Plant Ecology Laboratory, Department of Botany, North Lakhimpur College (Autonomous), Khelmati, 787031, Lakhimpur, Assam, India.
Environ Sci Pollut Res Int. 2024 May;31(22):31843-31861. doi: 10.1007/s11356-024-33376-w. Epub 2024 Apr 19.
The aim of this study was to evaluate the efficiency of Costus speciosus (Koen ex. Retz.) Sm. in the degradation of crude oil and reduction of mercury (Hg) from the contaminated soil in pot experiments in the net house for 180 days. C. speciosus was transplanted in soil containing 19150 mg kg crude oil and 3.2 mg kg Hg. The study includes the evaluation of plant biomass, height, root length, total petroleum hydrocarbon (TPH) degradation, and Hg reduction in soil, TPH, and Hg accumulation in plants grown in fertilized and unfertilized pots, chlorophyll production, and rhizospheric most probable number (MPN) at 60-day interval. The average biomass production and heights of C. speciosus in contaminated treatments were significantly (p < 0.05) lower compared to the unvegetated control. Plants grown in contaminated soil showed relatively reduced root surface area compared to the uncontaminated treatments. TPH degradation in planted fertilized, unplanted, and planted unfertilized pot was 63%, 0.8%, and 38%, respectively. However, compared to unvegetated treatments, TPH degradation was significantly higher (p < 0.05) in vegetated treatments. A comparison of fertilized and unfertilized soils showed that TPH accumulation in plant roots and shoots was relatively higher in fertilized soils. Hg degradation in soil was significantly (p < 0.05) more in planted treatment compared to unplanted treatments. The fertilized soil showed relatively more Hg degradation in soil and its accumulation in roots and shoots of plants in comparison to unfertilized soil. MPN in treatments with plants was significantly greater (p < 0.05) than without plants. The plant's ability to produce biomass, chlorophyll, break down crude oil, reduce Hg levels in soil, and accumulate TPH and Hg in roots and shoots of the plant all point to the possibility of using this plant to remove TPH and Hg from soil.
本研究旨在评估土沉香（Costus speciosus（Koen ex. Retz.）Sm.）在网室内盆栽实验中降解原油和减少受污染土壤中汞（Hg）的效率，为期 180 天。土沉香被移植到含有 19150 mg kg 原油和 3.2 mg kg Hg 的土壤中。该研究包括评估植物生物量、高度、根长、总石油烃（TPH）降解以及施化肥和不施化肥的土壤中 Hg 的还原、植物中 TPH 和 Hg 的积累、叶绿素的产生以及 60 天间隔的根际最可能数（MPN）。与无植被对照相比，受污染处理中土沉香的平均生物量和高度显著（p < 0.05）降低。与无污染处理相比，在受污染土壤中生长的植物的根表面积相对较小。施肥种植、未种植和未施肥种植盆中土的 TPH 降解率分别为 63%、0.8%和 38%。然而，与无植被处理相比，植被处理中的 TPH 降解率显著更高（p < 0.05）。施肥和未施肥土壤的比较表明，在施肥土壤中植物根和地上部分的 TPH 积累相对较高。与未种植处理相比，种植处理中的土壤 Hg 降解显著更高（p < 0.05）。与未施肥土壤相比，施肥土壤中土壤 Hg 降解及其在植物根和地上部分的积累相对较高。有植物的处理中的 MPN 显著大于无植物的处理（p < 0.05）。植物产生生物量、叶绿素、分解原油、降低土壤中 Hg 水平以及在植物根和地上部分积累 TPH 和 Hg 的能力，都表明该植物有可能从土壤中去除 TPH 和 Hg。
