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Floodplain forests are among the most endangered ecosystems worldwide, even though they are hotspots for numerous taxa. The abandonment of traditional management and large‐scale timber extraction, such as clear‐cutting, has led to a decline in floodplain forest biodiversity. Retention forestry has the potential to facilitate the implementation of an ecologically sustainable forest management approach. Despite the increasing popularity of this method, its potential for spider diversity conservation, especially its comparison with the widespread practice of clear‐cutting, is still poorly studied.We studied the short‐term effect of forestry treatments (dispersed retention with 60% retained trees and clear‐cutting) on the diversity of ground‐dwelling spiders in the floodplain forests along the Lower Morava (March) and Dyje (Thaya) rivers in the Czech Republic. Spiders were sampled using pitfall traps during 2021 (pre‐harvest year) and 2022 (post‐harvest year).A total of 10,005 specimens from 167 species were recorded. Both forestry treatments simplified habitat structure compared with pre‐harvest conditions, resulting in lower beta‐diversity within sites. However, dispersed retention had higher alpha‐ and beta‐diversity than clear‐cuts, indicating that retention provided a more complex‐structured habitat. Dispersed retention and clear‐cuts hosted distinct spider assemblages with characteristic indicator species. Species typical of open and significantly disturbed habitats preferred clear‐cuts, while species typical of forests and (semi‐) open habitats, including threatened species, showed a preference for dispersed retention.Our results demonstrated, for the first time, that dispersed retention forestry could serve as an effective management tool for conserving the ground‐dwelling assemblages of spiders in floodplain forests. [ABSTRACT FROM AUTHOR]

Th e aim of this study was to investigate the eff ect of selective logging on species richness, composition, and conservation value of epigeic spider community. We studied an initial stage of abandoned coppice restoration in the Děvín National Nature Reserve (Czech Republic). We sampled experimental plots in forest stands with three canopy thinning intensities: strong, moderate, and nonintervention as a control. Altogether, we collected 3,683 adult spiders representing 21 families, 70 genera, and 116 species including 23 red-listed and threatened species. Th e species richness and degree of rareness signifi cantly increased with the intensity of canopy thinning. Ordination analyses showed that species of conservation concern inclined towards plots with strong canopy thinning. However, some conservation-valuable species tended to be associated with non-intervention plots. Our results suggest that the best silviculture practice for spider diversity conservation is a combination of various thinning intensities on a small scale. Such management would support high species richness with the presence of rare and threatened species. Accordingly, we argue that using selective logging and a partial return to traditional coppicing management can be an appropriate strategy for biodiversity conservation in lowland woodlands. [ABSTRACT FROM AUTHOR]

Pesticides constitute a major threat to biodiversity, but our understanding of the complex interactions between local and landscape factors influencing their distribution in agroecosystems remains limited. We conducted a pioneering study where we screened spiders, rodents, plants and soils for multiple pesticide residues in perennial crops (orchards and vineyards) managed under organic (N = 8) and integrated pest management (N = 8) systems. We then quantified the proportional representation of major habitat types in surrounding landscapes. Additionally, we conducted interviews with farmers to gain precise insights into pesticide applications. We expected that landscape factors would be more important for mobile entities (i.e. spiders and rodents), while management type would be relatively more important for the sedentary entities (i.e. soils and plants). We detected various pesticides within studied crop types, including several forbidden in the European Union. We found that pesticide distribution in spiders was influenced by the proportion of semi‐natural habitats in the landscape, with pesticide concentration decreasing as the proportion of semi‐natural habitats increased. Additionally, we observed that the spectrum of pesticides in spiders increased with the dominance of web‐building spiders. In contrast, pesticide levels in rodents were not affected by either landscape composition or local management type. For plants, pesticide distribution was affected by the proportion of forests and shrublands and, to some extent, by local management practices. In the case of soil, pesticide distribution was primarily determined by local management. This study marks an effort in demonstrating that both local and landscape factors play crucial roles in shaping pesticide distribution within perennial crops. Importantly, the relative importance of these factors varied across the four matrices investigated. Synthesis and applications: To comprehend the factors that determine pesticide distribution in crops, it is crucial to monitor diverse ecosystem components rather than focusing on a few model species. This approach underscores the necessity for ecologically sensitive management at landscape scale. Such management should involve the preservation and enhancement of (semi)natural habitats around crops. These combined insights can form the foundation for conservation and management initiatives aimed at mitigating the impact of pesticides on biodiversity within crops. [ABSTRACT FROM AUTHOR]

Th e aim of this work was to assess the eff ect of stand age and type of forest management on the species richness and abundance of spiders, ground beetles, centipedes, millipedes and woodlice. Th e arthropods were sampled in four treatments – clearings, young, middle-aged and old forest stands. Th e eff ect of management was evaluated for clearings and old forest stands. Clearings and older stands hosted the highest species richness for most of the studied groups of arthropods. On the contrary, the lowest species richness was found mainly in young stands. Our results emphasized the high importance of uneven-aged silviculture. Most species were found in clearings without mechanical soil preparation. Th erefore, mechanical soil preparation is not suitable for the studied groups of arthropods. Responses to the management of the old stands varied for diff erent arthropod groups. It is necessary to limit the large-area milling of clearings and maintain continuity of both commercial and non-interventional old forest stands. [ABSTRACT FROM AUTHOR]

Prey selection by generalist predators can be highly dynamic depending on the prey community structure. However, the dynamics of prey selection at the stage of prey entrapping are rarely investigated in trap-building predators, probably because their traps have been previously considered to intercept mobile prey proportionally to its availability in environment. Here we investigated the dynamics of prey selection by the orb-weaving spider Gasteracantha hasselti (Araneidae) depending on the composition of the available prey in tropical lowland forests located in north-eastern Thailand. We found that Gasteracantha captured a wide variety of prey but selected, on average, mostly Coleoptera and Diptera. The selectivity of Gasteracantha's webs for Coleoptera was constant across the changes in overall prey availability and prey composition. The web selectivity for Hemiptera decreased rapidly with increasing relative densities of Hemiptera in the environment. The selectivity for Diptera and Hymenoptera increased and decreased, respectively, with their absolute densities in the environment. The relative selectivity of Gasteracantha's traps for a particular prey type was driven by the presence and density of the highly selected prey rather than overall prey density. The results show that the selectivity of Gasteracantha's traps for prey had both fixed and dynamic components and the dynamic component was determined by the relative as well as absolute densities of the particular prey types in the environment. [ABSTRACT FROM AUTHOR]

The management practices in agroecosystems can alter the community structure of pests' natural enemies, which can consequently disturb their biocontrol function. Here, we investigated how organic or conventional farming influence the community structure of arthropod predators (spiders, coccinelids, anthocorids, ants) in orchards. The three conventional orchards studied were plum tree monocultures where mainly fungicides were applied. The three organic orchards studied were dominated by plum trees with admixture of apple trees and no agrochemical was applied. We found that management significantly affected only spiders that were less abundant in the conventional orchards than in the organic orchards. In addition, the conventional management resulted in reduced species density and altered the community composition of spiders. The conventional management reduced the functional dispersion of spider body size, which may narrow the size-spectrum of pests that could be reduced by spiders. The conventional management also reduced abundances of foliage hunters and space-web spiders. Since these spiders are effective against various insect pests, the conventional management of applying fungicides might result in increased crop damage via increased insect pests. [ABSTRACT FROM AUTHOR]