EVALUATION OF SPECIES ABUNDANCE MODELS OF TREE STRATA IN A CLOUD FOREST

Abstract

Species-abundance models can be used to detect forest disturbance in ecosystems that had been logged. We compared the fit of four species-abundance models in the tree strata of two stands with different management history in “El Cielo” cloud forest, Tamaulipas, México. Two sampling schemes were tested to evaluate its efficiency in collecting the data needed to fit species-abundance models. The results indicate that both stands show an intermediate succesional grade, between the pionner and climax stages, where the species with middle abundance are the most dominant. The transects were found to be better for collecting the data needed to fit speciesabundance models in the tree strata of this forest. The stand that had previously been selectively logged is currently in an earlier succesional stage compared to the unlogged stand, since the latter fitted a log-normal distribution whereas the former did not. Contrary to some studies claiming that species-abundance models are not good for detecting forest disturbance in sites that had been logged, this study shows that these models can be appropriately used to evaluate whether or not a forest has been disturbed.