biodiversity

Quantifying evenness and linking it to diversity, beta diversity, and similarity

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.

Time-lapsing biodiversity. An open source method for measuring diversity changes by remote sensing

Understanding biodiversity changes in time is crucial to promptly provide management practices against diversity loss. This is overall true when considering global scales, since human-induced global change is expected to make significant changes on the Earth's biota. Biodiversity management and planning is mainly based on field observations related to community diversity, considering different taxa. However, such methods are time and cost demanding and do not allow in most cases to get temporal replicates.

Estimating tree species diversity from space in an alpine conifer forest. The Rao's Q diversity index meets the spectral variation hypothesis

Forests cover about 30% of the Earth surface, they are among the most biodiverse terrestrial ecosystems and represent the bulk of many ecological processes and services. The assessment of biodiversity is an important and essential goal to achieve but it can results difficult, time consuming and expensive when based on field data. Remote sensing covers large areas and provides consistent quality and standardized data, which can be used to estimate species diversity.

A simple translation from indices of species diversity to indices of phylogenetic diversity

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.

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