Beyond Trivial Relationships: on the Hidden Aspects of Biodiversity

Abstract

The strong correlation found between detailed and simple measures of biodiversity at landscape-scale may suggest that patterns of detailed diversity measures are artifacts (sensu Palmer et al. 2008, this issue). For example the regional pattern of Compositional Diversity (a measure of within-stand structural complexity) can be considered as a correct but trivial result because this pattern is almost completely determined (at least statistically) by the regional pattern of species richness. However, I argue that this interpretation is misleading. Using spatially-explicit individual-based simulations I demonstrate that fine-scale patterns and assembly rules (between a dominant grass and some annual species) significantly affect the dynamics of diversity, and fine-scale constraints are able to generate regional diversity patterns. Simulations illustrate that patterns that seem to be artifacts in a static view might acquire functional relevance in a temporal-dynamic approach. While a static view suggests that variation of fine-scale community attributes (e.g. Compositional Diversity) is explained by the variation of species richness, a dynamic approach shows the opposite. In the long term, variation of species richness is explained by the patterns of fine-scale community organization. I propose the use of mechanistic simulations coupled with the analyses of within-stand variability and spatial dependence of species combinations to reveal otherwise hidden spatiotemporal aspects of biodiversity.