Calcium and magnesium uptake with the yield of meadow vegetation in relation to their content in atmospheric precipitation, ground water and soil solution / Pobranie wapnia i magnezu z plonem roślinności łąkowej na tle ich zawartości w opadzie atmosferycznym, wodzie gruntowej i roztworze glebowym

The question was how and under which conditions the concentration and load of calcium and magnesium in atmospheric precipitation, ground water and soil solution may affect their uptake by vegetation in a managed meadow. The answer was based on results of Ca and Mg determinations in atmospheric fallout near Falenty, and in soil waters from two long-term meadow experiments on mineral soils situated in Masovian Province. Obtained results showed a complex effect of Ca and Mg deposition and associated effects of these components in ground water and soil solution on their uptake by plants due to fertilisation effect, harvesting and other factors of human impact. No distinctly positive effect was found of the increased deposition of Ca with atmospheric fallout on its uptake by plants on a long term basis. Such an effect was demonstrated for Mg load but only in very acidic soil. Under favourable physical and water conditions and at weakly acidic soil pH this effect was negative. The enrichment of ground water in Ca was accompanied by the increase of its uptake by plants and, at the same time, by the decrease of Mg uptake from very acidic soil. Under such soil pH, decreased Ca uptake was associated with its higher concentration in soil solution. Neutralization of soil acidity facilitated the increased Mg concentration in soil solution and its decreased uptake by plants. Obtained results inspire to undertake similar studies in natural grassland ecosystems and in the so-called lands of ecological use.