<abstract xmlns="http://www.w3.org/1999/xhtml"> The influence of six different crop sequences on the dynamics of topsoil available and fixed potassium (Kavail and Kfix) was studied within a 4-year period at 6 sites of different soil and climatic conditions. The highest K off takes were recorded for 3-year alfalfa / clover cropping followed by winter wheat (-151 kg K/ha/year) and for the crop sequence including one year of sugar beet / potato (-0124 kg K/ha/year). Kavail and Kfix were significantly decreased especially at crop sequence with alfalfa / clover cropping, compared to other crop sequences. At three sites of lower Kfix content (340-830 mg K/kg), differences in Kavail and Kfix between crop sequences were more frequent, whereas almost no significant differences between treatments were observed at sites of higher Kfix content (1,000-1,380 mg K/kg). Changes of both K forms and K budget correlated significantly at sites of lower Kfix content. At these sites, Kavail decreased at the rate of 0.045 mg K per 1 kg/ha of K offtake; the rate of Kfix decrease was 0.059 mg K per 1 kg/ha of K offtake. At sites of higher Kfix, no significant relation between K forms and K budget was observed. The results show an importance of Kfix as a K source in intensive agricultural systems with low or no K inputs.</abstract>

The influence of six different crop sequences on the dynamics of topsoil available and fixed potassium (Kavail and Kfix) was studied within a 4-year period at 6 sites of different soil and climatic conditions. The highest K off takes were recorded for 3-year alfalfa / clover cropping followed by winter wheat (-151 kg K/ha/year) and for the crop sequence including one year of sugar beet / potato (-0124 kg K/ha/year). Kavail and Kfix were significantly decreased especially at crop sequence with alfalfa / clover cropping, compared to other crop sequences. At three sites of lower Kfix content (340-830 mg K/kg), differences in Kavail and Kfix between crop sequences were more frequent, whereas almost no significant differences between treatments were observed at sites of higher Kfix content (1,000-1,380 mg K/kg). Changes of both K forms and K budget correlated significantly at sites of lower Kfix content. At these sites, Kavail decreased at the rate of 0.045 mg K per 1 kg/ha of K offtake; the rate of Kfix decrease was 0.059 mg K per 1 kg/ha of K offtake. At sites of higher Kfix, no significant relation between K forms and K budget was observed. The results show an importance of Kfix as a K source in intensive agricultural systems with low or no K inputs.

Effect of Potassium Budget on Evolution of Soil Potassium in Different Crop Sequences and Site Conditions

Agriculture (Pol'nohospodárstvo)

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

The influence of six different crop sequences on the dynamics of topsoil available and fixed potassium (Kavail and Kfix) was studied within a 4-year period at...

Effect of Potassium Budget on Evolution of Soil Potassium in Different Crop Sequences and Site Conditions

Published Online: Mar 04, 2015

Page range: 121 - 131

Received: Nov 18, 2014

DOI: https://doi.org/10.1515/agri-2015-0001

Keywords
fertilisation, nutrients, budget, balance, non-excha ngeable potassium

© by Mikuláš Madaras

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Effect of Potassium Budget on Evolution of Soil Potassium in Different Crop Sequences and Site Conditions

Published Online: Mar 04, 2015

Page range: 121 - 131

Received: Nov 18, 2014

DOI: https://doi.org/10.1515/agri-2015-0001

Keywordsfertilisation, nutrients, budget, balance, non-excha ngeable potassium

© by Mikuláš Madaras

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Keywords
fertilisation, nutrients, budget, balance, non-excha ngeable potassium