Seasonal changes in the CO2 fixation rate and water-use efficiency in the leaves of six evergreen and two deciduous broad-leaved tree species on Jeju Island, Korea, were measured using a portable photosynthesis analyzer, to identify which species are most efficient in taking up CO2 from the air. The CO2 fixation rate was high in the deciduous species in spring and summer and decreased in fall, whereas it was high in the evergreen species in summer and fall and decreased in winter. The rate remained high in the deciduous tree Prunus yedoensis from spring to fall (> 7.1 μmol CO2/m2/s) and in two evergreen trees, Castanopsis cuspidata var. sieboldii and Cinnamomum camphora, in summer and fall (7.0 9.9 μmol CO2/m2/s). Therefore, these tree species fix atmospheric CO2 effectively. The water-use efficiency was higher in evergreen species than in deciduous species regardless of the season. Exceptionally, it was high in the deciduous species Zelkova serrata in spring and summer (> 100 μmol CO2/mol H2O), suggesting that Z. serrata is a useful tree for dry conditions due to its tolerance of water stress. The regressions of the CO2 fixation rate versus the evaporation rate and stomatal conductance were linear and non-linear, respectively. This suggests that the stomatal activity of leaves plays an important part in CO2 fixation of plants. In conclusion, C. cuspidata var. sieboldii, C. camphora, and P. yedoensis should be planted along roads or in urban spaces for the greening of cities and mitigation of CO2 concentrations in the air.

Abstract
1. 서 론
2. 재료 및 방법
    2.1. 식물재료
    2.2. 기상환경
    2.3. CO2 흡수율과 수분이용효율의 측정
    2.4. 통계분석
3. 결과 및 고찰
    3.1. 기상 요인의 계절적 변화
    3.2. CO2 흡수율의 종간 비교
    3.3. 수분이용효율의 종간 비교
    3.4. 증산률, 기공전도도의 변화에 따른 CO2 흡수율
4. 결 론
REFERENCES

• 오순자(농촌진흥청 국립원예특작과학원 온난화대응농업연구소) | Soonja Oh (Research Institute of Climate Change and Agriculture, National Institute of Horticultural and Herbal Science)
• 김현철(제주특별자치도 한라생태숲) | Hyoun-Chol Kim (Halla Eco-forest, Jeju Special Self-Governing Province)
• 강희석(제주특별자치도 세계유산본부 한라 수목원) | Hee-Suk Kang (Halla Arboretum, World Heritage Office, Jeju Special Self-Governing Province)
• 신창훈(제주특별자치도 세계유산본부 한라 수목원) | Chang-Hoon Shin (Halla Arboretum, World Heritage Office, Jeju Special Self-Governing Province)
• 고석찬(제주대학교 생물학과) | Seok Chan Koh (Department of Biology, Jeju National University) Corresponding author