Determination of Application Rate of Composted Pig Manure for Wetland Rice

논토양에서 돈분톱밥퇴비 시용량 결정에 관한 연구

A study was conducted for the determination of application rate of pig-dung composted with sawdust (referred as pig manure hereafter) for wetland rice. The study involved the field experiments with the cultivation of rice under different rates of application of pig manure in combination of different rates of chemical fertilizers, in a wetland rice soil. The field experiment involved following treatments : (I) Without fertilizer, (II) Standard rate of chemical fertilizers based on soil testing($98-73-71kg\;ha^{-1}$ as $N-P_2O_5-K_2O$), (III) $2.1Mg\;ha^{-1}$ of pig manure $>+80-37kg\;ha^{-1}$ of $N- K_2O$ as chemical fertilizer(Less $N-P_2O_5-K_2O$ contained in the compost), (IV) $4.2Mg\;ha^{-1}$ of pig manure+ $62-3kg\;ha^{-1}$ of $N-K_2O$as chemical fertilizer(Less $N-P_2O_5-K_2O$ contained in the compost), (V) $10Mg\;ha^{-1}$ of pig manure+ Treatment(II), (VI) $20Mg\;ha^{-1}$ of pig manure +Treatment(II). Number of tillers in treatment (I) were higher than other treatments in tillering and panicle formation stage. After heading stage, treatments (V) and (VI) have higher number of tillers, but treatment (III) and (IV) have fewer number of tillers during all growing stage. Uptake of NPK in rice plants was higher in treatment (VI), but the efficiency of N, P and K was higher in treatment (I), (III) and (IV). The yield of unhulled rice were in order of tretments (VI)>(V)>(IV)>(II)>(III), although the difference was not statistically significant. Inorganic nitrogen, available P and exchangable K contents in soil were highest at tillering stage in all treatments and became low from panicle formation to harvest stage. Available P in soil was increased by the application of pig manure upto 20 cm depth. Exchangeable cation contents in 40 to 60 cm soil depth was much higher in treatment (VI) than in other treatments. Treatment (V) and (VI) showed much higher losses of N. $P_2O_5 $ and $K_2O$ than other treatment. Though treatment (VI) tended yield higher than in other treatments, showed lodging and occurrence of leaf and neck blast in this treatment. Yield of unhulled rice in treatment (IV) was not significant statistically and reduced nutritional losses. It is conclude that treatment (IV) seems to be the most reasonable one for the application of pig manure in combination of chemical fertilizers.

가축분퇴비와 화학비료 혼용시 시비량 결정의 기초자료를 얻기 위하여 토양검정에 의한 NPK구를 대조구로 하였고, 돈분톱밥퇴비중 인산함량을 감안하여 시용한 돈분톱밥퇴비+NK 2수준 돈분톰밥퇴비와 토양검정에 의한 화학비료 시비량을 시용한 돈분톱밥퇴비10톤 및 20톤+NPK와 무비구를 포함한 6처리로 하여 사양토에서 포장시험을 수행한 결과는 다음과 같다. 벼 생육시기별 경수는 NPK구가 분얼기와 유수형성기에서 많았으나, 출수기에는 돈분10톤 및 20톤+NPK구에서 많았으며, 돈분2.1톤 및 4.2톤+NK구에서는 전 생육기간 동안 적은 경향이었으며, 식물체의질소, 인산 및 칼리흡수량은 돈분20톤+NPK구에서 많았고, 질소이용율은 NPK구, 인산 및 칼리이용율은 각각 돈분2.1톤+NK구, 돈분4.2톤+NK구에서 높았고, 정조수량은 돈분20톤+NPK>돈분10톤+NPK>돈분4.2톤+NK>NPK>돈분2.1톤+NK구 순이었으나, 돈분4.2톤+NK구와 돈분10톤 및 20톤+NPK구의 수량은 유의차가 없었다. 생육시기별 토양중 암모니아태질소, 유효인산 및 치환성칼륨 함량은 각 처리 모두 분얼초기에 가장 높았고, 유수형성기에서 수확기까지는 낮은 상태로 유지되었으며, 분얼초기 토양의 각 성분합량은 돈분20톤 +NPK구에서 가장 많았으며, 토심별 유효인산함량의 분포는 돈분톰밥퇴비 시용량이 증가할수록0~20cm에서 많았으나 치환성양이온함량은 40~60cm에서 돈분10톤 및20톤+NPK구가 맡았다. 질소, 인산, 칼리의 손실량은 NPK구, 돈분2.1톤 및 돈분4.2톤+NK구에서 적었으나, 돈분10톤 및 20톤+NPK구에서 매우 많았으며, 투입량이 탈취량보다 적은 처리는 인산의 경우 돈분2.1톤+NK, 칼리는 NPK, 돈분4.2톤+NK구이었다. 돈분10톤 및 20톤+NPK처리시 투입량 과다로 인한 양분의 손실량이 매우 많았으며, 돈분20톤+NPK처리시 정조수량은 다소 높았지만도복과 도열병이 발생하였고. 돈분4.2톤+NK폭리시양분의 손실량이 적으면서 수량은 대조구와 비슷한 결과를 볼 때, 돈분톱밥퇴비를 $4.2Mg\;ha^{-1}$ 시용하고 퇴비중 양분함량을 고려하여 화학비료로서 조절시용 할 경우 수량 환경 경제성면에서 적절할 것으로 판단된다.