Effects of Insecticides on Enzyme Activities in Soil Environment

살충제(殺蟲劑)가 토양환경중(土壤環境中) 효소활성(酵素活性)에 미치는 영향(影響)

The effects of insecticides on biochemical precesses in soil were studied by determining the effects of the chemical structure of each insecticides on enzyme activities, pesticide residue and total number of bacteria revealed when soil treated with urea was incubated at $28{\pm}1^{\circ}$ for 56 days. The inhibition effects of insectides on enzyme activites in soil decreased in the order: dithiophosphoric acid > thiophosphhoric acid > phosphoric acid > carbamate insecticides for urease and phosphatase, thiophosphoric acid > dithiophosphoric acid > phosphoric acid > carbamate insecticides for L-glutaminase and protease. The inhibition effects of organophophorus insecticides on enzyme activities in soil were maintained longer than those of carbamate insecticides. Carbamate insecticides increased the activities of protease and L-glutaminase at 56 days. When insecticides were treated in soil together with urea, the degradation of insecticides was accelerated. By treatment of insecticides, the total number of bacteria was decreased at the early stage of treatment but thereafter increased according to phosphoric acid and carbamate insecticides.

유기인계(有機燐系) 및 carbamate계(系) 살충제(殺蟲劑)의 처리(處理)로 뇨소(尿素)가 시용(施用)된 토양내(土壞內)의 효소활성(酵素活性) 및 잔류량(殘留量)의 변화(變化), 총세균수(總細菌數)에 미치는 영향(影響)을 규명(糾明)한 결과(結果)는 다음과 같았다. 살충제(殺蟲劑)가 urease와 phosphatase의 활성(活性)에는 dithioposphoric acid, thiophosphoric acid, phosphoric acid, carbamate계(系)의 순(順)으로 저해율(沮害率)이 높았으며, L-glutaminase와 protease의 활성(活性)에는 thiophosphoric acid, dithiophosphoric acid, phosphoric acid, carbamate계(系)의 순(順)으로 저해율(沮害率)이 높았다. 대체적으로 유기인계(有機燐系) 살충제(殺蟲劑)는 처리(處理) 후(後) 56일(日)째까지 약하게나마 저해현상(沮害現象)을 나타낸 반면 carbamate계(系)는 28일(日)째 이후에는 영향(影響)이 거의 없었다. Carbamate계(系) 살충제(殺蟲劑)는 protease와 L-glutaminase의 활성(活性)을 56일(日)째에 약간 증가(增加)시켰다. 뇨소(尿素)의 시용(旅用)으로 인(因)해 살충제(殺蟲劑)의 분해(分解)는 무시용구(無施用區)에 비해서 약간 촉진(促進)되었다. 토양내(土壞內)의 총세균수(總細菌數)는 살충제(殺蟲劑)의 처리(處理)로 초기(初期)에는 대조구(對照區)보다 감소(減少)되었으나 후기(後期)에는 phosphoric acid형(形)과 carbamater계(系)에서는 균수(菌數)가 약간 증가(增加)되었으나 thiophoric, dithiophosphosphoric acid형(形)에서는 계속 저해(沮害)를 받는 것으로 나타났다.