Exploring cross-taxon congruence between carabid beetles (Coleoptera: Carabidae) and vascular plants in sites invaded by Ailanthus altissima versus non-invaded sites: the explicative power of biotic and abiotic factors

Ailanthus altissima is one of the most global widespread invasive alien species and its effect as habitat transformer requires detailed investigations. In particular, its invasion in natural ecosystems and its effect on local fauna should be evaluated and described. With this purpose, the identification of surrogate taxa would be an important tool in order to define the impact of this invader on different habitats. Here, we evaluated cross-taxon congruence to quantify the strength of plant species composition in predicting multivariate patterns in carabid beetle assemblages, based on data from 20 sites divided in invaded and non-invaded habitats located in the Karst area, North-east Italy. We considered the habitat type (representing vegetation stages from grassland to forests) in order to evaluate the impact of A. altissima on carabid beetles along the vegetation succession. We found 28 carabid beetles and 173 plant species. Our analyses showed that plant species composition had a valuable predictive accuracy, based on the interplay among environmental variables, soil parameters and vegetation structure. Native vegetation and habitat type were the most important factors influencing carabid beetles and plant species composition. Furthermore, 33% of the total explained variation of carabid beetles assemblages (variance partition based on RDA analysis) was due to the independent effect of environment. We proved cross-taxon congruence between carabid beetles and plants along the successional gradient of vegetation (habitat type). In particular, we attested that both communities present more species differentiation among non-invaded vegetation and, in the meantime, in plots were A. altissima was present, anthropic and disturbed plants and carabid beetles species were prevalent. As a conclusion, plants can be effectively used as a surrogate taxon in the evaluation of the effect of A. altissima invasion in the Karst area

From childhood socio-economic position to adult educational level - do health behaviours in adolescence matter? A longitudinal study

Background Our interest was in how health behaviours in early and late adolescence are related to educational level in adulthood. The main focus was in the interplay between school career and health behaviours in adolescence. Our conceptual model included school career and health-compromising (HCB) and health-enhancing (HEB) behaviours as well as family background. Two hypotheses were tested: 1) the primary role of school career in shaping educational level in adulthood (an unsuccessful school career in adolescence leads to HCB and not adopting HEB and to low educational level in adulthood); 2) the primary role of health behaviours (HCB and not adopting HEB in adolescence leads to a school career with low education in adulthood). Methods Mailed surveys to 12 to18 year-old Finns in 1981–1991 (N=15,167, response rate 82%) were individually linked with the Register of Completed Education and Degrees (28 to 32-year-olds). We applied structural equation modeling to study relations of latent variables (family SEP, family structure, school career, HCB, HEB) in adolescence, to the educational level in adulthood. Results Standardized regression coefficients between school career and health behaviours were equally strong whether the direction was from school career to HEB (0.21-0.28 for 12–14 years; 0.38-0.40 for 16–18 years) or from HEB to school career (0.21-0.22; 0.28-0.29); and correspondingly from school career to HCB (0.23-0.31; 0.31-0.32) or from HCB to school career (0.20-0.24; 0.22-0.22). The effect of family background on adult level of education operated mainly through school career. Only a weak pathway which did not go through school career was observed from behaviours to adult education. Conclusions Both hypotheses fitted the data showing a strong mutual interaction of school achievement and adoption of HCB and HEB in early and late adolescence. Both hypotheses acknowledged the crucial role of family background. The pathway from health behaviours in adolescence to adult education runs through school career. The interplay between behaviours and educational pathways in adolescence is suggested as one of the mechanisms leading to health inequalities in adulthood.</p

Ants as indicators for vertebrate fauna at a local scale: an assessment of cross-taxa surrogacy in a disturbed matrix

We examined the spatial fidelity in the pattern in species richness, abundance and composition of ants, birds, mammals and reptiles in a Eucalyptus vegetation type in Australian tropical savanna woodland. We sampled 32 sites representing intact (uncleared) vegetation, and three treatments of different clearing age (2, 12 and 18 years). We investigated whether each fauna taxon could act a surrogate for pattern in the other, and whether they responded in parallel to time since clearing. Reptiles and mammals were\ud combined into a single group. The correlation between taxa was low for abundance (the best being between rept/mamm and ant abundance R = 0.34) and moderate for species richness (varied from 0.36 to 0.44). Mantel tests identified a moderately strong relationship between bird and rept/mamm composition (R = 0.48). Recent clearing (2–12 years)\ud depleted both abundance and species richness of the vertebrate fauna, whereas ant abundance spiked. Ant species richness was consistent over time since clearing. ANOSIM\ud revealed that clearing age was a strong a priori predictor of birds and rept/mamm composition (Global R = 0.48, 0.65, respectively), whereas it was not for ants (Global\ud R = 0.20). Pair-wise comparisons suggested that for birds, rept/mamm, there was consistent changes in composition from intact woodlands to different aged clearing. This was not the case for ants; most distinct variation in composition occurred between treatments of increasing in clearing age (2–18 years R = 0.69, 12–18 years R = 0.65). The results of\ud this study do not support the use of ants as a surrogate of vertebrates at a local scale in a cleared and intact vegetation mosaic. We acknowledge that identification of universal surrogates and indicators are difficult to find, but funding and political expediency that demand rapid solutions to conservation planning necessitate continued investigation of the merits of using surrogate species