Haghnazar Hamed, Sabbagh Kourosh, Johannesson Karen H, Pourakbar Mojtaba, Aghayani Ehsan
Department of Watershed Sciences, Utah State University, UT, USA.
Department of Civil and Environmental Engineering, Amirkabir University of Technology, Tehran, Iran.
Mar Pollut Bull. 2023 Mar;188:114699. doi: 10.1016/j.marpolbul.2023.114699. Epub 2023 Feb 8.
The present study evaluated the status of sediment toxicity and pollution, and the phytoremediation capability of Typha latifolia L. (TlL) within the largest coastal wetland in the southwest of Iran, the Shadegan International Wetland. In eight sampling sites, covering the entire wetland, the concentration of six toxic elements (As, Cr, Cu, Ni, Pb, and Zn) in the surface sediment, root, and stem of TlL were measured. The results indicated that mean concentrations of Cr, Cu, Pb, and Zn were found to be higher than those in the local background, which likely indicates anthropogenic sources of these elements. Due to the presence of a nearby landfill, the results of modified pollution index (MPI) and aggregate toxicity index (ATI) indicated a moderately-heavily polluted level and moderate to high toxic degree, respectively. However, the medium-low level of toxicity toward living of organisms (21 % probability) was detected based on the assessment of the Sediment Quality Guidelines (SGQ). The results of our study indicate that the root and stem tissues of TlL are capable of acting as an indicator of Cu/Pb/Zn and Zn pollution in sediment, respectively. Considering the potential of phytoremediation, TlL represented both phytostabilization and phytoextraction capabilities for Pb and Zn and a significant increase was observed in the phytoremediation capability by increasing the distance from the landfill area. According to the results of the metal accumulation index (MAI) and comprehensive bioconcentration index (CBCI), TlL grown in the study area showed an acceptable performance in the accumulation of multiple toxic elements compared to that in Turkey, India, and Poland. Overall, TlL is a good candidate for the phytoremediation of sediments contaminated by Pb and Zn.
本研究评估了伊朗西南部最大的沿海湿地——沙德甘国际湿地的沉积物毒性和污染状况，以及宽叶香蒲（TlL）的植物修复能力。在覆盖整个湿地的八个采样点，测量了表层沉积物、TlL的根和茎中六种有毒元素（砷、铬、铜、镍、铅和锌）的浓度。结果表明，铬、铜、铅和锌的平均浓度高于当地背景值，这可能表明这些元素存在人为来源。由于附近有垃圾填埋场，改良污染指数（MPI）和综合毒性指数（ATI）的结果分别表明污染程度为中度至重度，毒性程度为中度至高。然而，根据沉积物质量指南（SGQ）的评估，检测到对生物生存的毒性处于中低水平（概率为21%）。我们的研究结果表明，TlL的根和茎组织分别能够作为沉积物中铜/铅/锌和锌污染的指标。考虑到植物修复的潜力，TlL对铅和锌具有植物稳定和植物提取能力，并且随着与垃圾填埋场距离的增加，植物修复能力显著提高。根据金属积累指数（MAI）和综合生物富集指数（CBCI）的结果，与土耳其、印度和波兰相比，研究区域内生长的TlL在多种有毒元素的积累方面表现出可接受的性能。总体而言，TlL是铅和锌污染沉积物植物修复的良好候选植物。
