• Korean Journal of Soil Science and Fertilizer
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• v.37 no.1
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• pp.14-18
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• 2004

This study was aimed at searching for the wintering Cd hyperaccumulators as the life cycle of existing hyperaccumulators were mostly from spring to early winter season. The wintering hyperaccumulators can be effective for saving time loss during the winter. A pot experiment was conducted to search for hyperaccumulators through out the native wintering plants. Seven species of native wintering plants were applied; Bromus catharticus, Oxatis corniculata, Festuca rubra, Thlaspi. arvense, Agastache rrgosa, Viola seoulensis, and Patrinia rapestris. Among them, Bromus catharticus and Thlaspi arvense were selected as Cd hyperaccumulators; the two plants accumulated 112.35 and $86.69mg\;kg^{-1}$ of Cd in the shoot, respectively.

• Journal of Korea Soil Environment Society
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• v.2 no.1
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• pp.3-12
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• 1997

Phytoremediation, using plants to remediate toxic organic and inorganic pollutants in contaminated soils, is an emerging technology for environmental cleanup. Three strategies of this technology are applicable to the remediation of toxic heavy metals, radionuclides, and toxic organic pollutants: They are (1) phytoextraction, in which plants anumulate the contaminants and are harvested for the downstream processing; (2) phytodegradation, in which plant-released enzymes or plant-associated microorganisms convert toxic pollutants into non-toxic materials; and (3) phytostabilization, in which toxic pollutants are precipitated from solution or absorbed in either the plant tissue or the soil matrix. Phytoremediation is more effective and less expensive than other current treatment technologies.

• Proceedings of the Korean Society of Plant Biotechnology Conference
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• 2005.11a
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• pp.191-191
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• 2005

• Journal of Soil and Groundwater Environment
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• v.16 no.5
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• pp.1-8
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• 2011

This study was performed to evaluate the remediation efficiency by Helianthus annuus, Brassica juncea and Brassica campestris on the soil contaminated with nickel, zinc and lead, respectively. The growth rates fell down under 60% in the condition of over 700 mg/kg of zinc for Brassica campestris, 300 mg/kg of lead for Helianthus annuus, and 150 mg/kg of nickel for Brassica juncea on the basis of heavy metal concentration in the soil, because of its toxicity. Also, the hyperaccumulators showed the maximum heavy metal contents in their biomass after 90 days of cultivation. The accumulated heavy metal content per kilogram of hyperaccumulator was 0.65 mg of nickel in Brassica juncea, 0.14 mg of zinc in Brassica campestris, and 0.06 mg of lead in Helianthus annuus, respectively. Additionally, 73.2% of nickel accumulated in Brassica juncea and 95.1% of zinc accumulated in Brassica campestris were concentrated in the upper site of crop like stem and leaves. However, in the case of Helianthus annuus, 83.7% of lead was accumulated in the root.

• Proceedings of the KSEEG Conference
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• 2003.04a
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• pp.72-75
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• 2003

Plant species have shown the capability to absorb U into the biomass. Norman(l952) even suggested that uranyl ion acts as an accessory microelement in growth of Lemna and flax roots. The plants, termed metal hyperaccumulators, can extract and accumulate more than 1000-10,000mg heavy metal per kilogram of dry weight of plants (0.1-1%). The most vital main factors influencing the ability and efficiency of phytoremediation is the ability of the plant to uptake the metals from soil before the accumulation mechanism happens in the plant tissue. (omitted)

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.4
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• pp.280-291
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• 2007

Much research has been conducted in the field of phytoremediation since the discovery of the range of plants known as hyperaccumulators. Research has focused simultaneously on elucidating the mechanism of metal(loid) accumulation and development of practical techniques to enhance accumulation efficiency. To date, it is generally understood that there are five specific mechanisms employed by hyperaccumulating plant species that are either not or under utilized by non-hyperaccumulators. These include 1) enhanced metal(loid)s uptake through the root cell, 2) enhanced translocation in plant tissue, 3) detoxification and sequestration, 4) enhanced metal availability in soil:root interface, and 5) active root foraging toward metal(loid) enriched soils. Among these mechanisms, understanding of the plant-root effect on metal(loid) dynamics and subsequent plant uptake is vital to overcome the inherit limitation of phytoremediation caused by low metal(loid) solubility in soils. Plant roots can influence the soil chemistry in the rhizosphere through changes in pH and exudation of organic compounds such as low-molecular-weight organic acids (LMWOAs) which consequently change metal(loid) solubility. The decrease in soil pH by plant release of $H^+$ results in increased metal solubility. Elevated levels of organic compounds in response to high metal soil concentrations by plant exudation may also increases metal concentration in soil solution through formation of organometallic complexes.

• Environmental Engineering Research
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• v.19 no.2
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• pp.145-149
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• 2014

Arsenic (As) is one of the heavy metals which causes acute bio-toxicity even at low concentration and has disastrous effect on environment. In some countries, As contamination has become alarming and increasing day by day as consequences of unsustainable management practices. Many existing physical, chemical and biological processes for As removal from water system are not feasible due to techno-economic limitations. The present study highlights the scope of biological strategy for As removal through phytoextraction. Arsenic uptake and accumulation in the biomass of three plant species and their As tolerance abilities have been investigated to develop an efficient phytoextraction system in combination of these plant species. Three non-crop plant species, Pteris vittata; Mimosa pudica, and Eichhornia crassipus were treated with 0-200 mg/L As in liquid nutrient solution for 14 days. P. vittata accumulated total 9,082.2 mg (8,223 mg in fronds) As/kg biomass and Eichhornia total 6,969 mg (4,517 mg in fronds)/kg biomass at 200 mg/L As concentration, respectively. Bioaccumulation factor (BF) and translocation factor (TF) were estimated to differentiate between excluders, accumulators and accumulation in above ground biomass. Pteris and Eichhornia have highest BF (67 and 17) and TF (64 and 3), respectively. In contrast, Mimosa accumulated up to 174 mg As/kg plant biomass which is low in comparison with other two plants, and both BF and TF were ${\leq}1$. This study reveals that Pteris and Eichhornia are As hyperaccumulator, and potential candidates for As removal from water system.

• Journal of Microbiology and Biotechnology
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• v.25 no.8
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• pp.1205-1215
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• 2015

Arbuscular mycorrhizal fungi (AMF) have great potential for assisting heavy metal hyperaccumulators in the remediation of contaminated soils. However, little information is available about the symbiosis of AMF associated with an antimony (Sb) accumulator plant under natural conditions. Therefore, the objective of this study was to investigate the colonization and molecular diversity of AMF associated with the Sb accumulator ramie (Boehmeria nivea) growing in Sb-contaminated soils. Four Sb mine spoils and one adjacent reference area were selected from Xikuangshan in southern China. PCR-DGGE was used to analyze the AMF community composition in ramie roots. Morphological identification was also used to analyze the species in the rhizosphere soil of ramie. Results obtained showed that mycorrhizal symbiosis was established successfully even in the most heavily polluted sites. From the unpolluted site Ref to the highest polluted site T4, the spore numbers and AMF diversity increased at first and then decreased. Colonization increased consistently with the increasing Sb concentrations in the soil. A total of 14 species were identified by morphological analysis. From the total number of species, 4 (29%) belonged to Glomus, 2 (14%) belonged to Acaulospora, 2 (14%) belonged to Funneliformis, 1 (7%) belonged to Claroideoglomus, 1 (7%) belonged to Gigaspora, 1 (7%) belonged to Paraglomus, 1 (7%) belonging to Rhizophagus, 1 (7%) belonging to Sclervocystis, and 1 (7%) belonged to Scutellospora. Some AMF sequences were present even in the most polluted site. Morphological identification and phylogenetic analysis both revealed that most species were affiliated with Glomus, suggesting that Glomus was the dominant genus in this AMF community. This study demonstrated that ramie associated with AMF may have great potential for remediation of Sb-contaminated soils.