논토양검정에 의한 토성별 돈분퇴비 적정 시용량 결정

Effects of Composted Pig Manure on Rice Cultivation in Paddy Soils of Different Texture

토양비옥도와 토성이 서로 다른 논토양에서 수도 생산성과 환경을 고려한 가축분퇴비의 적정시용기준량을 확립하기 위하여 남계 사양토, 용지 양토, 화동 식양토에서 돈분퇴비를 0, 5, 10, 20 톤 $ha^{-1}$을 시용하고 추청벼를 공시 품종으로 하여 포장시험을 1년간 수행하여 다음과 같은 결과를 얻었다. 토양검정에 의한 화학비료 시용시 돈분퇴비 적정시용량은 사양토 4.0, 양토와 식양토 7.0 톤 $ha^{-1}$ 이었으며, 이때의 정조 수량은 사양토 7.440, 양토 7.000 식양토 6.020 톤 $ha^{-1}$이었다. 사양토와 양토에서 NPK와 함께 돈분퇴비를 15 톤 $ha^{-1}$ 이상 시용시에는 도복에 의한 수량 감소가 발생되었다. 수확기 식물체의 양분흡수량은 돈분 퇴비 시용량이 증가할수록 많아지는 경향이었으며, 시험 후 토양의 인산과 칼리의 함량은 돈분퇴비 시용량의 증가에 따라 높아지는 경향을 보였으며, 그 외의 성분은 처리구간 큰 차이가 없었다.

A manure compost has been identified as an alternative to fertilizer to increase soil fertility and crop production in farming fields. The aim of the present study was to evaluate the effects of pig manure compost on soil properties and rice productivity as well as to determine the optimum application rate. In 1997, a field experiment was carried out to evaluate the growth of rice on sandy loam, loam, and clay loam soils amended with 0, 5, 10, and $20Mg\;ha^{-1}$ of pig manure compost plus NPK, which decided by soil testing. Rice yields were higher in soils receiving manure compost amendment. The maxim um yields were evaluated with $7,520kg\;ha^{-1}$ in the levels of $4.2Mg\;ha^{-1}$ of pig manure compost application plus NPK in sandy loam, $7,320kg\;ha^{-1}$ in the levels of $10.7Mg\;ha^{-1}$ in loam, and $6,320kg\;ha^{-1}$ in $17.2Mg\;ha^{-1}$ in clay loam soil. The optimum application rate of pig manure compost, which decided for 95% of maximum yields, was $4.0Mg\;ha^{-1}$ in sandy loam and $7.0Mg\;ha^{-1}$ in loam and clay loam soils under the condition of chemical fertilization by soil diagnosis. An increase in rice yield indicated a better nutrient status in compost-amended soil which was supported by the higher nutrient contents of N, P and K in shoot of plants grown in soil with manure compost amendment. Addition of manure compost increased available phosphate, silicate and exchangeable K in the amended soils according to the rate of compost application rate. It can be concluded that the manure compost could be a suitable organic fertilizer for improving rice productivity and soil fertility, and an application rate of $4.0Mg\;ha^{-1}$ in sandy loam and $7.0Mg\;ha^{-1}$ in loam and clay loam soils would give the optimum rice yields in the standard fertilization by chemical fertilization.