Suchergebnisse

AbstractBats, as exceptionally long-lived small mammals, are at particular risk of metal poisoning due to the tendency of metals to bioaccumulate throughout their lives. In our study, we investigated the general question of how trace metal concentrations change with age in different bat tissues on the example of Pipistrellus kuhlii lepidus, which lives for years in one area and is strongly associated with urban environments. To determine the exact age of the individuals, osteochronology was applied, counting the number of dentine rings in cross-sections of the upper canine tooth of each individual. The age of 57 individuals of P. kuhlii lepidus, representing ca. 10% of the colony, was identified. Whole internal organs (liver, kidneys, lungs, and forearm bones) and samples of external tissues (fur and wing membrane) were analyzed for concentrations of Cd, Cu, Pb, and Zn using atomic absorption spectrometry. We found that concentrations of Cd, Pb, and Zn, but not Cu, increase with the age of the bats, but in relatively unpolluted areas, metal concentrations do not reach the level which can cause chronic adverse effects. Nevertheless, due to the confirmed accumulation of metals in bat tissues with age, toxic effects can be expected in older individuals in areas where trace metal concentrations are elevated.

The ELONTA project aimed at understanding the relationships between landscape structure, source-sink dynamics and the risk of pesticide use for Non-Target Arthropods (NTAs). It also investigated the effectiveness of introducing two landscape-based mitigation measures: grassy field boundaries and unsprayed field margins. The project used a model NTA species, Bembidion lampros, a small, univoltine, spring-breeding carabid beetle that is common in temperate European agricultural landscapes. The project combined high-resolution dynamic landscape models with advanced spatially-explicit population models to simulate changes in B. lampros population dynamics in agroecosystems. The impact of pesticide use on B. lampros populations and the effectiveness of mitigation measures were assessed in a set of 611 study plots of 10x10 km2 in Brandenburg and Lower Saxony regions, varying in landscape and farmland heterogeneity. Our analysis showed that beetle populations were better supported in more diverse and heterogeneous landscapes with a high proportion of herbaceous semi-natural habitats and permanent pastures. The negative impact of pesticide use was greater in more homogeneous landscapes with low initial beetle populations, high arable land coverage and low beetle source habitat coverage. The study showed that grassy field boundaries were a more effective mitigation measure than unsprayed field margins. It also revealed the influence of source-sink dynamics on the effect of pesticide application on B. lampros populations, with significant exclusive off-field effects that persisted despite mitigation measures. Landscape management in agroecosystems should focus on maintaining and protecting these habitats, especially in highly homogeneous landscapes.