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Landfills have been identified as potential sources of heavy metal pollution of the environment. The municipal solid waste Łubna landfill is one of the largest landfills in Poland. Its impact on heavy metal pollution (Cd, Pb, Zn, Cu, and Cr) of groundwater, soil and plants has been thoroughly evaluated. Elevated levels of contamination have not been recorded in the vicinity of the landfill. The concentrations of heavy metals in soil from the vicinity of the landfill were similar to the geochemical background levels for the forest and farming soils of central Poland. The concentrations of heavy metals in European goldenrod (Solidago virgaurea L.) and grasses (Poaceae) did not exceed the baseline concentrations and did not indicate environmental pollution by heavy metals. The levels of the metal concentration in groundwater did not exceed the standards established for water intended for consumption.

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The perennial ryegrass is the species widely used in Europe as forage as well as for creating lawns in urban areas. Unfavourable light conditions in cities are the principal reason of improper growth and functioning of grass communities. The aim of our work was to answer the following questions: what is the adaptive ability of photosynthetic apparatus of perennial ryegrass varieties to long-term reduction of solar radiation and which of the tested varieties has the best properties to be used for grassland establishment under reduced light conditions. A two-factor experiment was conducted with three varieties and three shading variants. Measurements of chlorophyll a fluorescence were provided, and the basic assessed parameters were: minimal fluorescence (F 0 ), maximal fluorescence (F m ), variable fluorescence (F v ) and maximal photosynthetic efficiency of photosystem II (F v /F m ). Gas exchange was also measured. We explored the differences between the selected varieties in terms of their photosynthetic apparatus adaptation to light conditions. During May, all varieties were characterized by increase in minimal and maximal fluorescence levels under reduced light. The most significant changes were noticed for variety 'Taya'. During following months, a trend of decline in photosynthetic efficiency was observed for this variety. For this variety the most significant changes of CO 2 were also noted. The stomatal conductance was not affected by shading. On the basis of our results, we have assumed that each variety is unique in terms of threshold values and demand for light.

The present and future air contamination by mercury is and will continue to be a serious risk for human health. This publication presents a review of the literature dealing with the issues related to air contamination by mercury and its transformations as well as its natural and anthropogenic emissions. The assessment of mercury emissions into the air poses serious methodological problems. It is particularly difficult to distinguish between natural and anthropogenic emissions and re-emissions from lands and oceans, including past emissions. At present, the largest emission sources include fuel combustion, mainly that of coal, and “artisanal and small-scale gold mining” (ASGM). The distinctly highest emissions can be found in South and South-East Asia, accounting for 45% of the global emissions. The emissions of natural origin and re-emissions are estimated at 45–66% of the global emissions, with the largest part of emissions originating in the oceans. Forecasts on the future emission levels are not unambiguous; however, most forecasts do not provide for reductions in emissions. Ninety-five percent of mercury occurring in the air is Hg0—GEM, and its residence time in the air is estimated at 6 to 18 months. The residence times of its HgII—GOM and that in Hgp—TPM are estimated at hours and days. The highest mercury concentrations in the air can be found in the areas of mercury mines and those of ASGM. Since 1980 when it reached its maximum, the global background mercury concentration in the air has remained at a relatively constant level.