Different agricultural practices can be beneficial in Miscanthus × giganteus (M × g) phytotechnology applied to post-military and post-mining lands. However, only limited research has focused on supportive treatments using biochar produced from M × g waste. Indeed, when M × g phytotechnology is applied to contaminated soil, the biochar produced through the pyrolysis of the obtained biomass is contaminated, raising concerns about its further application. The current study tested the use of biochar produced from M × g roots cultivated long-term in slightly contaminated soil in the M × g phytotechnology of Cu- or Zn-spiked soils which is important for finding the solution toward valorization of the contaminated biomass. Two biochar doses (1.67 and 5.00%) were evaluated with varying levels of Cu (200 to 416 mg kg-1) or Zn (202 to 580 mg kg-1) concentrations in the soils. This study revealed a beneficial influence of biochar on M × g development, specifically by increasing the plant height and aboveground biomass by up to 20.4 and 115%, respectively. However, the root dry weight increased by 31.8% only at the highest application rate of biochar. The option for valorization of the contaminated biochar in the next phytoremediation process applied to soil contaminated more than the biochar itself was tested. The finding showed the positive influence of biochar on the M × g phytoremediation metrics such as tolerance index, bioconcentration factor, translocation factor, and comprehensive bioconcentration index which ensured the perspective of the proposed approach in the implementation of post-remediation management practice.
- Klíčová slova
- Miscanthus × giganteus, Bioparameters, Phytoremediation metrics, Pyrolysis, Waste biomass,
- MeSH
- biomasa MeSH
- dřevěné a živočišné uhlí * chemie MeSH
- látky znečišťující půdu * MeSH
- lipnicovité * MeSH
- měď * MeSH
- půda * chemie MeSH
- zinek * MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- biochar MeSH Prohlížeč
- dřevěné a živočišné uhlí * MeSH
- látky znečišťující půdu * MeSH
- měď * MeSH
- půda * MeSH
- zinek * MeSH
The effect of inoculation of Miscanthus × giganteus Greef et Deu by the plant growth promoting rhizobacteria (PGPRs) to the phytoremediation process and physio-biochemical plant's parameters was investigated in soil contaminated with the trace elements (TEs) from the Tekeli mining complex, Kazakhstan. Yeast Trichosporon sp. CA1, strains Rhizobium sp. Zn1-1, Shinella sp. Zn5-6, and Pseudomonas sp. CHA1-4, resistant to Zn and Pb, were isolated from the rhizosphere of M × g when the plant was cultivated in the same contaminated soil. Results illustrated that inoculation improved M × g adaptability to TEs toxicity by increasing the tolerance index to 2.9. The treatment enhanced the aboveground biomass yield by up to 163%, root biomass by up to 240%, chlorophyll content by up to 30%, and Chla/b ratio by up to 21%. Through M × g active growth and development, the peak activity of antioxidant enzymes was observed: activity of superoxide dismutase and glutathione reductase was induced, while the activity of catalase and ascorbate peroxidase was inhibited. Based on bioconcentration and translocation factors it was revealed that PGPRs selectively increased the uptake of TEs or stabilised them in the M × g rhizosphere. Inoculation with PGPRs increased the stabilization of Pb, V, Cr, Co, Ni, Cu, Cd, As, and Ba in the soil and plant tissues. Further research should focus on ex situ experiments using isolated PGPRs.
- Klíčová slova
- Antioxidative enzymes, Chlorophyll fluorescence, Miscanthus × giganteus, PGPRs, Phytoremediation, Tolerance index,
- MeSH
- biodegradace MeSH
- kořeny rostlin chemie MeSH
- látky znečišťující půdu * analýza MeSH
- lipnicovité fyziologie MeSH
- olovo analýza MeSH
- půda chemie MeSH
- rostliny MeSH
- stopové prvky * analýza MeSH
- těžké kovy * analýza MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- látky znečišťující půdu * MeSH
- olovo MeSH
- půda MeSH
- stopové prvky * MeSH
- těžké kovy * MeSH
Paulownia tomentosa (Thunb.) Steud is a drought-resistant, low-maintenance and fast-growing energy crop that can withstand a wide range of climatic conditions, provides a high biomass yield (approximately 50 t DM ha-1 yr-1), and develops successfully in contaminated sites. In Kazakhstan, there are many historically contaminated sites polluted by a mixture of xenobiotics of organic and inorganic origin that need to be revitalised. Pilot-scale research evaluated the potential of P. tomentosa for the phytoremediation of soils historically contaminated with organochlorine pesticides (OCPs) and toxic trace elements (TTEs) to minimise their impact on the environment. Targeted soils from the obsolete pesticide stockpiles located in three villages of Talgar district, Almaty region, Kazakhstan, i.e., Amangeldy (soil A), Beskainar (soil B), and Kyzylkairat (soil K), were subjected to research. Twenty OCPs and eight TTEs (As, Cr, Co, Ni, Cu, Zn, Cd, and Pb) were detected in the soils. The phytoremediation potential of P. tomentosa was investigated for OCPs whose concentrations in the soils were significantly different (aldrin, endosulfans, endrin aldehyde, HCB, heptachlor, hexabromobenzene, keltan, methoxychlor, and γ-HCH) and for TTEs (Cu, Zn, and Cd) whose concentrations exceeded maximum permissible concentrations. Bioconcentration (BCF) and translocation (TLF) factors were used as indicators of the phytoremediation process. It was ensured that the uptake and translocation of contaminants by P. tomentosa was highly variable and depended on their properties and concentrations in soil. Besides the ability to bioconcentrate Cr, Ni, and Cu, P. tomentosa demonstrated very encouraging results in the accumulation of endosulfans, keltan, and methoxychlor and the phytoextraction of γ-HCH (TLFs of 1.9-9.9) and HCB (BCFs of 197-571). The results of the pilot trials support the need to further investigate the potential of P. tomentosa for phytoremediation on a field scale.
- Klíčová slova
- Paulownia tomentosa, bioconcentration factor, organochlorine pesticides, phytoremediation, toxic trace elements, translocation factor,
- Publikační typ
- časopisecké články MeSH
To complete a loop of the Miscanthus value chain including production, phytomanagement, conversion to energy, and bioproducts, the wastes accumulated from these processes have to be returned to the production cycle to provide sustainable use of the feedstock, to reduce costs, and to ensure a zero-waste approach. This can be achieved by converting Miscanthus feedstock into biogas and biochar using pyrolysis and then returning biochar to the production cycle of Miscanthus crop applications in the phytotechnology of trace elements (TEs)-contaminated/marginal lands. These processes are subjects of the current review, which focused on the peculiarities of biochar received from Miscanthus by pyrolysis, its properties, the impact on soil characteristics, the phytoremediation process, biomass yield, and the abundance of soil biodiversity. Results from the literature indicated that the pH, surface area, and porosity of Miscanthus biochar are important in determining its impact on soil characteristics. It was inferred that the most effective Miscanthus biochar was produced with a pyrolysis temperature of about 600 °C with a residence time from about 30 min to an hour. Another important factor that determined the impact of Miscanthus biochar on soil health is the application rate: with its increase, the effect became more essential, and the recommended rate is between 5% and 10%. The influence of Miscanthus biochar on the TEs phytoremediation parameters is less studied, generally Miscanthus biochar produced at higher temperatures and added with higher application rates is more likely to restrict the mobility and availability of TEs by different plants. However, some published results are contradictory to these conclusions and showed absence of significant difference in TEs reduction during application of different Miscanthus biochar doses. The future experimental studies have to focus on determining the impact of a technological pyrolysis regime on Miscanthus biochar properties on TEs-contaminated or marginal land when biochar will be obtained from contaminated rhizomes and waste after the application of phytotechnology. In addition, studies must explore the influence of this biochar on TEs phytoparameters, enhancements in biomass yield, improvements in soil parameters, and the abundance of soil diversity.
- Klíčová slova
- Application rate, Biomass, Miscanthus biochar, Phytoremediation, Pyrolysis, Zero-waste approach,
- MeSH
- biomasa MeSH
- dřevěné a živočišné uhlí * MeSH
- lidé MeSH
- lipnicovité MeSH
- půda * MeSH
- pyrolýza MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
- Názvy látek
- biochar MeSH Prohlížeč
- dřevěné a živočišné uhlí * MeSH
- půda * MeSH
The organochlorine pesticides (OCPs) have raised concerns about being persistent and toxic to the environment. Phytoremediation techniques show promise for the revitalization of polluted soils. The current study focused on optimizing the phytoremediation potential of Miscanthus sinensis And. (M. sinensis), second-generation energy crop, by exploring two soil amendments: Tween 20 and activated carbon (AC). The results showed that when M. sinensis grew in OCP-polluted soil without amendments to it, the wide range of compounds, i.e., α-HCH, β-HCH, γ-HCH, 2.4-DDD, 4.4-DDE, 4.4-DDD, 4.4-DDT, aldrin, dieldrin, and endrin, was accumulated by the plant. The introduction of soil amendments improved the growth parameters of M. sinensis. The adding of Tween 20 enhanced the absorption and transmigration to aboveground biomass for some OCPs; i.e., for γ-HCH, the increase was by 1.2, for 4.4-DDE by 8.7 times; this effect was due to the reduction of the hydrophobicity which made pesticides more bioavailable for the plant. The adding of AC reduced OCPs absorption by plants, consequently, for γ-HCH by 2.1 times, 4.4-DDD by 20.5 times, 4.4-DDE by 1.4 times, 4.4-DDT by 8 times, α-HCH was not adsorbed at all, and decreased the translocation to the aboveground biomass: for 4.4-DDD by 31 times, 4.4-DDE by 2.8 times, and γ-HCH by 2 times; this effect was due to the decrease in the bioavailability of pesticides. Overall, the amendment of OCP-polluted soil by Tween 20 speeds the remediation process, and incorporation of AC permitted to produce the relatively clean biomass for energy.
- Klíčová slova
- Activated carbon, Miscanthus sinensis And., Organochlorine pesticides, Phytoremediation, Sequestration, Tween 20,
- MeSH
- biodegradace MeSH
- chlorované uhlovodíky * analýza MeSH
- dřevěné a živočišné uhlí MeSH
- látky znečišťující půdu * analýza MeSH
- monitorování životního prostředí MeSH
- pesticidy * analýza MeSH
- polysorbáty MeSH
- půda MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- chlorované uhlovodíky * MeSH
- dřevěné a živočišné uhlí MeSH
- látky znečišťující půdu * MeSH
- pesticidy * MeSH
- polysorbáty MeSH
- půda MeSH
