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Because the photosynthesis ability of old artificial forest stands is inferior to that of young stands, the utilization of these logs is benefit to the sequestration of carbon dioxide. Hence, construction of wooden patios, trails, and retaining wall to substitute concrete ones could reduce the carbon dioxide emission in Taiwan. According the research data, the energy consumption during wood processing was very low, so did the carbon dioxide emission. Because concrete was replaced and about 50% of wood consists of carbon which is from carbon dioxide sequestration, both the utilization of wood and artificial forest planted could reduce the carbon dioxide concentration. The purpose of the study was to evaluate the effects of carbon dioxide emission and sequestration by using wooden structure in both wooden leisure and eco-technological facilities. Results shown when check dam constructed by ACQ treated Japanese cedar following O&D (outdoor) method and CNS3000 K4 criterion with 40 years lifetime could reduce about 30 tons of carbon dioxide emission, which is equivalent to the carbon dioxide expiration of 92 persons per year. On another case, 61 tons of carbon dioxide emission was reduced, which is equivalent to the carbon dioxide expiration of 190 persons per year. If the high energy consumption materials, such as steel and cement, could be substituted by wood or wooden material, it could be beneficial to the sustainable management of the earth environment.

Six wood species were carbonized under various carbonization temperatures and nonoxygen conditions to obtained charcoal. The effects of wood species, rate of temperature rise, and carbonization temperature on the electromagnetic shielding efficiency (ESE) of the electric field were investigated. The wood species used in this study were Japanese cedar, China fir, western hemlock, red oak, fortune paulownia, and Taiwan acacia. Tested materials were carbonized in a high-temperature oven under the following conditions: rate of temperature rise 1°–5°C/min; carbonization temperature 500°–1100°C, with temperature intervals of 100°C; maximum temperature maintained for 1 h; and flow rate of nitrogen 300 ml/min. The electromagnetic insulation strength system was used to detect the ESE of the electric field of charcoal. It was found that western hemlock and fortune paulownia charcoal showed maximum ESE values of of 36 and 61 dB generated at a carbonization temperature of 1000°C. The charcoals derived from four other wood species showed maximum ESE values of 28 dB for Japanese cedar, 23 dB for China fir, 32 dB for red oak, and 38 dB for Taiwan acacia, respectively, at a carbonization temperature of 1100°C. The ESE value for fortune paulownia charcoal was similar to those of metal nets. The relations between ESE and logarithmic values of resistivity (log ρ) could be represented by a negatively exponential formula.