engleski

Four-year dynamic of potassium on two sites interpreted by different soil tests

The three soil-K tests were compared using soil and plant samples collected during fertilization and liming experiments in Croatia on very acid dystric luvisol and slightly alkaline calcaric regosol. Soil samples were analyzed as ordinary soil samples in Croatia (pHKCl, pHH2O, organic matter, ammonium lactate (pH 3.75) extracted P and K). In addition to that, potassium was racted with ammonium acetate (pH 7) and with ammonium acetate+EDTA (pH 4.6). In the spring of 2003 the dystric luvisol was limed with 0, 10 or 20 tha-1 carbocalk. During next 4 seasons four different crops were grown without fertilization, with standard fertilization and with doubled phosphorus amounts. All three soil-K tests showed very significant correlations, fertilization impact on extractable soil-K and can be efficiently used for fertilizer recommendations. Balance calculation is closer to results of extractable potassium on fertilized plots than on control plots, and using AAEDTA or AL than AA extraction.

potassium ; soil K-tests ; fertilizer recommendations

Rad je prezentiran na skupu 10th International Symposium on Soil and Plant Analysis.