Arsenic is a ubiquitous chemical element, occurring naturally worldwide. Yet due to its global cycle, its concentrations in the marine environment are manifold higher than the terrestrial background and may pose harm to biota. This is especially relevant for the Baltic Sea, which is very susceptible to any kind of pollution. Arsenic transported to the sea is adsorbed on iron oxides or precipitating as flocculating particulates and finally bounded in sediments. Therefore, despite the contemporary emission cuts, the existing pollution remains or constantly circulates in marine habitats. The purpose of the research was to recognize the spatial distribution of arsenic in the surface sediments of the southern parts of the Baltic Sea. The number of 483 samples allowed us to prepare reliable interpolation of arsenic contents in surface sediments. Although arsenic concentrations in the Baltic Sea can be considered low, in particular areas the levels are significantly higher. The observed arsenic concentrations distribution pattern could be mostly explained by natural transportation and accumulation bottom-type distribution.
Study of sediments at gullies mouths conducted in the Suwałki Lakeland (NE Poland) showed that fan sediments are significantly diversified. The changes of sediment type could be linked to forest clearance and farmland expansion. Dating and lithological properties of fan sediments allowed to determine the stages of gully erosion. The research also included studies of sediments accumulated within last 200 years in 6 small gully catchments of different degree of cultivation. Supply of the sediments derived from soil erosion to the gully fans was very limited in catchments where only 15% of the land was cultivated. This process was intensively active in catchments where cultivated land occupied 77% of the area.
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.