Langmuir phosphorus adsorption maximum as a criterion for determination of rate of phosphorus application

인산시용량(燐酸施用量) 결정기준(決定基準)으로서의 최대인산흡착량(最大燐酸吸着量)

A pot experiment was conducted to find out suitable method in determining the rate of phosphorus application. Soybean was planted under optimum moisture condition. The soils used in this experiment were cultivated and non-cultivated mineral soils, and volcanic ash soils. The results were summarized as follows: 1. Phosphorus adsorption maximum(PAM) was the good parameters to determine phosphorus adsorption capacity of all tested soils. 2. Phosporus adsorption maximum was increased with the content of ammonium acetate extractable aluminum, and the organic matter effects on PAM was considerably high in volcanic ash soils. 3. Requirement of phosphorus for maximum yields were in the range of 30~35% of PAM for tested soils. 4. PAM was considered as a suitable criteria to determine the rate of the phosphorus application and it was also considered to be more attractive than phosphorus absorption coefficient.

최선(最善)의 인산시용량(燐酸施用量) 결정기준(決定基準)을 찾고저 기경지(旣耕地), 미개간지(未開墾地) 및 제주(濟州) 화산회토양(火山灰土壤)을 공시(供試)하여 충분(充分)한 관수조건하(灌水條件下)에서 콩을 재배(裁培)한 pot시험결과(t試驗結果)를 요약(要約)하면 다음과 같다. 1. 토양별(土壤別) 인산흡착력(燐酸吸着力)의 차이(差異)를 가장 잘 나타내는 지표(指標)는 Langmuir 최대인산흡착량(最大燐酸吸着量)이었다. 2. 최대인산흡착량(最大燐酸吸着量)는 초산(酢酸)암모니움 침출(浸出) Al 함량(含量)에 비례하나 제주도(濟州道) 토양(土壤)에서는 Al외(外)에 유기물함량(有機物含量)의 영향(影響)이 컸다. 3. 최대수량(最大收量)을 얻기 위한 인산시용량(燐酸施用量)은 인산최대흡착량(燐酸最大吸着量)의 30~50% 범위에 있었다.