Analysis and modelling of Lymantria dispar L. metapopulation dynamics in Sardinia

Sustainable forest management could take advantage from knowing the ecological mechanisms underlying provisioning and regulating ecosystem services. The gypsy moth, Lymantria dispar (L.) (Lepidoptera: Lymantriidae), is one of the main oak forest defoliators in the Holarctic Region, and its outbreaks may disrupt ecosystem mechanisms at the basis of forest productivity and regulation. Most of the analysis and modelling approaches on gypsy moth population dynamics have been applied to a continuous spatial dimension. These approaches do not account for the possible role of highly fragmented forest stands on pest dynamics. The objective of this contribution is to analyse the influence of the fragmented landscape structure in Sardinian forest areas on gypsy moth spatiotemporal dynamics. The performed analysis is based on: a) the evaluation of spatial synchrony of population dynamics to account for connectiveness among local populations in single patches, b) the parameterization of spatially explicit metapopulation models to describe the forest pest metapopulation dynamics. The estimated metapopulation models display interesting properties that could be useful in defining the specific metapopulation dynamics pattern at forest district level. The proposed approach could be further developed and applied to the evaluation of management strategies of the forest pest.