Newly emerging relationships between form and function reveal the increasingly complex nature of metropolitan regions. The present study investigates spatial diversification in settlement forms and socioeconomic functions in metropolitan Attica (the administrative region including Athens, the capital of Greece), with the aim of implementing a holistic framework assessing urban complexity in contemporary cities.
The amount of variation in species composition among sampling units or beta diversity has become a primary tool for connecting the spatial structure of species assemblages to ecological processes. Many different measures of beta diversity have been developed. Among them, the total variance in the community composition matrix has been proposed as a single-number estimate of beta diversity. In this study, I first show that this measure summarizes the compositional variation among sampling units after nonlinear transformation of species abundances.
An enormous number of measures based on different criteria have been proposed to quantify evenness or unevenness among species relative abundances in an assemblage. However, a unified approach that can encompass most of the widely used indices is still lacking. Here, we first present some basic requirements for an evenness measure.
Measures of phylogenetic diversity have two main objectives: first disentangling the processes that drive species assemblages and second defining priorities of conservation while considering how much each species might contribute to biodiversity. A now widely used approach for measuring phylogenetic diversity consists in summing branch lengths on phylogenetic trees.
© Università degli Studi di Roma "La Sapienza" - Piazzale Aldo Moro 5, 00185 Roma
