Study on greenish landscape and phytoremediation at copperand zinc enriched covered soil in landfill

• Main Authors: Sheng-mao Wang, 王勝茂
• Other Authors: Min-Chao Wang
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/40413126576158816397

碩士 === 朝陽科技大學 === 環境工程與管理系碩士班 === 99 === When the landfill operating expires, it is necessary to conduct planning and remediation methods for reuse of land. If no proper secondary pollution prevention measure is taken to reduce the future extent of environmental pollution, it would cause other source of hazardous environmental pollution. Phytoremediation is using plants for remediation and removal of contaminated organic and inorganic compounds or metals in soil. It is an effective, inexpensive and friendly method of environment. In recent years, phytoremediation is an emerging technology of soil remediation. In Taiwan, the landfills are often buried by incinerator ashes which cause presence of high levels of heavy metals in soil. Therefore, this study investigates on removal of heavy metals in landfill sites through phytoremediation process in order to minimize environmental pollution. Two types of soils (alluvial soil and red soil) were used in the study and quartz sand as a control matrix. Test soil was added to the incinerator ashes to make final concentration of copper 100, 200, 400, 800 mg kg-1 and the concentration of zinc to reach 500, 100, 2000, 3000 mg kg-1 respectively. Ryegrass and centipedegrass were selected as phytoremediation plants for removal of metals from contaminated soils of landfills. Results showed that grown ryegrass had the highest removal percentages of Cu and Zn in quartz sand were 16%, 18%, alluvial soil were 15%, 18% and red soil were 15% and 20% respectively. Grown centipedegrass showed highest removal of Cu and Zn in quartz sand 12%, 11%, alluvial soil 12%, 12% and red soil 10% and 17% respectively. Results showed that by this process, percent removal of Zn from soils and biomass of plants (root and shoot) was high than Cu. Ryegrass had more efficiency for removal of heavy metals than centipedegrass. Total microbial population of bulk soil and rhizosphere soil, and low molecular weight organic acids had showed influence on extent of removal of metals by plants. The results showed that both the plants ryegrass and centipedegrass are suitable for removal of Cu and Zn in the soil. Though the removal efficiency is not high, this could be increased by rapid growth of grasses and in this manner continuous planning could achieve greenish landscape.