RESUMO
This work attempts to find the reasons for the rather limited range of occurrence of Cheilotoma musciformis in Poland, based on soil properties, which affects both the plant cover and the entomofauna. The aim of the study was to assess the influence of soil enzyme activity on the occurrence of Ch. musciformis in xerothermic grasslands in Southern Poland. The sites inhabited by the beetle were most often extensively grazed by farm animals or had recently been cleared of bushes. The control plots were in wasteland. The soils of most sites with Ch. musciformis were characterized by significantly higher activity of the tested enzymes and higher content of total organic carbon and total nitrogen, as well as lower pHKCl compared to the control sites. The higher enzymatic activity of soils in sites with the beetle than in the control sites may indicate the dependence of the occurrence of this beetle on the presence of patches of extensively grazed xerothermic grasslands. Grazing influences the behavior of preferred host plant species. Therefore, when planning active protection of xerothermic grasslands inhabited by Ch. musciformis, changes in the biochemical properties of the soil and vegetation structure should be taken into account.
RESUMO
This study assessed the effects of road-related alteration of substrate, including increased salinity, on vegetation along a meridional gradient in Fennoscandia. Vegetation community composition were surveyed in 29 randomly selected 1-m(2) sized roadside plots. Number of plant species and plant cover (%) on the plots were positively interrelated (p < 0.0001). Both variables also decreased towards the north and with increasing coarseness of the substrate. Canonical correspondence analysis (CCA) indicated that roadside vegetation diversity and composition were most related to the importance of the road (i.e. its size and traffic intensity) and substrate pH. Road importance affects plant dispersal, whereas substrate pH was found to be a factor limiting growth. CCA indicated also that vegetation composition was affected by the meridional gradient and by the substrate salinity; both substrate salinity pH and salinity were not related to meridional gradient. Our results indicate that roadside vegetation diversity and composition is driven by natural and anthropogenic factors.