and unweighting options, to characterize the positional importance of nodes in these networks. For every network, we ranked the nodes according to their importance values, based on direct and indirect indices and then we compared the rank order of coefficients to reveal potential differences between network types and between indices. We found that (1) weighting affects node ordering very seriously, (2) food webs fundamentally differ from other network types in this respect, (3) direct and indirect indices provide fairly different results but indirect effects are similar if longer than two steps, and (4) the effect of weighting depends on the number of network nodes in case of direct interactions only. We concluded that the importance of interaction weights may depend on the evolutionary stability of interaction types.

Original languageEnglish
Pages (from-to)148-159
Number of pages12
JournalEcological Complexity
Volume4
Issue number3
DOIs
Publication statusPublished - Sep 2007

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Keywords

  • Centrality
  • Ecological network
  • Indirect effects
  • Interaction strength
  • Positional importance
  • Scale independence

ASJC Scopus subject areas

  • Ecology
  • Environmental Science(all)

Cite this

Weighting, scale dependence and indirect effects in ecological networks : A comparative study. / Scotti, Marco; Podaní, J.; Jordán, Ferenc.

In: Ecological Complexity, Vol. 4, No. 3, 09.2007, p. 148-159.

Research output: Contribution to journalArticle

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