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Assemblages of epigeic ground beetles living in Norway spruce forests in north-eastern Poland in three age ranges: young: 20-30 years (A); middle-aged: 40-50 years (B); old: 70-80 years (C) were investigated. In each age category, 4 plots with 5 Barber traps were set up. Ground beetle assemblages were compared in terms of their abundance, species richness, and the Shannon H' index value. Quantitative ecological description of the carabids captured in the analysed age-classes of Norway spruce forests was performed, and the values of the mean individual biomass (MIB) were calculated. To determine the correlation between mean individual biomass and abundance of various ecological groups of carabid beetles, the Spearman rank correlation coefficient was calculated. The assemblages of ground beetles living in the Norway spruce forests in north-eastern Poland were characterised by quite large species richness (44 species in total). There were significant differences in species richness among the different ages of Norway spruce forests. The oldest Norway spruce stands (70-80 years old) had a smaller number of species and specimens of ground beetles as well as the highest MIB values in comparison with the younger spruce forests A and B. The results revealed that high MIB values were positively correlated with the presence of large ground beetle species with higher moisture requirements. Lower values of the MIB index were due to the presence of smaller open habitat macropterous species, with the spring type of breeding and associated with open areas. [ABSTRACT FROM AUTHOR]

The influence of chemical plant protection on carabid beetle assemblages was studied in an experiment conducted on fields of sugar beet at the IOR-PIB Experimental Station in Winna Góra, Poland. The experiment was composed of a block of control fields (no chemical plant protection treatments) and second block, where plant protection was carried out in compliance with the applicable plant protection program. Ground beetles were caught from May to August/September in four years, using modified Barber traps. As a result of the study, 11 881 specimens belonging to 52 species of Carabidae were collected. The most numerous species were: Harpalus rufipes, Pterostichus melanarius, Calathus ambiguus and Bembidion properans. Overall, our results demonstrate that the application of chemical plant protection treatments decreased the abundance of carabid beetles in sugar beet fields, but had no effect on species richness. The use of pesticides induced changes in some life traits of Carabidae fauna. After a pesticide application, the abundance of macropterous hemizoophages and medium carnivores with the autumn type of breeding decreased, whereas the abundance of small carnivores increased. [ABSTRACT FROM AUTHOR]

This study, concerning the epigeic fauna of carabid beetles (Coleoptera; Carabidae), was conducted in the north-east of Poland, in an area which is part of the Dąbrówka Forest Subdistrict and has been included in the "Small water retention program for the Province of Warmia and Mazury in 2006-2015". The purpose of the study was to assess the impact of the water retention implemented within the framework of the above program on assemblages of ground beetles. These insects are highly sensitive to any anthropogenically induced transformations. This analysis was based on the interactions among the analyzed insects caused by changes occurring in their habitat. During the 3-year study, 5,807 specimens representing 84 species were captured. The water storage had a significant influence on the structure of the Carabidae assemblages. Before the earthworks were constructed for the project, the beetle assemblages had comprised a large group of xerophilous species, whereas after the small retention reservoirs had been created, an increase in the contribution of hygrophilous species was noticed. The results indicate that the retention works cause alterations in the water and environmental conditions of the habitats, and thereby effect changes in the composition of Carabidae assemblages. Moreover, modification in water relations within a habitat causes long-term changes in the structural and functional diversity of the beetles. [ABSTRACT FROM AUTHOR]

Spiders (Araneae) create abundant and diverse assemblages in many agroecosystems, where they play a crucial role as the main group of predators and pest controllers. However, seasonal disturbance in the agricultural environment (e.g., harvesting or ploughing) affects spider assemblages. The main aim of this research was to compare assemblages of Araneae colonising cereal fields cultivated under two different systems of soil tillage: conventional with ploughing and non-inversion tillage. The research covered plantations of triticale, wheat, and barley, situated in northeastern Poland. Ground-dwelling spiders were captured into modified pitfall traps filled up to 1/3 height with an ethylene glycol solution. In total, 6744 spiders representing 67 species classified in 13 families were caught. The traps were emptied every two weeks from the end of April until the end of July. A total of 2410 specimens representing 55 species were captured in the fields with simplified cultivation, while the remaining 4334 specimens representing 49 species were trapped in conventional fields where ploughing was performed. The Shannon diversity (H') and evenness (J') indices reached higher values in the fields without ploughing. According to IndVal Erigone, dentipalpis and Bathyphantes gracilis were signifi-cantly characteristic (p < 0.05) for non-inversion soil tillage, whereas six species, Oedothorax apicatus, Pardosa prativaga, Pardosa paludicola, Pachygnatha clerki, Dicimbium nigrum brevisetosum, and Clubiona reclusa, were typical of soil tillage with ploughing. The research showed that simplification of soil tillage in cereal fields improves the biodiversity of arachnofauna in agricultural ecosystems. The use of conventional tillage systems with ploughing promotes agrobiontic species of the families Linyphiidae and Lycosidae. [ABSTRACT FROM AUTHOR]