Background : The first planted field is decreasing due to replant failure and climate change. As a result, there is an increasing number of cases where new soil is covered in agricultural land or clearing forest to cultivate ginsengs. In this case, it is essential to improve the chemical properties of the soil before ginseng site management. This study was carried out to investigate growth, quality of ginseng and soil chemical properties to set the concentrations of nitrogen. Methods and Results : 0, 1, 4, 8, 16, 32 ㎏/10 a of urea were each treated at 3.3 ㎡ of the field and ginseng cultivar 'Gumpoong' was transplanted. Growth characteristics were investigated by growth period and soil chemical properties were investigated every 3 months. In 2-years-old ginseng, the root weight was the highest at 4 ㎏ treatment group of nitrogen while it showed the rate of increase in root weight is increased at 1 ㎏ treatment of nitrogen in 3-years-old ginseng. Physiological disorder and root rot symptom are increased at 8 ㎏ treatment group of nitrogen in 2- and 3-years-old ginseng. In case of soil properties, EC and Nitrate-N concentration exceeded 0.5 dS/m and 50 ㎎/㎏ respectively from 16 ㎏ treatment group of nitrogen after 14 months. The saponin content tended to decrease with increasing nitrogen treatment concentration at the 2-years-old ginseng. In the case of 3-years-old, the highest value was 0.88% at 1 ㎏ nitrogen treatment group. Conclusion : These results indicate that the application levels of nitrogen influence growth, quality of ginseng and soil chemical properties. These data can be used to set the concentrations of nitrogen when new soil is covered in agricultural land or clearing forest to cultivate ginseng.

제주도 안디졸(Andisol) 토양 분포지역 중 화산성 쇄설물과 현무암으로부터 기원된 두 토양의 Bo층을 대상으로 완충능력을 계산하고 토양의 알루미늄 용해도가 완충능력에 미치는 영향을 연구하였다. 주상실험 결과는 pH 6.0과 4.0 부근에서 완충작용이 일어남을 보여 주며, 현무암기원의 토양보다 화산쇄설암기원 토양의 완충능력이 더 큰 것으로 나타났다. 다양한 pH조건에서의 배치평형실험 결과 다량의 알루미늄 함유 광물상을 갖는 제주도 안디졸 토양 Bo층에서의 알루미늄 거동은 Al(OH)3, 이모골라이트 혹은 프로토-이모골라이트 등의 고상에 주로 영향을 받는 것으로 나타났다. Bo층 토양의 광물조성, 배치 평형실험결과, 그리고 주상실험 결과를 종합해 볼 때, pH 4.0 부근에서 나타나는 뚜렷한 완충능력(β)은 깁사이트 및 프로토-이모골라이트의 용해도 특성에 의해서 좌우되는 것으로 해석된다. pH 6.0 내외의 완충작용은 규산염광물의 용해도 및 염기성양이온의 양이온교환반응에 의해 진행되고 있으나, 낮은 염기성 포화도는 토양산성화가 더 진행될 경우 이러한 완충효과가 오래 지속되지 못할 것임을 지시한다.