The effect of liming on different organic and inorganic carbon forms in soil was studied in a pot experiment on acidic sandy soil (pH(H2O)=4.38; pH(KCl)=3.42). We used three kinds of liming doses (which were signed M1, M2, M3,). M1 was half of the M2 dose; M2 was the calculated lime dose and M3 was one and the half dose of M2. Lime (CaCO3) was
...mixed into the soil in powdery form. In addition to liming treatments, a uniform N, P and K treatment (1-1-1g N, P2O5 and K2O per pot) was given. Water supply was set up to 75% field water capacity of soil. Pots were watered daily. During the vegetation period soil and plant (oats; Avena sativa L.) samples were taken from each treatment three times (after 6-10-15 weeks). We determined inorganic- and total-C of the soil by Vario EL element analyser (based on dry combustion method) and calculated the organic-C. The conclusions can be summarized as follows: – Liming treatments had a significant positive effect on the soil-pH and caused quantitative change of different carbon forms of soil. – Increasing tendency of liming doses caused more intensive changes in inorganic- and organic-C forms of soil. – A significant correlations was found between the soil pH and the inorganic-C fraction of soil. – A decreasing correlation was found between the vegetation period and the organic-C fraction.
The effect of NPK-fertilization on the dynamics of nutrient uptake of maize (Zea mays L., cv. Clarica) was examined on chernozem soil under irrigated and non-irrigated conditions in a field experiment. The following results were made: • the element concentrations in the plant decreased over time, • there is no difference between th
...e dynamics of nutrients on irrigated and non-irrigated sites because rainfall was satisfactory for plants in vegetation period, • the N doses not only significantly increase the nitrogen content in maize, but also have a noticable effect on Ca and Mg concentrations, • because of the acidifying effect of N-fertilizers, increasing the amount of N-fertilizer increased the Mn, Zn, Cu content of the plants, • the P doses have a significant effect on the maize P and N content and the Zn concentration of the plant via P-Zn antagonism in the soil, • as the high K doses treatments alter the ion ratios in the soil, the Ca, Mg content of the plant decreased.
