Calagem em solos de varzea e a disponibilidade de nutrientes na solucao do solo apos o alagamentoLiming in lowland soils and nutrient availability in soil solution after flooding

摘要

Liming changes soil pH, reduction process and nutrient availability in flooded soils used for rice production. However, the lime requirement for rice production is variable depending on the situation. The objective of the experiment was to evaluate the nutrient release to soil solution after flooding of three lowland soils with different pH values resulting from different lime application. Soils samples from 0 to 20 cm were collected in three places and mixed with different lime quantities: zero, 1/2 SMP to pH 5,5; 1 SMP to pH 5,5; and I SMP to pH 6,0. After 90 days of incubation, the samples were placed in plastic pots with a soil solution collector After flooding, soil solution was collected at 2, 8, 15, 22, 28, 42 and 56 days and Fe, Ca, Mg, K e P concentrations were analyzed After flooding, the Fe concentration was reduced, the Ca and Mg were increased, and the K and P concentrations were not changed by lime rates. The soil solution nutrient concentrations after liming were different among the three soils types.