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Effect of Different Management Practices on Ground Beetle (Coleoptera : Carabidae) Assemblages of Uphill Grasslands

Twardowski J. P., Pastuszko K., Hurej M., Gruss I.

Polish Journal of Ecology

2017

Vol. 65, nr 3

400--409

Grasslands, especially those under ecological management (i.e. mowing, and grazing without fertilizers and chemicals), have significant importance for many arthropods, including ground beetles. We studied the abundance and species diversity of Carabidae of four uphill grasslands (West Sudety Mountains, Poland) under different management intensity: cattle grazing (one or four times per year), mowing, and alternatively managed (grazing/mowing). Beetles were collected using pitfall traps during three whole grazing seasons, i.e. from April to October in 2007-2009. The most frequent species of beetles, on each of the plots, were predators Poecilus cupreus, Calathus fuscipes and Nebria brevicollis. Sixtyfour ground beetle species were found altogether. Species richness ranged from 42 to 47, with the mean number of individuals per trap day-1 from 0.006 to 0.018. In the years of the study the number of ground beetles and their species diversity were higher on meadows mown once per year and alternatively managed grasslands as compared with grazed sites. Therefore, the simplified, organic way of agricultural production with reduced mowing or moving combined with grazing can be considered as appropriate in preserving the biodiversity of the grasslands in mountainous regions.

Bumblbebees (Bombidae) along pollution gradient - heavy metal accumulation, species diversity, and Nosema bombi infection level

Szentgyorgyi H., Blinov A., Eremeeva N., Luzyanin S., Grześ I., Woyciechowski M.

Polish Journal of Ecology

2011

Vol. 59, nr 3

599-610

Pollinator crisis (Kearns et al. 1998) and its possible causes has become a worldwide issue during the last two decades. Although pollution is among the possible causes of the widely observed pollinator loss, it is still poorly investigated and no studies are known, so far to test the effects of heavy metal contamination in bumblebees (Bombidae) - the second most important group of managed pollinators after honey bees (Apis mellifera Linneaus). We have tested heavy metal (Pb, Cd, and Zn) accumulation, species diversity and parasite load (focusing on the common Nosema bombi Fantham and Porter, Microsporidia: Nosematidae) in bumblebees. For this purpose, we have chosen three heavy metal gradients (Guryevsk, Belovo and Olkusz) and two additional control sites (Kouznetskiy Alatau and Gornaya Shoria). All gradients were approximately 20 km long, starting in close proximity (1.3 km or less) of an active zinc or metal smelter, and each consisting of 5 sites located on semi-natural or drgraded meadows in various distance from the smelter. On each site min. 50 bumblebees were caught by sweep nets, each individual identified to species level and next, its abdomen homogenized and used for assessment of N. bombi infestation. Heavy metal levels in soil of the tested gradients varied between (Pb: 13.6-814.2 mg kg[^-1], Cd: 0.14-20.3 mg kg[^-1], Zn: 67.0-889.3 mg kg[^-1]) Bumblebees accumulated Pb and Cd (Pb: 0.21-3.3 mg kg[^-1], Cd: 0.002-0.069 mg kg[^-1]) in their bodies. The content of these metals in bumblebee bodies correlated with their content in soil (Pb: P <0.01, Cd: P = 0.002). However, no correlation was found between the Zn contents in bumblebees (Zn: 74.7-81.9 mg kg[^-1]) and the soil. We have also found that the metal contents in soil or in the bodies of bumblebees caused no changes in species diversity or dominance on polluted sites, irrespective of type and the level of contamination. The variation of Shannon diversity (H.), as well as Simpson.s diversity (D) were similar in all studied sites and ranged from 0.543 to 0.81 and from 0.152 to 0.484 respectively. The proportion of infected individuals was generally not higher than 0.29 and did not differ significantly among the studied sites. Incidentally, based on variation in the small subunit ribosomal RNA (SSU-rRNA) gene, we have found a new strain of Nosema bombi in the Kouznetskiy Alatau and Gornaya Shoria (West Siberia, Kemerovo Region) samples. The new small subunit RNA sequence in the new strain of N. bombi was named N. bombi WS2 (West Siberia) SSU rRNA. Based on the obtained results we conclude, that bumblebees can withstand or even successfully deal with heavy metal contamination at certain levels.