A Study on PCP Adsorption in Various Paddy Soils of the Choongbook Area

충북지방(忠北地方) 답토양(沓土壤)에 대(對)한 PCP 흡착에 관한 연구(硏究)

Not only in order to determine reasonable application amounts of PCP in terms of soil texture, but also to get basic data for fish-toxicity-free treatment by estimating fish toxicity, some aspects of PCP adsorption were observed taking various paddy soils with different physico-chemical characteristics in the Choongbook Area as samples. The results obtained are summarized as follows: 1. There was a positive correlation between PCP adsorption and clay contents, total nitrogen, organic matter, cation exchange capacity, exchangeable bases, and phosphorus absorption coefficients, respectively; whereas there was a negative one between PCP adsorption and pH. Although they were not significant, it was remarkable that there was a relatively large amount of correlation between PCP adsorption and clay contents, $H^+,\;Mg^{++}$, and CEC, respectively. 2. PCP adsorption in terms of soil texture was in the order of Clay>Loam>Sandy loam. 3. Although PCP adsorption in the $H_2O_2-treated$ soils decreased remarkably, it was not proportional to the humus contents. 4. The order of PCP adsorption in the exchangeable base-treated soils was H^+-exchanged soil>$K^+-soil$>$Na^+-soil$>$Ca^{++}-soil$>Mg^{++}-soil. 5. Langmuir's and Freundlich's adsorption isotherms were applicable to the PCP adsorption, and thereby were able to be calculated maximum adsortion amounts of PCP, bond energy, and the depths of adsorption layers. 6. Maximum adsorbed amounts of PCP were 212.14 mg/100gr in Clayey loam, 97.28 to 121.59mg/100gr in Loam, and 32.92 to 91.74mg/100gr in Sandy loam, respectively. 7. The depths of mixed layers of limiting application for fish-toxicity-free treatment were 0.88cm of the Jinchun soil, the shallowest and 4.29 cm of the Naesan-ri Sandy loam, the deepest.

토성에 따라 합리적인 PCP시용량을 결정하고 아울러 어독해의 추정으로 무어독 처리방법을 강구하기위한 기초자료를 얻고자 물리 화학적 성질을 달리하는 수종의 충북지방 답토양을 시료로 하여 PCP의 흡착관계를 살펴본바 그 결과는 다음과 같다 1. 토양의 점토함량, 전질소, 유기물, CEC, 치환성염기, 인산흡수계수등과 PCP 흡착과의 사이에는 正의 상관이, pH와는 부(負)의 상관을 보여 주었으나 모두 유의성은 인정되지 않았다. 그러나 점토함량, $H^+$, Mg 및 CEC와 PCP흡착과는 비교적 큰값을 보여주어 주목할만한 일이었다. 2. 토성별로 PCP흡착은 식토>양로>사질양토의 순이었다. 3. $H_2O_2$처리 토양에서의 PCP흡착은 현저하게 저하하지만 그 줄어든 비율은 부식의 함량에 비례하지는 않았다. 4. 치환성 염기처리토양에서의 PCP흡착은 $H^+$-토양>$K^+$-토양>$Na^+$-토양> $Ca^{++}$-토양>$Mg^{++}$-토양의 순이었다. 5. PCP의 흡착관계를 Langmuir's adsorption isotherm과 Freundlicr's adsorption isotherm으로 표현가능하며 이로서 PCP의 최대 흡착량과 결합 energy 및 흡착층(吸着層)의 길이를 산출할수 있었다. 6. 토성별로 PCP 최대흡착량을 보면 식양토는 213.13mg/100gr, 양토는 $97.28{\sim}121.59mg/100gr$, 사양토는 $32.93{\sim}91.74mg/100gr$ 이 었다. 7. 무어독처리를 위한 한계시용량의 혼합토층의 깊이는 진천토양이 0.88cm로 가장 얕은 그리고 내산리 사질양토는 4.29cm로 가장 깊은 혼합시용을 요한다.