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The impact of mining activities on spider (Araneae) diversity and assemblages was studied in two abandoned mine sites in Sardinia (Italy), where mining activities started in the middle of the nineteenth century and closed down over a century later. Spider community composition was analysed in dumps, undisturbed forests and scrublands which represent the natural chronosequence following the abandonment of the mining district. The identification of spiders was performed at the lowest taxonomic level possible and differences in abundance, species richness (SR), and functional diversity (FD) were analysed. Nonmetric multidimensional scaling (NMDS) and a permutated multivariate analysis of variance (PERMANOVA) routine were conducted to evaluate the relationships of spider assemblages with land cover, and the indicator species analysis was performed to identify the typifying species. During the entire sampling period, 2312 spiders were captured, and approximately 80% of the total were identified at the species level (79 spider species belonging to 28 different families). No differences in abundance and SR were found, whereas FD, which showed the highest values in forests, significantly differed among sites. A distinct separation among assemblages and a significant effect of the land use on spider assemblages were found (PERMANOVA, R 2  = 0.59, p < 0.001). Twelve species were selected as indicator species. Our results underlined the possibility to consider ground-dwelling spiders as a valuable target group for biomonitoring programmes supporting projects of near-natural restoration and/or technical reclamation of mining sites.

Background: The gypsy moth, Lymantria dispar, is one of the main pests of oak forests worldwide and causes extensive defoliation during its periodic outbreaks. In the Mediterranean region, control of gypsy moth populations in cork oak forests is based on application of Bacillus thuringiensis serovar kurstaki (Btk) formulations. This research investigated the effects of Btk applications carried out in two different population development phases on gypsy moth population dynamics. With this aim, temporal and spatial fluctuation patterns of L. dispar egg density were monitored in cork oak forests treated with Btk applications from 2004 to 2009 in Sardinia (Italy)., Results: Applications undertaken during the progradation and culmination phases protected the oak canopies equally in the year of application, leading to a similar decrease in pest population density in the following year. However, the medium-term effectiveness of Btk differed between the two application timings, because only applications in the culmination phase caused a gradual decrease in L. dispar infestations throughout subsequent years. By contrast, when the application was undertaken during the progradation phase, population density increased again after 2-3 years. Moreover, Btk applications in the culmination phase reduced significantly the number of years in which gypsy moth density was damaging compared with those done in progradation., Conclusions: Our results indicate that Btk applications during the culmination phase were more effective than those in the progradation period, because application in the latter case did not suppress the population, but only postponed the outbreak peak by 2-3 years. © 2019 Society of Chemical Industry., (© 2019 Society of Chemical Industry.)