Do the passerine traits’ dynamic patterns indicate the ecological status of agro-forestry ecosystems? A modelling approach for “Montado” management assessments

Abstract

Context The “Montado”, a human shaped oak agro-forestry dominated landscape of South Western Europe has been experiencing series of changes following the implementation of different agricultural policies. Such changes are responsible for shifting the structure and composition of “Montado” landscape and hence the biodiversity of the system, either by agriculture abandonment or intensification. Traditional oak agro-forestry management practices, which focused on improving the ecological status of a single and common land use (oak agro-forestry), is taken as a conservation paradigm against the perceived changes in the system. Aims We aimed to identify the effect of oak agro-forestry management on “Montado” biodiversity as indicator for ecological status of “Montado” landscape. Methods A recently developed spatially explicit Stochastic Dynamic Methodology (StDM) was applied to model the spatial and temporal patterns of the land use/land cover changes and predict responses in biodiversity patterns, with a focus on passerine functional traits (grassland, woodland and generalist species richness), considering scenarios with and without oak agro-forestry management. Results Model outputs showed that oak agro-forestry management favored the expansion of oak agro-forestry at the expense of other land uses, mainly oak forest and agricultural areas. On the other hand, passerine richness exhibits a gradual decline facing the intensification of oak agro-forestry management practices, with higher declining rate observed for grassland passerine species. Conclusion The oak agro-forestry management does not seem to improve the ecological status of “Montado” landscape, and neither does its abandonment. Hence the conservation paradigm should focus on improving the multi-functionality of the system than merely focusing on a single and common land use