Fertilization Efficiency of Livestock Manure Composts as Compared to Chemical Fertilizers for Paddy Rice Cultivation

To promote the practical use of livestock manure compost (LC) for paddy rice cultivation, the fertilization efficiency of nutrients in LCs was investigated compared to that of chemical fertilizer. This experiment was conducted at rice field in Hwaseong, Korea, with 6 treatments by each of 3 kinds of tested LCs, cattle manure compost (CaC), swine manure compost (SwC) and chicken manure compost (ChC). The treatments consisted of 3 application levels of LCs and 3 chemical fertilizer treatments having the same application levels with LCs. <TEX>NH₄</TEX>-N content in soil became higher according to the increase in the urea application rate, while it became lower in LC plots than in urea plots, and statistically had no significant difference among LC plots. There was a close relationship between phosphate fertilization rate and the increment of soil available phosphate content after experiment resulting y = 0.1788x - 6.169 (<TEX>R²=0.9425</TEX>) when applied fused superphosphate fertilizer, and y = 0.0662x - 2.689 (<TEX>R²=0.9315</TEX>) when applied LC at the equivalent rates to phosphate input (x: phosphate application rate, kg <TEX>ha⁻¹</TEX>, y: increment in soil available phosphate content, mg <TEX>kg⁻¹</TEX>). And from these two equations, the correlation on the phosphate application rate between fused superphosphate fertilizer and LC could be obtained as y = 2.7056x - 52.492 (x: <TEX>P₂O₅</TEX> application rate of fused superphosphate, kg <TEX>ha⁻¹</TEX>, y: <TEX>P₂O₅</TEX> application rate of LC, kg <TEX>ha⁻¹</TEX>). Plant height, number of tillers, nutrients uptake by rice, and rice yield showed higher levels in N 100% and N 150% application plots of chemical fertilizers, while every LC plots exhibited lower values and no significant difference among them. Relative nitrogen fertilization efficiencies of LCs compared to urea was 12.3% for CaC, 8.8 for SwC and 24.6 for ChC, respectively.