Sun Y.-B.,Tianjin Key Laboratory of Agro Environment and Food Safety |
Xu Y.-M.,Tianjin Key Laboratory of Agro Environment and Food Safety |
Shi X.,Jilin University |
Wang L.,Tianjin Key Laboratory of Agro Environment and Food Safety |
And 2 more authors.
Zhongguo Huanjing Kexue/China Environmental Science | Year: 2012
Pot experiment was conducted to investigate the effects of sepiolite on stabilization remediation of Cd contaminated soils in wastewater irrigation region and soil environmental quality. Results showed that the addition of sepiolite significantly decreased the concentration of TCLP-Cd in soil, the ratio of Cd exchangeable fraction reduced by 0.8%~3.8% when compared with the control, while the percentage of residual form of Cd increased by 0.5%~9.8%. However, the treatments of sepiolite significantly increased the biomass of spinach, resulting in 0.94~2.11 times increase for shoot biomass and 1.63~5.21 times increase for root biomass, respectively, in contrast to the control group. The activities of catalase, urease and invertase after applying sepiolite increased by 5.1%~15.4%, 14.2%~28.8% and 23.5%~34.0%. And the amount of bacteria and fungi enhanced by 15.5%~91.7% and 45.6%~96.5%, respectively. The concentration of Cd in the shoots and roots and Cd bioaccumulation and translocation factors of spinach decreased with increasing of sepiolite, suffering by 19.9%~45.6% and 51.2%~70.2% reduction, respectively. when compared to CK. The Cd content in the editable parts of spinach met with the national standard of hygiene quality for vegetable (GB 2762-2005) when the treatment of sepiolite was up to 5%.
Ding Y.Z.,Agro Environmental Protection Institute |
Ding Y.Z.,Key Laboratory of Production Environment and Agro product Safety |
Ding Y.Z.,Tianjin Key Laboratory of Agro environment and Food Safety |
Song Z.G.,Agro Environmental Protection Institute |
And 8 more authors.
International Journal of Environmental Science and Technology | Year: 2014
Vegetation at mining sites can produce increased heavy metal leaching by the organic acids and protons originating from root secretion and litter degradation. Batch experiments were conducted to investigate the effects of organic acids and pH on the extraction of Pb, Cd, Zn and Cu from an alkaline mine soil (sampled from a mining site of Chenzhou City, Hunan Province) and an acid mine soil (sampled from a mining site of Daxin county, Guangxi Province). The results showed that in the presence of organic acids (acetic, oxalic, malic, fumaric, tartaric and citric acids) at pH 7, the extraction of Pb, Cd, Zn and Cu from the acid mine soil was much higher than that from the alkaline mine soil, in which only citric acid with higher concentration was capable of extracting some heavy metals. Citric acid had the strongest ability in extracting heavy metals, followed by oxalic acid. Heavy metal extraction dramatically decreased with increasing pH. Moreover, at low pH, oxalic acid promoted the risk of Cu leaching; at high pH, the leaching of Pb, Zn, Cd and Cu was enhanced by both oxalic and citric acids. This indicated that those plants, which can produce substantial citric acid or oxalic acid by root secretion and litter degradation, should not be selected for the revegetation of mining sites. © 2013 Islamic Azad University (IAU).
Elevated CO 2 increases Cs uptake and alters microbial communities and biomass in the rhizosphere of Phytolacca americana Linn (pokeweed) and Amaranthus cruentus L. (purple amaranth) grown on soils spiked with various levels of Cs
Song N.,Agro Environmental Protection Institute |
Song N.,Key Laboratory of Production Environment and Agro product Safety of Ministry of Agriculture |
Song N.,Tianjin Key Laboratory of Agro environment and Food Safety |
Zhang X.,Agro Environmental Protection Institute |
And 11 more authors.
Journal of Environmental Radioactivity | Year: 2012
General concern about increasing global atmospheric CO 2 levels owing to the ongoing fossil fuel combustion and elevated levels of radionuclides in the environment, has led to growing interest in the responses of plants to interactive effects of elevated CO 2 and radionuclides in terms of phytoremediation and food safety. To assess the combined effects of elevated CO 2 and cesium contamination on plant biomass, microbial activities in the rhizosphere soil and Cs uptake, Phytolacca americana Linn (pokeweed, C3 specie) and Amaranthus cruentus L. (purple amaranth, C4 specie) were grown in pots of soils containing five levels of cesium (0, 100, 300, 500 and 1000 mg Cs kg -1) under two levels of CO 2 (360 and 860 μL L -1, respectively). Shoot and root biomass of P. americana and Amaranthus crentus was generally higher under elevated CO 2 than under ambient CO 2 for all treatments. Both plant species exhibited higher Cs concentration in the shoots and roots under elevated CO 2 than ambient CO 2. For P. americana grown at 0, 100, 300, 500 and 1000 mg Cs kg -1, the increase magnitude of Cs concentration due to elevated CO 2 was 140, 18, 11, 34 and 15% in the shoots, and 150, 20, 14, 15 and 19% in the roots, respectively. For A. cruentus, the corresponding value was 118, 28, 21, 14 and 17% in the shoots, and 126, 6, 11, 17 and 22% in the roots, respectively. Higher bioaccumulation factors were noted for both species grown under elevated CO 2 than ambient CO 2. The populations of bacteria, actinomycetes and fungi, and the microbial C and N in the rhizosphere soils of both species were higher at elevated CO 2 than at ambient CO 2 with the same concentration of Cs. The results suggested that elevated CO 2 significantly affected plant biomass, Cs uptake, soil C and N concentrations, and community composition of soil microbes associated with P. americana and A. cruentus roots. The knowledge gained from this investigation constitutes an important advancement in promoting utilization of CO 2 fertilization for improvement of phytoextraction of soils contaminated with radionuclides. © 2012.