Significant part of not cultivated area of Hungary is not suitable for agricultural utilization because of industrial
pollution. Technologies of biorefinery make reutilization of contaminated areas possible. Biomass of plants
produced on polluted soils can be raw material of valuable products. Applicability of biorefinery was tested on a<...br>heavy metal polluted soil, where the contamination originated from previous mining activity. Complete biomass
utilization was aimed to obtain cosmetic ingredients, pharmaceutical agents, and precursors. During our research
work 88 plant species and varieties were produced and tested for potential utilizable components. Levels of
possible contaminants in these plants were monitored, and amounts of carbohydrates, protein, organic acid and
cellulose were determined as well. Different plant extracts were tested as potential sources of biologically effective
components or as raw materials for lactic acid fermentation. Our results show that biorefinery is a real possibility
for utilization of polluted areas. Numerous plants could be cultivated on contaminated areas without increased
levels of contaminants in their tissues, thus they can be sources of valuable compounds.

Effects of regular K fertilization and liming on the easily extractable K content of a Haplic phaeosem soil determined in 0.01 M CaCl2
and AL (traditional method in Hungary) were examined in the B1740 type of the National Uniformed Long-Term Fertilization Experiments
at Karcag.
Close correlation (r=0.95) was found between the 0.01 M Ca...Cl2 and ammonium lactate - acetic acid (AL) extractable K contents of
soils.
K fertilization increased the amount of 0.01 M CaCl2 and AL extractable K significantly. Liming had different effects on the amounts of
K extracted by these two methods. Liming increased the amount of AL-K and decreased the amount of CaCl2-K. CaCl2 extractable K was in
close correlation with the relative amount of exchangeable K content of the soil (K%) and the agronomic K balance. The results of regression
analysis confirmed that the CaCl2-K characterized K% and the AL-K related to the absolute amount of exchangeable K.
On the basis of the presented results it can be stated that the 0.01 M CaCl2 is able to detect not just the increase of easily extractable K
caused by fertilization and liming but the changing of the rate of the relative amount of exchangeable K.