1. Graduate Institute of Environmental Engineering, National Taiwan Univ., No. 71, Chou-Shan Rd., Taipei 10673, Taiwan.
2. Professor, Dept. of Environmental Science and Engineering, National Pingtung Univ. of Science and Technology, Pingtung 91201, Taiwan.
3. Distinguished Professor, Graduate Institute of Environmental Engineering, National Taiwan Univ., No. 71, Chou-Shan Rd., Taipei 10673, Taiwan; Carbon Cycle Research Center, National Taiwan Univ., No. 71, Chou-Shan Rd., Taipei 10673, Taiwan (corresponding author).