本研究嘗試以植生復育技術來萃取受電鍍廢液污染之改質坋質壤土(silty loam)中吸附於土壤上之銅、鎳及鉻。坋質壤土於加入5%、10%以及15%之堆肥改質後,分別種植油菜(Brassica napus L.)、向日葵(Helianthus annuus L.)、番茄(Lycopersicon esculeutum)以及肥皂草(Saponaria officinalis)於盆栽試驗中,以觀察其生長狀況及植體內重金屬的累積量。
研究結果顯示,油菜與番茄等植物無法於原始土壤中發芽生長,因此於此類型土質環境下須先進行土質改良方能以植生復育之方式進行土壤整治作業。重金屬均主要累積於植物的根部位置。植物於5%AS環境下的植株體內觀察到較高之金屬濃度,但是於10%AS或15%AS環境下擁有較高生質量之植株卻含有較高之金屬含量,此部分顯示出植物的高生質量與重金屬的容雀q有著顯著的關係。
油菜所累積的銅(96.8 mg/kg)、鉻(302 mg/kg)與鎳(119 mg/kg)濃度均為四種植物中之最高,而油菜中的銅(0.16 mg/株)與鉻(0.53 mg/株)含量以及番茄中的鎳(0.23 mg/株)含量為四種植物中之最高。 In this study, an attempt was made to apply phytoremediation techniques to treat silt loams contaminated by copper, chromium, and nickel disposed from a plating plant. Composts of 5%, 10%(w/w), and 15%(w/w) were mixed with the silt loams to form the amended soils. We selected four different species of plants in this study: rapeseeds (Brassica napus L.), sunflowers (Helianthus annuus L.), tomatoes (Lycopersicon esculeutum), and soapworts (Saponaria officinalis). Pot experiments were used to evaluate the plant growth and metal uptake. The results indicated that seeds of rapeseed and tomato could not germinate in original silt loams. Their soil texture must be modified so that phytoremediation can be effective. From experiments using the amended soils, it was found that the majority of metal were accumulated in the roots of the plants. The maximum metal concentration in plant bodies occurred at the 5% compost ratio, but plants had greater growth of biomass at 10% or 15% compost ratios, which resulted in a higher overall metal uptake. Thus, plants with greater growth will have higher metal tolerance.
The maximum metal concentrations of Cu (96.8 mg/kg), Cr (302 mg/kg), and Ni (119 mg/kg) in plant bodies were all found in rapeseeds. The maximum metal masses of Cu (0.16 mg/plant), and Cr (0.53 mg/plant) by plant uptake were also found in rapeseeds, while that of Ni (0.23 mg/plant) was found in tomatoes.