The Effect of Climate and Human Pressures on Functional Diversity and Species Richness Patterns of Amphibians, Reptiles and Mammals in Europe

The ongoing biodiversity crisis reinforces the urgent need to unravel diversity patterns and the underlying processes shaping them. Although taxonomic diversity has been extensively studied and is considered the common currency, simultaneously conserving other facets of diversity (e.g., functional diversity) is critical to ensure ecosystem functioning and the provision of ecosystem services. Here, we explored the effect of key climatic factors (temperature, precipitation, temperature seasonality, and precipitation seasonality) and factors reflecting human pressures (agricultural land, urban land, land-cover diversity, and human population density) on the functional diversity (functional richness and Rao’s quadratic entropy) and species richness of amphibians (68 species), reptiles (107 species), and mammals (176 species) in Europe. We explored the relationship between different predictors and diversity metrics using generalized additive mixed model analysis, to capture non-linear relationships and to account for spatial autocorrelation. We found that at this broad continental spatial scale, climatic variables exerted a significant effect on the functional diversity and species richness of all taxa. On the other hand, variables reflecting human pressures contributed significantly in the models even though their explanatory power was lower compared to climatic variables. In most cases, functional richness and Rao’s quadratic entropy responded similarly to climate and human pressures. In conclusion, climate is the most influential factor in shaping both the functional diversity and species richness patterns of amphibians, reptiles, and mammals in Europe. However, incorporating factors reflecting human pressures complementary to climate could be conducive to us understanding the drivers of functional diversity and richness patterns.

Portfolio of Carry Trade Using Indian Rupees

In this study, we have considered the portfolio of carry trade along with bond and equity. The interior point method and non-dominated sorting genetic algorithm II have been used for optimization. The criteria for the portfolio are the weighted sum of risk and return, utility maximization, diversification ratio and Rao’s quadratic entropy. We find that the interior point method with weighted sum of risk and return gives the best result.

From zero to infinity: minimum to maximum diversity of the planet by spatio-parametric Rao’s quadratic entropy

AimThe majority of work done to gather information on Earth diversity has been carried out by in-situ data, with known issues related to epistemology (e.g., species determination and taxonomy), spatial uncertainty, logistics (time and costs), among others. An alternative way to gather information about spatial ecosystem variability is the use of satellite remote sensing. It works as a powerful tool for attaining rapid and standardized information. Several metrics used to calculate remotely sensed diversity of ecosystems are based on Shannon’s Information Theory, namely on the differences in relative abundance of pixel reflectances in a certain area. Additional metrics like the Rao’s quadratic entropy allow the use of spectral distance beside abundance, but they are point descriptors of diversity, namely they can account only for a part of the whole diversity continuum. The aim of this paper is thus to generalize the Rao’s quadratic entropy by proposing its parameterization for the first time.InnovationThe parametric Rao’s quadratic entropy, coded in R, i) allows to represent the whole continuum of potential diversity indices in one formula, and ii) starting from the Rao’s quadratic entropy, allows to explicitly make use of distances among pixel reflectance values, together with relative abundances.Main conclusionsThe proposed unifying measure is an integration between abundance- and distance-based algorithms to map the continuum of diversity given a satellite image at any spatial scale.

Functional diversity on rocky shores of the SW Atlantic: sewage effluents influence and mask the effects of the latitudinal gradient

Rocky shores are a transitional ecosystem between land and marine environments, and, together with other benthic coastal habitats, have a diverse macrobenthic community. Although there is enough information about the taxonomic diversity of Argentinean rocky shores, studies with a functional approach are scarce. We applied biological traits analysis and functional diversity indices to evaluate the geographic variation of the functional diversity of macrobenthic assemblages on rocky shores along a latitudinal gradient in the SW Atlantic (from 37° to 50°S). A total of 11 beaches with rocky hard substrate belonging to 2 biogeographical provinces (Magellanic and Argentinean) were studied during April 2016. The trait composition of macrobenthic assemblages and functional diversity indices (Rao’s quadratic entropy) varied significantly along the Argentinean coast, suggesting that the latitudinal gradient influences the distribution of species with respect to combinations of trait modalities. Rao’s quadratic entropy, species richness, evenness, and Shannon-Wiener diversity showed a pattern with higher values in the sites located in high latitudes. The functional diversity patterns found coincide with the biogeographical provinces. The presence of intertidal sewage effluents considerably influence functional diversity and mask the effects of the latitudinal gradient on the macrobenthic communities on rocky shores.