Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China.
Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China; HongHe University, Mengzi 661100, China.
Sci Total Environ. 2023 Oct 1;893:164705. doi: 10.1016/j.scitotenv.2023.164705. Epub 2023 Jun 7.
Pteris vittata L. (PV), an arsenic (As) hyperaccumulator, has a potential to extract As from As-polluted soils. Since available As in soils can be taken up by PV, As fraction variation associated rhizosphere environmental characteristics caused by municipal sewage sludge compost (MSSC) could provide possible to strengthen As phytoextraction by PV. In this study, the mechanism of phytoextraction of PV aided by MSSC was revealed from aspect of environmental characteristics of rhizosphere soils and physiological properties of PV. The effect of MSSC on available As in soils was investigated by soil incubation experiment. Furthermore, the influences of MSSC on enzymes activities, communities of soil bacteria and fungi, As concentrations, and As fraction in rhizosphere soils of PV were explored, and then the biomass and As accumulation of PV were examined by greenhouse pot experiments. After 90 days, available As in soil incubation experiment significantly increased by 32.63 %, 43.05 %, and 36.84 % under 2 %, 5 %, and 10 % treatment, respectively, compared with control treatment. Moreover, As concentrations in rhizosphere soils of PV under 2 %, 5 %, and 10 % treatment decreased by 4.62 %, 8.68 %, and 7.47 %, respectively, compared with control treatment. The available nutrients and enzyme activities in rhizosphere soils of PVs were improved under the MSSC treatment. Affected by MSSC, the dominant phylum and genus for both bacterial and fungal communities didn't change, but their relative abundance increased. Additionally, MSSC significantly increased biomass of PV with corresponding mean ranging from 2.82 to 3.42 g in shoot and 1.82 to 1.89 g in root, respectively. And the concentrations of As in shoot and root of PV treated by MSSC increased by 29.04 %-144.7 % and 26.34 %-81.78 %, respectively, in relative to control. The results of this study provided a basis for MSSC-strengthened phytoremediation for As-polluted soils.
凤尾蕨(PV)是一种砷(As)超富集植物,具有从受 As 污染的土壤中提取 As 的潜力。由于土壤中可利用的 As 可以被 PV 吸收,因此 MSSC 引起的根际环境特征的 As 形态变化可能为通过 PV 强化 As 植物提取提供可能。在这项研究中,从根际土壤环境特性和 PV 的生理特性两个方面揭示了 MSSC 辅助 PV 植物提取的机制。通过土壤培养实验研究了 MSSC 对土壤中可利用 As 的影响。此外,还探讨了 MSSC 对土壤细菌和真菌群落、根际土壤中 As 浓度和 As 形态以及 PV 生物量和 As 积累的影响,然后通过温室盆栽实验进行了研究。90 天后,与对照处理相比,土壤培养实验中 2%、5%和 10%处理下土壤中可利用 As 分别显著增加了 32.63%、43.05%和 36.84%。此外,与对照处理相比,2%、5%和 10%处理下 PV 根际土壤中 As 浓度分别降低了 4.62%、8.68%和 7.47%。MSSC 处理改善了 PV 根际土壤中的可利用养分和酶活性。受 MSSC 影响,细菌和真菌群落的优势门和属没有改变,但它们的相对丰度增加了。此外,MSSC 显著增加了 PV 的生物量,其地上部分的平均生物量为 2.82-3.42g,地下部分的平均生物量为 1.82-1.89g。与对照相比,MSSC 处理下 PV 地上部分和地下部分的 As 浓度分别增加了 29.04%-144.7%和 26.34%-81.78%。本研究结果为 MSSC 强化受 As 污染土壤的植物修复提供了依据。