Environmental Aspect of Potassium Balance in the Geographical and Historical Land of Wielkopolska in 1843–2012

The aim of the study was to assess the intensity of potassium management in agriculture, on the basis of field surface balance in the changing boundaries of Wielkopolska region, with its capital in Poznań. 14 periods were selected at the turn of three centuries XIX, XX and XXI. The surface area and the administrative boundaries have changed quite considerably during this period. Potassium is one of the most important elements which is of great importance not only in the nutrition of crops, but also in human and animal nutrition. Its impact on the environment is not yet fully known. However, agricultural production generates a surplus of this macronutrient, which can be dispersed in the environment. The calculated potassium balance depended largely on the economic and political situation and administration, which affect the degree of intensification of agricultural production in the region. The balance results ranged from -45.47 to 129.71 kg K ha -1 per agricultural land. By 1955, the balance of potassium showed negative values. After this period, the balance recorded was only positive.