Study on the Soil Improvement in the Grassland I. Effects of the dolomite particle and the shell powder application on soil characteristics, dry matter yield and nutritive value of forages in loam soil
본 시험은 양토에 조성된 혼파초지에서 석회석의 입자도 및 패각분이 토양특성, 목초의 건물수량 및 영양성분에 미치는 영향을 구명하기 위하여 축산기술연구소 초지사료과의 시험포장에서 무처리, C a ( O H ) 2 , 도로마이트 0.5, 2.0, 4.0mm 및 패각분을 각각 중화량으로 총 6처리로 하여 '94년부터 '96년까지 실시하였다. 분진발생율은 도로마이트 시용으로 크게 줄일 수 있었으며, 용해율은 패각분 시용구에서 가장 높았다. 목초의 3년 평균 건물 수량은 소석회>패각분>도로마이트 0.5mm>4.0mm>2.0mm>무처리>순이었으며 유의적인 수량차이는 없었다. 목초의 무기물 함량 중 Ca과 Mg 모두 '94년에는 처리간 차이는 없었으나 '95년에는 무처리보다 모두 증가하였으며, K와 Na은 처리간 차이가 없었다. 석회 요구량은 연차가 경과할수록 ha당 2,630kg에서 6,150kg으로 크게 증가하였으며, 토양경도는 초기에는 적정범위였으나 시용 후 시간이 경과할수록 토양이 단단해지는 경향이었다. 토양삼상은 무처리를 제외하고 처리구가 고상 함량이 낮았다. 토양유기물 함량과 유효인산 함량은 패각분 처리가 높았으며, K, Ca과 Mg 함량은 처리간 차이가 없었다. Ca 함량은 '95년에는 시험전 토양보다 약간 높았고, '96년은 약간 감소하였다. 또한 Mg 함량은 '95년과 '96년 모두 시험전에 비하여 감소하였다. 이상의 결과로서 도로마이트와 패각분은 토양개량시 석회 대체제로서 농가에서 분진 발생 및 연안오염을 해결할 수 있는 가능성을 보여 주었으며, 양토 초지에서 도로마이트나 패각분은 3년마다 시용하여 주는 것이 바람직할 것이다.
This study was conducted to investigate the effects of application of the dolomite particle and the shell powder on soil characteristics, dry matter yield and nutritive value of forages in loam soil at the experimental field of National Livestock Research Institute, Suwon, from 1994 to 1996. Application treatments were control, lime, dolomite 0.5, 2.0, 4.0mm, and shell powder in mixed pasture. Rate of dust occurrence was greatly decreased according to dolomite application and the dissolving rate in soil was highest in shell powder application among treatments. Although there was no significant difference, average dry matter yield of forages for 3 years was slightly increased with the application of lime, shell powder, dolomite 0.5mm, 4.0mm, 2.0mm and control in order. Both Ca and Mg contents of forages were no differences among treatments in 1994. However, all treatments were higher than those of control in 1995. And K and Na contents of forages were no differences among treatments. Lime requirement was greatly increased from 2,630 to 6,150kg per ha with the lapse of time. Although soil hardness was optimum level at first, it was likely to become hard little by little after treatments. Solid phase of soil was lowered a little except for control. Organic matter and available P 2 O 5 contents of soil were highest in shell powder application among treatments, and K, Ca and Mg contents of soil were no differences among treatments. Ca content was increased a little in 1995, but decreased a little in 1996 compared to that of soil before treatments in 1994. AIso, Mg content was lowered than that of soil before experiment in 1995 and 1996. The results demonstrated that use of dolomite and shell powder as lime substitutes could be reduced dust problem and coast pollution as well as soil improvement. Therefore, it is desirable to apply the dolomite and the shell powder every 3 years in loam soil.