INCUBATION AT COMBINATION ROCK PHOSPHATE AND KIND OF ORGANIC MATTER ITS EFFECT TO ANDIC PROPERTIES AND P AVAILABILITY ON AN ANDISOL
Andriko Noto Susanto
A pot experiment to study the effect of times incubation at incorporation of rock phosphate and kind of organic material on andic properties and P availability Andisol was conducted in the green house from December 2000 to February 2001. The experiment used completely randomized design in the two factorial experiment with three replications. The first factor was the rate of rock phosphate at four levels namely 0; 150; 300 and 450 kg P2O5.ha-1. The second factor was 16 ton.ha-1 kind of organic material consisting of: without organic matter (C0); with ordinary cow manure (C1); activated microorganism cow manure (C2) and guano (C3) addition. The incubation was conducted in 21 days and every seven days were determined: pH H2O, Al oxalate (Alo) + ½ Fe oxalate (Feo) and P availability. At the end of incubation (21 days) the soil chemical properties were analized, consisting of P retention and C organic. The result showed that at seven days incubation were decreased of Alo+½Feo and to increased of pH H2O and P available. At 14 day incubation P availability is highest and lowest of Alo+½Feo. Correlation between P availability and C organic was positive significant, even though between P availability and Alo+½Feo and P retention was negative significant.
Publised : Soil and Water Journal, Vol.3. No.2, December, 2002. Soil Science Departement, Agriculture Fakulty, UPN “Veteran” Jogjakarta - Indonesia