본 연구는 $CO_2$ 증가와 Pb 오염이 소나무 묘목에 미치는 영향에 대하여 조사하였다. 납 오염 토양(500 mg/kg-soil)과 비오염토양에 2년생 소나무를 식재한 후, $CO_2$ 농도를 380 PPM 혹은 760 ppm으로 조절한 배양기에서 3개월간 생육시킨 후, 소나무 묘목의 성장, 납 함량 변화 및 토양의 물리 화학적 변화를 조사하였다. 소나무의 생체량과 뿌리 길이는$CO_2$ 농도에 따라 유의적인 차이를 보이지 않았으나, 납에 의한 저해는 뚜렷이 나타났다. 납 오염 토양에서 토양중의 납 잔류랑은 $CO_2$ 농도에 영향을 받지 않았으나, 소나무 뿌리중의 축적량은 $CO_2$ 농도가 높으면 2배 정도 높았다. 이러한 결과는 $CO_2$ 농도 증가가 소나무 뿌리의 Pb 생물 이용성에 영향을 미치는 것을 시사한다.
This work was investigated the effects of the elevated $CO_2$ and Pb contamination on the growth of Pinus densiflora. Two-years pine trees were planted in Pb-contaminated soils (500 mg/kg-soil) and uncontaminated soils, and cultivated for 3 months in the growth chamber where $CO_2$ concentration was controlled at 380 or 760 ppmv. The growth of P. densiflora were comparatively analyzed in 4 kinds of soil samples (CA : $CO_2$ 380 ppmv + Pb 0 mg/kg, CB : $CO_2$ 380 ppmv + Pb 500 mg/kg, EA : $CO_2$ 760 PPmv + Pb 0 mg/kg, EB : $CO_2$ 760 ppmv + Pb 500 mg/kg). It was measured the growth changes of the p. densiflora caused by $CO_2$ concentration and Pb contamination. The growth of P. densiflora was remarkably inhibited in the Pb-contaminated soil, although the biomass and the root elongations were not significantly affected by the elevated $CO_2$. These results suggested that the growth of p. densiflora was sensitively influenced by Pb contamination rather than $CO_2$ concentration. Compared to the initial soil, total Pb concentration in the soil samples was decreased at 760 ppmv $CO_2$ as well as at 380 ppmv $CO_2$ after 3 months. The accumulation of Pb in the roots at 760 ppmv $CO_2$ was two-fold of that at 380 ppmv $CO_2$, indicating that Pb bioavailability in the root of p. densiflora might be affected by the elevated $CO_2$.
