Ying-Hsuan Sun

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1. Introduction Trees are the answers to conquer the environmental challenges, such as climate warming, shortage of energy and resources, reduction of tropical rain forests, desertification of land, and endangered species of wild animals and plants. In addition to fixing carbon to slow down CO2 content in the atmosphere, trees provide wildlife habitat, and conserve water. It was the raw materials for the paper industry, interior decoration, furniture, and even for pharmaceuticals.