垃圾掩埋場高銅鋅覆土結合植生綠化與復育之研究

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

王勝茂(Sheng-mao Wang)

指導教授 ： 王敏昭 ； 張簡水紋

朝陽科技大學/理工學院/環境工程與管理系/碩士(2011年)

摘要

當掩埋場營運年限屆滿後，應對封閉之掩埋場進行復育及規劃土地再利用，在掩埋場停止使用後，若未能妥善做好二次公害防治工作，來降低周遭環境的污染程度，將成為另一個公害污染源。植生復育(phytoremediation)就是就地利用植物對受有機和無機污染之土壤進行復育，是一種有效、價格低廉且對環境友善之方法，為近年來廣受重視之整治技術，台灣現今掩埋場常因掩埋焚化爐底渣而導致土壤重金屬含量偏高，因此，本研究使用二種不同土類之掩埋土(沖積土、紅壤)並以石英砂為對照基質，試驗土壤將添加焚化爐底渣使Cu濃度達到100、200、400及800 mg kg-1，而Zn濃度為500、1000、2000及3000 mg kg-1，再利用黑麥草及假儉草復育受重金屬污染掩埋土之植生。試驗結果顯示種植黑麥草在四種濃度處理下，石英砂Cu、Zn最高去除率分別為16%、18%，而沖積土分別為15%、18%，另外紅壤分別為15%、20%，種植假儉草在石英砂Cu、Zn最高去除率分別為12%、11%，而沖積土分別為12%、12%，紅壤別為10%、17%。土壤去除率及植體中(地上部與地下部)重金屬含量，以Zn＞Cu，且黑麥草去除效果亦較假儉草佳；土壤總菌落數及根圈土壤低分子量有機酸均會影響植物對Cu與Zn去除效果；結果顯示種植黑麥草及假儉草皆能去除土壤中Cu與Zn，雖然去除效果並不高，但可藉由草類快速生長之優勢，以連續栽種方式達到植生綠化之目的。

關鍵字

垃圾掩埋場 ； 植生復育 ； 銅 ； 假儉草 ； 黑麥草 ； 鋅

並列摘要

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.

並列關鍵字

centipedegrass ； ryegrass ； zinc ； copper ； phytoremediation ； Landfill

參考文獻

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