菲与芘在砂基培养的红树植物秋茄中的分布与可视化定位

Distribution and the visual positioning of phenanthrene and pyrene in sand culturing Kandelia obovata

本研究采用系列浓度盆栽试验研究多环芳烃(PAHs)菲与芘在红树植物秋茄(Kandelia obova-ta)中的迁移与分布规律,采用加速溶剂萃取(ASE)法和气相色谱-质谱(GC-MS)方法测定秋茄叶片和根中的多环芳烃含量,应用倒置荧光显微镜对秋茄叶片中的多环芳烃进行定位表征.结果表明:秋茄能从培养液中吸收菲和芘,并将根系吸收的菲和芘向叶片运输.秋茄体内菲和芘含量随处理时间(4、8、21 d)呈现先上升后下降的趋势,在培养8 d达到最大值.与4 d和8 d处理相比,在21d试验完成后,秋茄根与叶中的菲和芘含量显著降低,表明在红树植物体内存在明显的PAHs降解或者挥发.秋茄根系中的菲和芘含量随处理浓度提高而增高,与叶片相比,PAHs更多地在根部累积.在叶片中,菲和芘主要储存在叶片的维管束及附近的海绵组织中.

Used pot tests a series of concentrations of polycyclic aromatic hydrocarbons phenanthrene and pyrene,migration and distribution mechanism in mangrove Kandelia obovata were studied.Accelerated solvent extraction（ASE） and gas chromatography-mass spectrometry（GC-MS） were used to determine the PAHs concentration in leafs and roots.Visualization of polycyclic aromatic hydrocarbons in K.obovata leaves were analyzed with an inverted fluorescence microscope.The results showed that K.obovata uptook phenanthrene and pyrene from the culture medium and phenanthrene and pyrene were transported from roots to leaves.Compared with 4 days and 8 days cultivation,the trial in the 21 days showed that phenanthrene and pyrene distribution in roots and leaves were significantly decreased.It indicated that PAHs degradation,or volatilization,occurred in the mangrove plants.Compared with leaves,phenanthrene and pyrene were accumulated mostly in roots and increased with increasing culture concentration.However,phenanthrene and pyrene is mainly stored in the vascular bundles and near the spongy tissues of the leaf.