Nitrogen Mineralization in Soils Added with Different Organic Materials

시용된 유기물 종류별 토양중 질소무기화

Mineralization of organic N is an important factor in determining the appropriate rate for organic waste application to cropland. The mineralization of organic N was examined using sandy soil amended with three kind of compost (municipal solid waste+biosolid, yard trimmings, yard trimmings+biosolid), respectively. During the 12-week incubation, the mineralization of organic N was determined by analyzing the inorganic N in leachates from unamended and amended soils. Soils amended with com posts made of biosolid had higher initial $NH_4-N$ concentration than unamended soil. Soil amended with compost made of yard trimmings only had slightly lower initial inorganic N concentration than unamended soil. In the soil amended with com post made of yard trimmings+biosolid, however, nitrification rate was enhanced in the first week of incubation. Net N mineralization and nitrification were positive in all treatments. Although the greatest net N mineralization occurred in the soil amended with compost made of yard trimmings+biosolid, the greatest net mineralization and nitrification rates occurred in unamended soil.

토양에 시용되는 각종 폐유기물들의 토양중 질소 무기화율을 알아보기 위하여 3종의 폐유기물(A:도시고형폐기물+하수슬러지, B:목재잔사, C:목재잔사+하수슬러지)를 토양에 처리한 뒤 12주 동안 $25^{\circ}C$ 호기조건에서 질소 무기화율을 조사한 결과, 초기 질산화율은 C 처리구가 다른 처리구에 비하여 높았다. 또한 무기화된 총질소량은 C 처리구에서 가장 많았으나 실험기간 동안의 질소 무기화율과 질산화율은 무처리구에서 높게 나타났다.