Dear friends, I am thinking on the interpretation of the results of the variation partitioning of community composition by means of RDA. Despite all drawbacks of the approach, it continues as an important tool to access the global effects of environmental factors and space on the variance of species abundances in communities. However, I think there are two somehow different interpretations of the results.
I would like to know what do you think about it, in order to make it clearer. The more classic interpreation for significant pure environmental and pure spatial effects (the most common result) is that the environmental effects represent species sorting (SS) by abiotic factors (niche related) while the spatial effects represent dispersal limitation, possibly linked to neutral dynamics, aside non-measured abiotic factors. In his review of these results, however, Cottenie (2005, Ecology Letters) proposed a classification of matacommunities based on variation partitioning results, and interpreted significant pure environmental + pure spatial fractions as indicative of Species Sorting + Mass Efffects metacommunity dynamics. Do you know why would it not be indicative of Species Sorting + Neutral Dynamics? What would be the reasoning for the differentiation between Mass effects and Neutral Dynamics? My first thought was that the pure spatial component would be indicative of dispersal limitation effects. This would be nearer neutrality than mass effects, since mass effects represent the opposite of dispersal limitation, wright? There is an overflow of dispersal not limitation. Thank you very much in advance for any thoughts, All the best, Alexandre Dr. Alexandre F. Souza Professor Adjunto II, Departamento de Ecologia Universidade Federal do Rio Grande do Norte (UFRN) Caixa Postal 1524, Campus Universitario Lagoa Nova CEP 59078-970 http://www.docente.ufrn.br/alexsouza Curriculo: lattes.cnpq.br/7844758818522706
