ECo: A new measure evaluating the degree of consistency between environmental factors and spatial arrangement of species assemblages

We introduce a measure of Ecological Consistency (ECo) aimed at assessing the importance of environmental factors in determining species distribution. Differently than most available techniques, ECo is targeted towards species assemblages, and takes into account biotic interactions, species abundance and local richness. ECo is defined as the probability that moving a species’ occurrence from an occupied cell in a species per site matrix to an unoccupied one will reduce the ecological consistency of the species. The ecological consistency of a species is measured as the average value of the distances between each possible pair of the species’ occurrences, computed using the environmental values associated with the respective areas of occurrence. To demonstrate the potential of ECo, we report three case studies. The first one offers a direct evaluation of the proposed method, by demonstrating that the ECo index computed using a set of bioclimatic variables on 1000 random matrices of European trees is negatively correlated with the overall ecological specialization of the species included in each matrix (more euryecious species have lower ECo values). The second one, which applies a similar approach to four lists of European terrestrial vertebrates, including mammals, reptiles, amphibians and birds, shows that the method is robust towards differences related to the taxa under study. The third one reports a practical application of ECo, and demonstrates that it significantly correlates with various species traits potentially related to ecological specialization in 50 families of tropical marine fish. These results indicate that ECo can be a valuable tool to investigate macroecological patterns. A software to compute ECo is freely available at http://ecosoft.alwaysdata.net/ECo.

STRONA Giovanni;  FATTORINI Simone;  MONTANO Simone;  SEVESO Davide;  GALLI Paolo;  SAN-MIGUEL-AYANZ Jesus; 

2014-12-19

ELSEVIER SCIENCE BV

JRC87417

1470-160X,   

http://www.sciencedirect.com/science/article/pii/S1470160X14005688,    https://publications.jrc.ec.europa.eu/repository/handle/JRC87417,   

10.1016/j.ecolind.2014.11.033,