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We review the current environmental pollution by mercury in the soils of Poland and Lithuania and in the sediments of the Baltic Sea. Mercury is documented to have many negative impacts on the environment as a toxic trace element. In many different chemical forms, it is being released into the environment by both geogenic and anthropogenic activities, with most being released from anthropogenic sources. Methylmercury is considered one of the most toxic forms found in the environment. Mercury levels in sediment and various point sources increased after World War II in the Baltic Sea, which was used as a dumpsite. Previous studies show noticeable differences in total mercury in the Baltic Sea. In the Warta and Odra rivers in Poland, mercury levels are also higher than the background value, though recent findings suggest that river sediments are not the main source of mercury to marine sediments. Concentrations in soils in Poland and Lithuania were below the level of limit values (1 and 1.5 mg/ kg−1 respectively), but Upper Silesia showed concentrations (up to 4.01 mg·kg−1) above the limit values. Furthermore, between 1992 and 2006, mercury levels in Wrocław dropped dramatically. The dominant trees in the area can affect mercury accumulation. No data were available for comparison with the soils in Estonia and Latvia.

Vehicle collisions with animals pose serious issues in countries with well-developed highway networks. Both expanding wildlife populations and the development of urbanised areas reduce the potential contact distance between wildlife species and vehicles. Many recent studies have been conducted to better understand the factors that influence wildlife–vehicle collisions (WVCs) and provide mitigation methods. Most of these studies examined road density, traffic volume, seasonal fluctuations, etc. However, in analysing the distribution of WVC, few studies have considered a spatial and significant distance geostatistical analysis approach that includes how different land-use categories are associated with the distance to WVCs. Our study investigated the spatial distribution of agricultural land, meadows and pastures, forests, built-up areas, rivers, lakes, and ponds, to highlight the most dangerous sections of roadways where WVCs occur. We examined six potential ‘hot spot’ distances (5–10–25–50–100–200 m) to evaluate the role different landscape elements play in the occurrence of WVC. The near analysis tool showed that a distance of 10–25 m to different landscape elements provided the most sensitive results. Hot spots associated with agricultural land, forests, as well as meadows and pastures, peaked on roadways in close proximity (10 m), while hot spots associated with built-up areas, rivers, lakes, and ponds peaked on roadways farther (200 m) from these land-use types. We found that the order of habitat importance in WVC hot spots was agricultural land < forests < meadows and pastures < built-up areas < rivers < lakes and ponds. This methodological approach includes general hot-spot analysis as well as differentiated distance analysis which helps to better reveal the influence of landscape structure on WVCs.

Geochemical and lithological parameters of sapropel in lakes, combined with pollen data and radiocarbon 14C dating, contain a wide spectrum of environmental information. This includes records of fluctuations of water level and changes of conditions of sedimentation, accumulation of organic matter and chemical elements due to climate change, human impacts and other environmental changes. Rising concentrations of hazardous substances in the natural sediments are likely to be a high risk to the natural environment. At the same time, they can greatly reduce opportunities for environmental engineering of lakes. Four lakes with different trophic states and anthropogenic pressures were chosen for this study in Lithuania. Higher concentrations of elements like Cr, Cu and Zn were not only detected in the top most layers of sapropel but also in deeper layers and are attributed to lithogenic association of trace elements in such deep layers. Concentrations of Pb were detected only in upper layers of sapropel which indicates the impact of anthropogenic activity. The main source of heavy metals was multidimensional anthropogenic pollution leading to a biogenic–anthropogenic association of elements. Sapropel with low concentrations of heavy metals exhibits a different inter-association matrix because most of the elements tend to form lithogenic–clastogenic associations.

Abundant resources, natural and organic material – sapropel containing a multitude of different chemical elements has a great potential to be used in different areas, but for now these rich resources are not widely used because of different chemical composition of sapropel research is very few. The article deals with silicon sapropel as a sorbent is able to absorb heavy metals from the solution depending on the time and the concentration of heavy metals in the solution. The sorption studies of heavy metal concentrations were measured in dry sapropel sample using Thermo Scientific Niton® XL2 series of X-ray fluorescence spectrometer (XPS). Also, the heavy metal concentrations in solution were measured by atomic absorption spectrometer AAnalyst 200 (AAS). Get sapropel sorption capacity results are analyzed through absorption capacity curves and Matala ion removal efficiency curves. Also, comparing the results with the initial concentration of heavy metals sapropel and foreign authors used sorbent properties. After thorough research sapropel sorption capacity can be added to the knowledge of sapropel properties utilization. Article in Lithuanian. Silicinio sapropelio naudojimas sunkiesiems metalams šalinti iš tirpalo Santrauka Gausūs natūralios organinės medžiagos – sapropelio, kurio sudėtyje yra daug įvairių cheminių elementų, – ištekliai turi didelį potencialą būti panaudoti įvairiose srityse. Šiuo metu šie gausūs ištekliai nėra plačiai naudojami, nes atlikta labai nedaug sapropelio įvairios cheminės sudėties tyrimų. Straipsnyje nagrinėjama silicinio sapropelio kaip sorbento geba sorbuoti sunkiuosius metalus iš tirpalo, priklausomai nuo laiko ir sunkiųjų metalų koncentracijos tirpale. Atlikus sorbcijos tyrimus, sunkiųjų metalų koncentracijos matuotos sausame sapropelio mėginyje, naudojant Thermo Scientific Niton® XL2 serijos rentgeno spindulių fluorescencinį spektrometrą (RFS). Taip pat sunkiųjų metalų koncentracijos matuotos tirpale naudojant atominės absorbcijos spektrometrą AAnalyst 200 (AAS). AAS tyrimus atliko atestuota UAB „Vilniaus vandenys“ geriamojo vandens laboratorija. Gauti sapropelio sorbcinės talpos tyrimų rezultatai analizuojami sudarant adsorbcinės talpos kreives bei metalo jonų pašalinimo efektyvumo kreives. Taip pat rezultatai buvo palyginti su pradine sunkiųjų metalų koncentracija sapropelyje ir užsienio autorių naudotų sorbentų sorbcinėmis savybėmis. Atlikus tyrimus gautas 97,4 % sorbento-sapropelio pašalinimo efektyvumas sorbuojant šviną ir 97,24 % sorbuojant cinką. Tyrimų rezultatų paklaida patikrinta lyginant išmatuotą sorbento talpą su apskaičiuotąja. Švino adsorbcinės talpos paklaida siekia 4–9 mg/kg, o cinko 1–14 mg/kg. Reikšminiai žodžiai:sunkieji metalai, Pb, Zn, sapropelis, sorbcinė talpa.