Mineralization potency of N-NH4 + and N-NO3 - at Andisol Soil planted vegetables on highly upland.

Abstract

Nitrogen is one of essential minerals for plant but it has less availability in the soil. Nitrogen is absorbed by plant as NH4 + (ammonium) and NO3 - (nitrate). Nitrogen organic in the soil is easy to change so this experiment was carried out to measure mineralization potency of N-NH4 + and N-NO3 - at Andisol Soil planted vegetables on highly upland. Andisol soils sample used came from Kejajar Wonosobo and Sumowono Semarang represent farmer 1 and 2. The first step of analysis was preparation of soil sample, and put it into PVC (diameter 5,4 cm and high 10 cm) for incubation. Experiment needed 102 days incubation with 9 times sampling with time duration of each sampling is 0, 7, 18, 31, 46, 60, 74, 88, and 102 days. Then, NH4 + and NO3 - contents of the soil were analyzed using KCl and CaCl2 spectrofotometri method. Based on the experiment, mineralization potency of released N-NH4 + at Kejajar Wonosobo from soil farmer 1 and 2 were 7,45 and 7,15 mg kg-1, whereas N-NO3 - of farmer 1 and 2 were 111,20 and 123,41 mg kg-1, respectively. Mineralization potency of released N-NH4 + at Sumowono Semarang from soil farmer 1 and 2 were 7,23 and 7,17 mg kg-1, whereas N-NO3 - of farmer 1 and 2 were 94,95 and 103, 55 mg kg-1, respectively. Ammonium or Nitrate mineralization processes almost has same pattern in andisol soils at Kejajar Wonosobo and Sumowono Semarang.