台灣地區蛇紋岩為關山火成雜岩及利吉混同層經變質作用產生,經風化後所形成的土壤中鉻與鎳含量偏高,可能造成作物、環境及地下水體潛在性的為害及污染。本論文採取台灣東部2種蛇紋岩土壤樣品,分別來自萬榮及池上,進行盆栽試驗設計不同施肥量處理,種植梗稻(台梗11號)及秈稻,施肥方式包含完全不施肥(未施用任何肥料,即空白)、120-60-60 kg/ha(意即每盆土施用化學肥料硫酸銨1.47 g,磷酸氫鈣0.17 g,氯化鉀0.14 g)、120-90-60 kg/ha(意即每盆土施用化學肥料硫酸銨1.47 g,磷酸氫鈣0.26 g,氯化鉀0.14 g)及120-120-60 kg/ha(意即每盆土施用化學肥料硫酸銨1.47 g,磷酸氫鈣0.35 g,氯化鉀0.14 g)等4種方式。探討不同施肥處理之可溶性重金屬濃度,以了解水稻不同部位重金屬(鐵、錳、鉻、鎳與鈷)之吸收量。實驗結果顯示,在不同肥料處理下,萬榮和池上土壤受到添加肥料的影響,其pH值逐漸下降。另外,不同施肥條件下以池上土壤溶液中鐵和錳濃度較萬榮高;對鉻而言,則無明顯變化。對水稻根鐵膜而言,在不同施肥處理下鐵、錳、鉻、鎳及鈷等重金屬的累積濃度大小順序為:鐵>錳>鎳>鈷>鉻。鐵、鉻、鎳與鈷等重金屬大部分累積於水稻根部,唯錳累積於莖葉部位(757.5 mg/kg)明顯較根部(400.5 mg/kg)高,水稻中的重金屬濃度較一般植物高,穀粒中鉻累積達1.16 mg/kg,鎳累積量為8.57 mg/kg。
Serpentinitic soils are high in Cr and Ni which may have the potential risk to crop growth and eco-environment, and groundwater contamination. This study used 2 serpentinitic soil samples (WR and TA) from eastern Taiwan to cultivate paddy rice by pot experiment amended with different fertilizer treatments in the open field. All treatments included control (blank), 120-60-60 kg/ha (NH4)2SO4 1.47 g, CaHPO4 0.17 g, and KCl 0.14 g per pot), 120-90-60 kg/ha ((NH4)2SO4 1.47 g, CaHPO4 0.26 g, KCl 0.14 g per pot), and 120-120-60 kg/ha ((NH4)2SO4 1.47 g, CaHPO4 0.35 g, KCl 0.14 g per pot). The experimental results indicated that WR and TA soils pH gradually decreased during rice growth, due to acidity of the chemical fertilizer addition. Addititonally, no difference was found in Cr heavy metal level in the soil solution. Fe and Mn concentrations were higher in the TA soil than in the WR soil. Iron plaque on rice roots, in the different fertilizer treatments the order of Fe, Mn, Cr, Ni and Co accumulated concentration was: Fe> Mn> Ni> Co> Cr. The results show that Fe, Cr, Ni, Co were concentrated in the root of rice, and Mn concentrations (757.5 mg/kg) in the stalk part was higher than in the root. The concentrations of all metals in the rice tissues were higher than those in general plants, and thus the Cr and Ni concentrations in the rice were up to 1.16 mg/kg and 8.57 mg/kg.