- Daisuke Ogawa C-Date Company, Ltd
At large intersections, vehicles consume and generate a large amount of fossil fuel. Carbon derived from fossil fuels that do not contain radioactive carbon (14C), i.e., dead carbon, is released in large amounts in the roadside air environment. By means of photosynthesis, street trees along the roadside assimilate both dead carbon, not containing radioactive carbon (14C), and contemporary carbon, which includes radioactive carbon (14C). Therefore, the concentration of radioactive carbon (14C) in leaves of trees growing in heavily polluted environments decreases.