Effects of Long-Term Fertilization on Light and Heavy Fractions of Soil Organic Matter in Single Cropping Paddy Soils in Korea

Advanced understanding of SOC still requires further studies on diverse soils including a wide spectrum of paddy soils and agricultural practices. The objectives of this study were to investigate the effects of long-term fertilization on both light fraction (LF) and heavy fraction (HF) of soil organic matter and the relationships among total C, C/N ratio, clay content, and fertilization type in paddy soils. Compost application led to a significant increase in HF and consequently in C and N contents. Compost plots had a higher C/N ratio compared to those of treatments without compost in HF as well as LF. Correlation of C/N ratio to LF and HF was clearly separated into two groups as a boundary of about 9.5 of C/N ratio. These results clearly show that balanced fertilization together with composting could lead to synergic effects on enhancing C sequestration as well as plant nutrition in plow layer of paddy soils in Korea. KCI Citation Count: 1