Rapid industrialization and urbanization have generated huge amount of environmental pollution. Especially, synthetic organic chemicals have been a serious international problem for over half a century due to their toxic and hazardous chemicals. Eco-friendly strategies for removing the chemicals from the soil and water are becoming a top priority around the world and biological treatment such as phytoremediation and bioremediation is less expensive and more sustainable than other conventional remediation techniques. Recently, many pollutant diminishing microbial endophytes have been discovered from various plants grown in contaminated area and the function of microbes to improve phytoremediation of organic pollutants has been reported. Thus, we classify synthetic organic pollutants into groups of similar compounds and discuss the contribution of endophytes to enhance phytoremediation.
A phytoremediation study has been conducted to see if some known aquatic plants can remove the pesticides, endosulfan-α, β and fenitrothion which are frequently used in the crop protection and golf course management, and are likely to exist as residual pollutants in the aquatic ecosystems. Among the five aquatic plants tested in the microcosms, water lily Nymphaea tetragona Georgi showed the highest degradation efficacies (85~95%) for the three pesticides as opposed to the control(13~26%). The efficacies for the other plants were in the range of 46~80% in the order of Pistia stratiotes, Cyperus helferi, Eichhornia crassipes, and Iris pseudoacorus. Fenitrothion, an organo-phosphorus pesticide, was much more vulnerable to the phytoremediation than the organo-chlorine pesticides, endosulfan-α and endosulfan-β. The kinetic rate constants (min-1) for removal of the three pesticides were more than 10 times higher than the control (non-planting) in case of Nymphaea tetragona Georgi. This aquatic plant showed kinetic rate constants about 2 times as much as the lower kinetic rate constants shown by Iris pseudoacorus. The reason for the highest degradation efficacy of water lily would be that the plant can live in the sediment and possess roots and broad leaves which could absorb or accumulate and degrade more pollutants in association with microbes. These results indicate that some of the selected aquatic plants planted near the agricultural lands and wetlands could contribute to remediation of pesticides present in these places, and could be applicable to protection of the aquatic ecosystems.
본 연구는 중금속 오염지역의 토양정화에 적합한 식물을 선발하기 위해 국화과 15종을 중금속으로 오염된 토양에 8주 동안 재배한 다음 생육반응과 부위별 비소, 카드뮴, 구리, 납, 아연 등의 중금속의 축적능을 분석하였다. 톱풀을 제외한 가새쑥부쟁이, 금계국, 감국, 각시취 등의 생육은 비교적 양호하였다. 비소 축적능은 더위지기 지하부(25.52 ㎎·㎏-1)에서 가장 높았고 지상부는 바위구절초(3.35 ㎎·㎏-1)가 가장 우수하였다. 카드뮴은 왕갯쑥부쟁이 지상부(2.50 ㎎·㎏-1)에서 가장 높았다. 구리 축적능은 지상부와 지하부 모두 각시취(24.29, 99.92 ㎎·㎏-1)가 가장 높은 경향을 보였다. 국화과 15종의 지상부는 1.43(왕갯쑥부쟁이)∼5.00 ㎎·㎏-1(수리취)의 납이 축적되었다. 눈갯쑥부쟁이(140.09 ㎎·㎏-1), 쑥부쟁이(109.07 ㎎·㎏-1), 왕갯쑥부쟁이(100.21 ㎎·㎏-1) 등의 아연 축적능은 100 ㎎·㎏-1 이상으로 아연 오염 지역의 식물상 정화 기법 소재로 활용이 가능할 것으로 생각된다.
This study was performed to develop the efficient phytoremediation model in the paddy soil contaminated with heavy metals by cultivating Pteris multifida and Artemisia princeps with different mixing ratios (1:0, 8:1, 6:1, 4:1). As a result of investigating the heavy metal accumulation of each plant per dried material (1 ㎏), content of arsenic and cadmium was the highest in aerial part of P. multifida (169.82, 1.70 ㎎·㎏-1 DW, each) among the treated group. Lead content was the highest (12.58 ㎎·㎏-1 DW) in the aerial part of P. multifida cultivated with 8:1 mixed planting. But the content of copper and zinc was the highest (33.94, 61.78 ㎎·㎏-1 DW, each) in the aerial part of A. princeps with 8:1 treatment. Regardless of heavy metals, plant uptake from the 1 ㎡ soil was the highest in 4:1 mixed planting group, which showed the best yield of A. princeps.
Salted-affected soil is a major environmental constraint with severe negative impacts on agricultural productivity and sustainability in reclaimed tidelands. This review focuses on the phytoremediation of reclaimed tidelands. We address the process of phytoremediation of these soils, comparison of phytoremediation with other amelioration approaches, driving forces contributing to the process, selection of phytoremediation crops, and the role of cropping in securing environmental integrity under salt-affected soils.
however, these elements can limit plant growth. This study selected a heavy metal-tolerant plant by analyzing seed germination and biomass of alfalfa (Medicago sativa), canola (Brassica campestris subsp. napus var. nippo-oleifera), Chinese corn (Setaria italica), and a sorghum-sudangrass hybrid (Sorghum bicolor × S. sudanense), and determined heavy metal uptake capacity by analyzing biomass, chlorophyll a fluorescence, and heavy metal contents under high external copper or zinc levels. The seed germination rate and biomass of the sorghum-sudangrass hybrid were higher under copper or zinc stress compared to the other three plants. The plant biomass and photosynthetic pigment contents of the sorghum-sudangrass hybrid seedlings were less vulnerable under low levels of heavy metals (≤ 50 ppm copper or ≤ 400 ppm zinc). The maximum quantum yield of PSII (Fv/Fm) and the maximum primary yield of PSII (Fv/Fo) decreased with increasing copper or zinc levels. Under high copper levels, the decline in Fv/Fm was caused only by the decline in Fm, and was accompanied by an increase in non-photochemical quenching (NPQ). The Fv/Fm declined under high levels of zinc due to both a decrease in the maximum fluorescence (Fm) and an increase in the initial fluorescence (Fo), and this was accompanied by a marked decrease in photochemical quenching (qP), but not by an increase in NPQ. Accumulations of copper and zinc were found in both aboveand below-ground parts of plants, but were greater in the below-ground parts. The uptake capacity of the sorghum-sudangrass hybrid for copper and zinc reached 4459.1 mg/kg under 400 ppm copper and 9028.5 mg/kg under 1600 ppm zinc. Our results indicate that the sorghum-sudangrass hybrid contributes to the in situ phytoremediation of copper or zinc polluted soils due to its high biomass yield.
This study attempted to utilize various groundcover plants in phytoremediation, using shade plants, which often have a high shade tolerance for shade urban space. Liriope platyphylla was grown in soil containing three of heavy metals, Zn, Cd, and Pb under four different concentrations (0, 100, 250 and 500 mg/kg) to determine the heavy metal accumulation characteristics and removing from soil. Total amounts of accumulated Zn in L. platyphylla were increased in accordance with increasing elevated Zn concentrations in soil, but the difference was not significant between Zn250 and Zn500. Cd accumulation, sharply increased in Cd100 and Cd250, but was reduced in Cd500. Increased Pb concentration in soil resulted a continuous increase in the total amounts of Pb accumulated in L. platyphylla. The total content of Zn in soil decreased by almost 50% in Zn100, almost 33% in Zn250 and 20% in Zn500 through growth of L. platyphylla over a period of 7 months. In the case of Cd, the concentration in soil, was decreased with 10% in Cd100, 10% in Cd250 and 33% in Cd500 through growth of L. platyphylla over a period of 7 months. This results indicate that more Cd was removed by planting L. platyphylla, compared to Zn or Pb.
본 연구는 환경친화적인 중금속 정화방법인 식물복원법(phytoremediation)의 적합성 규명을 위해 경관적 가치를 제공할 수 있는 조경수인 개나리(Forsythia koreana Nakai), 명자나무(Chaenomeles speciosa Koidz) 와 쥐똥나무(Ligustrum obtusifolium )Sieb. et Zucc.의 Cd처리에 따른 생육량과 생리적 특성을 조사하였고, 식물체내의 중금속 축적량을 확인하여 중금속 오염지에 대한 식물복원 개량대책을 위한 가능성을 알아보고자 실시하였다. 생장반응에 있어 Cd의 영향은 생장량의 감소현상은 뚜렷하였으며, 쥐똥나무 경우 6월 7일경에 무처리구는 신초장 60.10cm를 보였으나, Cd 처리구는 11.50cm로 생육이 감소하였다. 한편 명자나무에서는 Cd 처리구에서 가장 생육이 극히 부진하여 Cd에 내성이 약한 것으로 나타났다. 또한 Cd 처리에 따른 생리적 특성에 있어 엽록소 함량은 개나리에 있어 Cd 처리구에서 3.36 mg/g으로 4.85 mg/g인 대조구에 비해 현저하게 감소하였고, 쥐똥나무에서도 4.17mg/g에서 2.57mg/g으로 현저한 감소하는 경향을 보였다. 또한 TSC 함량의 변화는 엽록소의 변화에 매우 유사한 경향을 보였다. Cd 처리에 따른 전 질소 함량의 변화는 쥐똥나무의 Cd 처리구에서 가장 낮은 6.82를 보였다. 한편 soluble protein 함량에 있어서는 모두 Cd 처리구에서는 대조구와 큰 차이가 없었다. 한편 Cd에 대한 조사대상 식물들의 축적정도는 개나리에 있어 10.36ppm인 지하부의 Cd 중금속의 축적량은 2.37ppm인 지상부에 비해 4.3배 정도 많았고, 명자나무는 지상부 1.06ppm에 비해 지하부가 7.17ppm로 6.7배이며, 쥐똥나무는 지상부 함량이 3.23ppm인 반면에, 지하부가 5.12 ppm으로 1.5배로 높게 나타냄을 알 수 있다. 식물체의 지하부 축적량을 비교하면 개나리>명자나무> 쥐똥나무 순으로 볼 수 있으나, 지상부에서는 쥐똥나무>개나리>명자나무 순으로 중금속의 축적량이 가장 많았다.
본 연구는 환경친화적인 중금속 정화방법인 식물복원법(phytoremediation)의 적합성 규명을 위해 미적 가치를 제공할 수 있는 조경식물로 코스모스와 해바라기를 이용하였고, Cu와 Cd의 중금속을 농도별로 처리하여 생육량과 생리적 특성을 조사하였고, 식물체내의 중금속 축적량을 확인하여 식물복원법 적용의 타당성을 제안하고자 실시하였다.농도별 중금속 처리에 있어서 그 처리 농도가 높을수록 생육량이 불량하였고 엽록소 함량은 대조구에 비해 Cu처리에서 다소 높았고 Cu 처리농도가 높을수록 증가하였으며 Cd 처리에 있어서는 그 함량이 감소하였다. 수용성 단백질 함량은 저농도의 중금속 처리에서는 대조구와 큰 차이가 없었지만 Cu 2000μM과 Cd 100μM에서 그 함량이 감소하였다. 전질소 함량은 Cu 2000μM에서 가장 저조하였고, 엽록소와 수용성 단백질과는 달리 생육기간이 경과할 수록 그 함량이 감소되는 경향을 보였다. 중금속의 처리 농도가 증가할수록 생육량과 생리적 양상에서 다소 저해를 보였지만 축적량이 증가하는 경향을 보였고, 지상부에 비해 지하부의 축적량이 많았으며 식물체내의 중금속 축적량은 코스모스는 뿌리에서 Cu 453.44μg/g, Cd 675.14μg/g이었고, 해바라기는 뿌리에서 Cu 353.14μg/g, Cd 140.76μg/g으로 그 축적량이 양호하였다. 따라서 코스모스와 해바라기는 경관조성이 가능한 phytoremediator로서의 가능성이 있을 것이라 생각된다.