Resumen de Conceptual and statistical problems associated with the use of diversity indices in ecology
Gilbert Barrantes, Luis Sandoval
- español
Los índices de diversidad y en particular Shannon-Wiener, han sido ampliamente utilizados para el análisis de la diversidad a diferentes escalas geográficas y ecológicas. Estos índices de diversidad poseen serios problemas conceptuales y estadísticos, lo que dificulta o hace imposible la comparación de riqueza o abundancia de especies entre comunidades. Aquí describimos los problemas conceptuales y estadísticos asociados al uso del índice de diversidad Shannon-Wiener, y además presentamos métodos estadísticos alternativos que brindan una mayor información biológica de las especies y permiten una mejor comparación entre comunidades.
- English
Diversity indices, particularly the Shannon-Wiener index, have extensively been used in analyzing patterns of diversity at different geographic and ecological scales. These indices have serious conceptual and statistical problems which make comparisons of species richness or species abundances across communities nearly impossible. There is often no a single statistical method that retains all information needed to answer even a simple question. However, multivariate analyses could be used instead of diversity indices, such as cluster analyses or multiple regressions. More complex multivariate analyses, such as Canonical Correspondence Analysis, provide very valuable information on environmental variables associated to the presence and abundance of the species in a community. in addition, particular hypotheses associated to changes in species richness across localities, or change in abundance of one, or a group of species can be tested using univariate, bivariate, and/or rarefaction statistical tests. The rarefaction method has proved to be robust to standardize all samples to a common size. Even the simplest method as reporting the number of species per taxonomic category possibly provides more information than a diversity index value. Rev. Biol. Trop. 57 (3): 451-460. Epub 2009 September 30.
