Breeding birds in agro-forest habitat types (Nazzano, Tevere-Farfa Nature Reserve, central Italy): evidencing patterns following a dominance/diversity approach

Abstract

We analysed bird assemblages breeding in three coarse-grained habitat types (cultivated lands, forests and mosaics) by following a dominance-diversity approach. Although we did not observe significant differences in mean values of both species richness and abundance among habitat types, assemblages of cultivated lands showed the lowest values of all diversity metrics. Low values of β-turnover index highlighted low heterogeneity of these anthropic and simple habitat types. The dominance/diversity diagram showed a clear difference between slopes of rank-frequency lines of mosaics and forest habitat types when they were compared to cultivated lands, indicating low species evenness resulting from the high disturbance, typical of agro-ecosystem assemblages. At this scale when we compared mosaics to forest habitats, rank-frequency lines appeared over imposed, suggesting that breeding bird assemblages did not perceive differences between these habitat types.