- 期刊
水耕蕹菜重金屬吸收性的探討
Absorption of Various Heavy Metals by Hydroponic Water Spinach
摘要
工業廢水對農作物所造成的污染影響日益嚴重，對人們的身體健康逐漸構成潛在威脅。蕹菜為本省的大宗蔬菜來源，主要採用淺水栽培，因此甚易受廢水污染。本研究以蕹菜的水耕栽培作為模式，利用含有不同重金屬(Cd、As、Pb、Hg)濃度之培養液來進行栽培，探討蕹菜對不同重金屬吸收的差異性。水耕培養液中分別加入含有10^(-4)與10^(-6) M濃度的各個重金屬元素，種植15天後分析蕹菜樣品根、莖、葉各部位中重金屬的含量。結果發現蕹菜根部的重金屬元素含量均較莖、葉為多，其在根部之含量多寡依序為Hg、Cd、Pb、As，而在莖部和葉部之含量多寡順序，則均為Hg、As、Pb、CD，同時葉部的相對含水率，卻會隨著根部重金屬含量的增加而呈現有減少的情形。此乃因累積於蕹菜根部的高量重金屬元素可能會形成重金屬壓力(heavy metal stress)。干擾蕹菜自根部至莖、葉的水份與養份傳送機制，使得莖、葉中的重金屬含量與葉片中的相對含水率減少。
並列摘要
The pollution of industrial wastewater to agricultural crops becomes more and more serious, and gradually results in a potential threat to human health. Water spinach is an important major vegetable in Taiwan. Because the cultivation is always in shallow water ponds, it is liable to the pollution of wastewater. In this research, effects of various concentrations of Cd, As, Pb, Hg on the heavy metal absorption of water spinach were studied. Each element was prepared at concentrations of 10^(-4) and 10^(-6) M in hydroponic culture solution, and water spinach was hydroponics-cultured for 15 days and element contents of roots, stems, leaves were analyzed. Results showed that roots accumulated elements more abundant than stems and leaves, and the contents were in a descending order of Hg, Cd, Pb, As. On the other hand, the contents in stems and leaves was at the same order of Hg, As, Pb, Cd. The relative water content in leaves decreased with the increase of the heavy metal contents in roots. The effect of heavy metal stress occurred in roots might disturb the transport system of water and nutrients in water spinach, and decrease the accumulation of elements and the water content in stems and leaves.