Nitrogen mineralization in soil amended with mesocarp fiber of oil palm and other wastes : A greenhouse study

Abstract

Mesocarp fiber of oil palm, sludge cake from frozen seafood factory, rick husk and organic fertilizer were mixed with a soil and incubated for 0, 15, 30, 45, 60, 75 and 90 days in plastic pots. At the end of each incubation period, NH+ 4-N and NO- 3-N contents were determined by MgO-Devada alloy steam distillation method. N-mineralization differed depending upon incubation period and types of organic amendment. At 60 days of incubation, N-mineralization of the amended soil had increased slightly. NO- 3-N content was higher than NH+ 4-N content at all incubation periods especially in the soil amended with of the mesocarp fiber of oil palm. The soil inoculated with Sclerotium rolfsii had higher rates of N-mineralization than the soil without S. rolfsii with the exception of the soil amended with mesocarp fiber of oil palm at 5 g/kg. soil and rick husk during 60-90 days of incubation period. NO- 3-N, was the dominant product of N-mineralization in soil both added with S. rolfsii and without S. rolfsii .

Keywords

• agricultural waste
• mesocarp fiber of oil palm
• N-mineralization
• Sclerotium rolfsii