Environment, in Foods and Living Organisms

The rubidium content of water is subjected to the same rules as rubidium transfer from rocks to the soil and from soils into plants. On average, water from granite, gneiss and phyllite contains 14-18 pgL while that from Pleistocene and Holocene formations (diluvial sands) and Muschelkalk proved to be particularly poor in rubidium (3.1-3.5 pgL Y The rubidium contents in different soils and waters are mainly determined by the rubidium concentrations in the source material for soil formation. Anthropogenic influences on the rubidium content in the soil and water are hardly probable (Anke and Angelow 1995). 

The rubidium contents of drinking water in Germany were investigated systematically, and a mean rubidium concentration of 11 pgL and a median of 8.1 pgL were established (Anke et al. 1997b). The water of Lake Balaton in Hungary accumulated much higher rubidium concentrations (94 to 1100 pgL ) (Kovacs etal. 1985). 

The rubidium content of the flora is species-specific, and is seen to vary with the age of the plants, the rubidium concentration of the soils, and their pH value. An acid pH value of the soil supports rubidium uptake (Tyler 1983, 1997, Tyler and Zohlen 1998). 

The influence of the geological origin of the biotope on the rubidium content of the flora was investigated by means of indicator plants in Central Europe. The plants employed were red clover (field and meadow varieties), rye and wheat at definite stages of development. In order to illustrate the influence of the site on the species-specific rubidium content of the four indicator 

The clay minerals of these formations bind the rubidium of the water during flooding. Slate weathering soils (relative number 48) still deliver more bioavailable rubidium than the formations of the Quaternary (loess, boulder clay, diluvial sands), from which rubidium was washed out by 

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