Chapter 8
Community Diversity
8.1 Objectives
Today’s concerns about worldwide environmental degradation and the issues of
ecological assessment, monitoring, conservation and restoration, have increased the
interest in measuring the diversity of organisms or other constituents of ecological
communities (cf. Loreau 2010). Its simplest component, species richness, is a single
number that can be easily used outside the scientific community to illustrate ecological issues to the media and decision makers. However, species richness is only a
small element of the story.
In many people’s minds, the words “diversity” or “biodiversity” simply refer to
the number of species in a given area, but actually there are far more dimensions to
the concept of biodiversity. Species diversity itself can be defined and measured in a
variety of ways (cf. Magurran 2004; de Bello et al. 2010; Legendre and Legendre
2012 Sect. 6.5). Other types of diversity exist at various levels of organization of the
living world, ranging from genome to landscape. At the community level, functional
diversity, i.e., the diversity of functional traits, has received much attention in recent
years, as well as phylogenetic diversity. As we did in previous chapters of this book,
we will mostly focus here on species and communities and explore first various
facets of taxonomic diversity.
In this chapter you will:
• get an overview of the concept of diversity in ecology;
• compute various measures of alpha species diversity;
• explore the concept of beta diversity;
• partition beta diversity into its local and species contributions;
• partition beta diversity into replacement, richness difference and nestedness;
• get a brief introduction to the concept of functional diversity
© Springer International Publishing AG, part of Springer Nature 2018
D. Borcard et al., Numerical Ecology with R, Use R!,
https://doi.org/10.1007/978-3-319-71404-2_8
369
Community Diversity
8.1 Objectives
Today’s concerns about worldwide environmental degradation and the issues of
ecological assessment, monitoring, conservation and restoration, have increased the
interest in measuring the diversity of organisms or other constituents of ecological
communities (cf. Loreau 2010). Its simplest component, species richness, is a single
number that can be easily used outside the scientific community to illustrate ecological issues to the media and decision makers. However, species richness is only a
small element of the story.
In many people’s minds, the words “diversity” or “biodiversity” simply refer to
the number of species in a given area, but actually there are far more dimensions to
the concept of biodiversity. Species diversity itself can be defined and measured in a
variety of ways (cf. Magurran 2004; de Bello et al. 2010; Legendre and Legendre
2012 Sect. 6.5). Other types of diversity exist at various levels of organization of the
living world, ranging from genome to landscape. At the community level, functional
diversity, i.e., the diversity of functional traits, has received much attention in recent
years, as well as phylogenetic diversity. As we did in previous chapters of this book,
we will mostly focus here on species and communities and explore first various
facets of taxonomic diversity.
In this chapter you will:
• get an overview of the concept of diversity in ecology;
• compute various measures of alpha species diversity;
• explore the concept of beta diversity;
• partition beta diversity into its local and species contributions;
• partition beta diversity into replacement, richness difference and nestedness;
• get a brief introduction to the concept of functional diversity
© Springer International Publishing AG, part of Springer Nature 2018
D. Borcard et al., Numerical Ecology with R, Use R!,
https://doi.org/10.1007/978-3-319-71404-2_8
369