Biochar and compost-based phytoremediation of crude oil contaminated soil

Abstract

Objectives: To study the effect of compost and biochar on phytoremediation of crude oil-contaminated soil. Methods: An attempt was made to remediate crude oil contaminated soil, using the phytoremediation method. The soil was amended with biochar and compost. Initially, the pH, moisture content and C/N ratio of the soil and amendments were determined. A pot culture experiment was conducted to study the effect of the amendments on the degradation of the Total Petroleum Hydrocarbons (TPH) in the crude oil contaminated soil using the plant species nutgrass (Cyperus rotundus). To avoid seepage of water from the pots plastic pots were used. The initial concentration of TPH was found to be 17mg/kg soil. The experiment was conducted from January to March 2019. No microorganism was inoculated either to enhance the growth of the plant or degrade the hydrocarbon. The study was conducted with natural microflora. The pots were kept (open) under direct sunlight with 8 hours of photoperiodism. The plants were watered daily with tap water to maintain optimum moisture content. Once in 15 days, the soil samples collected from each treatment were analysed for pH, moisture content and C/N ratio. The TPH removal rate was determined for the 45 th day and 60 th day. Findings: The soil amended with compost (200 kg/soil) and biochar (50 kg/soil) enhanced the degradation of TPH by the plant species. The highest degradation percent of 62.2 and 77.1% was achieved on 45 th and 60 th day respectively in the treatment T5 (amended with biochar and compost). Further, there was an increase in shoot length (54.52 cm/plant), root biomass (0.74 g/plant) and shoot biomass (5.08g/plant) of the plants in the biochar and compost amended soil which was comparable with the results of the treatment T2 (Plants were grown in soil without crude oil contamination). Applications: Biochar and compost amendment improves the water holding capacity and nutrient status of the soil, thereby enhancing the growth of TPH degraders in soil. Hence, from the study, it is understood that biochar and compost could be used for phytoremediation of crude oil contaminated soils.

Phytoremediation of soils contaminated with crude and weathered oil using two rice varieties (Oryza sativa L.)

“…In general, the negative effect of TPH and TPH 1, observed in the physiological variables (height, and root, aerial and total dry biomass) is attributed to the inhibition caused by the increase in the different concentrations of hydrocarbons in the soil, which suppress the nutrient's availability (Cartmill et al, 2014;Ruley et al, 2019;Omara et al, 2020) and delay the water absorption by plants (Wang et al, 2013;Ruley et al, 2020;Deebika et al, 2021). Likewise, oil hydrocarbons alter the physical properties of soils such as permeability, in addition to suffocating roots, especially in fine-textured (clay) or shallow soils, affecting plant growth (Akinwumi et al, 2014;Grifoni et al, 2020;Ostovar et al, 2021).…”

Biosurfactant-Assisted Phytoremediation of Diesel-Contaminated Soil by Three Different Legume Species

“…Many studies have reported successful implementation of biochar, microbiological inocula, urea, compost, etc. [61][62][63][64][65][66]. Various biosurfactants (BS) have recently received considerable attention as bioremediation-promoting agents [67][68][69].…”

Biochar; an effective factor in improving phytoremediation of metal(iod)s in polluted sites

“…Furthermore, these organic and inorganic modifiers increase phytoremediation efficiency by stimulating microorganisms' activities, increasing plant growth and biomass production (Clemente et al, 2012;Barati et al, 2018;Roohi et al, 2020;Boorboori and Zhang, 2022b). The Frontiers in Environmental Science frontiersin.org following are some of the most important modifiers used in recent years: poultry droppings, cow dung, biochar, rice husk, compost, technocell, steel slag, carbon materials (CMs), and nanomaterials (NMs) (Singh and Lee, 2016;Forján et al, 2018;Lebrun et al, 2021a;Deebika et al, 2021), and in the following, biochar's role in phytoremediation of HMs will be discussed in more detail.…”

“…Phytoremediation can be improved with biochar due to its long-term stability compared to other organic amendments as well as its effective role in improving the soil's physical, chemical, and biological properties (Cárdenas-Aguiar et al, 2019;Ratnasari et al, 2020). By improving soil pH, carbon content, soil aeration, soil fertility, water retention capacity, microbial diversity, and plant growth, biochar is highly effective at cleaning environments contaminated with HMs (Forján et al, 2018;Gong et al, 2019;Deebika et al, 2021). Furthermore, Its high specific surface area, porous structure (macropores and micropores), cation exchange capacity, and active functional groups make biochar an effective tool for stabilizing soil pollution and reducing HMs bioavailability for organisms (Song et al, 2016;Yang et al, 2017a;Zhang et al, 2019a).…”

“…Furthermore, adding lime and sulfur to biochar can reduce HM bioavailability and improve plant growth in the process of phytoremediation (Xu et al, 2018a;Narayanan and Ma, 2022). Studies have also been conducted on the effectiveness of compost and biochar combination in phytoremediation of soil contaminated with HMs (Roohi et al, 2020;Deebika et al, 2021), some of which are listed below. In a study that was conducted to evaluate the potential of B. tomentellus for phytoremediation of soils contaminated with Cr and Zn with the help of biochar treatment and urban waste compost, it was shown that by combining these treatments, HMs absorption by seedlings significantly increased (Roohi et al, 2020).…”