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Woody species Rhus chinensis Mill. seedlings tolerance to Pb: Physiological and biochemical response
Xiang Shi Shufeng Wang Dongxue Wang Haijing Sun Yitai Chen Jianfeng Liu Zeping Jiang 《环境科学学报(英文版)》2019,31(4):63-73
Screening potential plant species is a crucial consideration in phytoremediation technology. Our previous study demonstrated that Rhus chinensis Mill. seedlings had potentials for phytoremediation of Pb contaminated soil. However, its bioaccumulation and tolerance characteristics remain unclear. Seedling growth, LMWOAs secreted by roots, Pb subcellular distribution and chemical forms, and mineral elements in R. chinensis tissues were evaluated under different Pb concentrations (0, 25, 50, 100, 200 and 400?mg/L) in culture solution at 14?days after planting. R. chinensis did not show visual symptoms of Pb toxicity under lower Pb treatments; however, Pb significantly declined the growth of seedlings under higher Pb treatments. Higher Pb stress also decreased the concentrations of nitrogen in leaves, but increased the concentrations of P and K in roots. Pb stress also decreased Mn concentrations in leaves. A great quantity of Pb was uptake and mostly retained in R. chinensis roots. Nonetheless, R. chinensis can still concentrate 459.3 and 1102.7?mg/kg Pb in leaves and stems, respectively. Most of Pb in R. chinensis tissues was stored in the cell wall with HAc-, HCl-, and NaCl-extractable form. LMWOAs secreted by R. chinensis roots showed a strong positive correlation with Pb concentrations in all plant tissues and with P in roots. Our results suggested that Pb deposited in the cell wall and integration with phosphate or oxalate might be responsible for the tolerance of R. chinensis under Pb stress in short period. 相似文献
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Marcos Rubal Matías H. Medina 《Environmental pollution (Barking, Essex : 1987)》2009,157(10):2751-2758
The study presented here searched for the level of taxonomic resolution required to detect the effects of low-level chronic pollution on estuarine meiobenthic communities. Meiofauna from two sites, with special attention to harpacticoid copepods, was analysed at different taxonomic levels of aggregation using uni- and multivariate methods. Adaptation processes that could buffer biodiversity disruptions were also considered through the analysis of fitness-related and tolerance traits in the harpacticoid copepod Paronychocamptus nanus. Results showed that uni- and multivariate analyses could be inadequate when assessing subtle anthropogenic contamination. Instead, the assessment of inter-population differences in tolerance to the main source of stress rises as a required procedure if potential effects of this type of contamination are being investigated. Specifically, a 96 h acute toxicity test performed with populations from the affected site appears as a faster and reliable general tool to assess impacts of low-level chronic pollution in estuaries. 相似文献
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A Cu tolerant population of the earthworm Dendrodrilus rubidus (Savigny, 1862) at Coniston Copper Mines, Cumbria, UK 总被引:1,自引:0,他引:1
Dendrodrilus rubidus were sampled from a mine spoil soil at Coniston Copper Mine, an abandoned Cu mine in Cumbria, UK and a Cu-free control site. Earthworms were maintained for 14d in both Kettering loam and a Moorland soil amended with Cu nitrate. Mortality, condition index, weight change and tissue concentration were determined. In both soils D. rubidus native to the mine site were able to tolerate significantly higher soil Cu concentrations (MWRT, p相似文献
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Biscutella laevigata is an herbal member of the Brasicacae family and a typical mountain species. It has recently been identified as a hyperaccumulator of lead, cadmium and thallium. Its northern reach runs through Poland, where it is found only in the west Tatra Mountains and on calamine waste heaps in the vicinity of Olkusz (Cracow––Silesian Highland). The peculiar distribution of this species in Poland prompted us to undertake studies to identify the traits that allow this typically mountain species to grow so robustly on industrial waste heaps near zinc and lead smelters in the vicinity of Olkusz. Populations of B. laevigata from waste heaps and the Tatra Mountains were compared both under field (natural) conditions and during cultivation of successive generations under laboratory conditions. It was found that the mountain and waste-heap populations of B. laevigata differed significantly. The plants in the mountain population had thicker leaves covered with cutin and a small number of hairs, whereas the plants from the waste-heap population had thin leaves covered with numerous hairs. The difference in leaf thickness between the two populations (0.15 mm on average) was due to increased dimensions of palisade mesophyl cells whereas the number of cells in their leaves remained similar. These traits were hereditary. This indicates that two geographically distant populations of plants followed two different evolutionary paths to adapt to xerothermic conditions. Moreover, it was shown that the waste-heap population of B. laevigata is more tolerant to heavy metals (lead, zinc and cadmium). In the presence of both zinc and lead, growth of the waste-heap plants was stimulated, while under the same conditions, growth of the mountain population was inhibited lower than 50%. This adaptation facilitates the growth of this population on industrial waste heaps. Our studies show that B. laevigata is a valuable species very well-suited for use in the recultivation of areas containing high levels of heavy metals––the waste-heap population of this species is particularly valuable. 相似文献
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The cladoceran Daphnia magna was acclimated for seven generations to cadmium concentrations ranging from 0 (control) to 250 microg/l Cd (corresponding to a free ion activity of 4.60 nM Cd2+). Acute and chronic cadmium tolerance as well as cadmium accumulation were monitored as a function of acclimation time. After two to three generations of acclimation to concentrations ranging from 0.23 to 1.11 nM Cd2+ increases in acute tolerance were maximal (factor 7.2) and significant. Acclimation for seven generations to the same acclimation concentrations did result in an increased chronic cadmium tolerance (21 days EC50 values increased). Organisms acclimated to 1.93 nM Cd2+ were equally or more sensitive than non-acclimated daphnids in acute and chronic toxicity tests. Cadmium contents in D. magna increased significantly as a function of the acclimation concentration. Maximum body burdens of 236+/-30 microg Cd/g dry weight were measured in organisms exposed to 4.60 nM Cd2+, but detoxification mechanisms were only successful up to 82+/-20 microg Cd/g dry weight as this concentration did not cause major decreases in survival and reproduction in chronic toxicity tests. As the potential positive effect of acclimation on cadmium tolerance disappeared with successive acclimation generations and increasing acclimation concentrations, it is concluded that multi-generation acclimation studies are important for the evaluation of the long-term effects of environmental toxicants. 相似文献
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Root porosity and radial oxygen loss related to arsenic tolerance and uptake in wetland plants 总被引:5,自引:0,他引:5
The rates of radial oxygen loss (ROL), root porosity, concentrations of arsenic (As), iron (Fe) and manganese (Mn) in shoot and root tissues and on root surfaces, As tolerances, and their relationships in different wetland plants were investigated based on a hydroponic experiment (control, 0.8, 1.6 mg As L−1) and a soil pot trail (control, 60 mg As kg−1). The results revealed that wetland plants showed great differences in root porosity (9-64%), rates of ROL (55-1750 mmo1 O2 kg−1 root d.w. d−1), As uptake (e.g., 8.8-151 mg kg−1 in shoots in 0.8 mg As L−1 treatment), translocation factor (2.1-47% in 0.8 mg As L−1) and tolerance (29-106% in 0.8 mg As L−1). Wetland plants with higher rates of ROL and root porosity tended to form more Fe/Mn plaque, possess higher As tolerance, higher concentrations of As on root surfaces and a lower As translocation factor so decreasing As toxicity. 相似文献
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Cadmium accumulation in and tolerance of rice (Oryza sativa L.) varieties with different rates of radial oxygen loss 总被引:1,自引:0,他引:1
Wang MY Chen AK Wong MH Qiu RL Cheng H Ye ZH 《Environmental pollution (Barking, Essex : 1987)》2011,159(6):1730-1736
Cadmium (Cd) uptake and tolerance were investigated among 20 rice cultivars based on a field experiment (1.2 mg Cd kg−1 in soil) and a soil pot trial (control, 100 mg Cd kg−1), and rates of radial oxygen loss (ROL) were measured under a deoxygenated solution. Significant differences were found among the cultivars in: (1) brown rice Cd concentrations (0.11-0.29 mg kg−1) in a field soil, (2) grain Cd tolerance (34-113%) and concentrations (2.1-6.5 mg kg−1) in a pot trial, and (3) rates of ROL (15-31 mmol O2 kg−1 root d.w. h−1). Target hazard quotients were calculated for the field experiment to assess potential Cd risk. Significant negative relationships were found between rates of ROL and concentrations of Cd in brown rice or straw under field and greenhouse conditions, indicating that rice cultivars with higher rates of ROL had higher capacities for limiting the transfer of Cd to rice and straw. 相似文献
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A field survey was conducted to identify potential Zn accumulators from an artisanal Zn smelting area in southwest China’s Guizhou Province. Hydroponic and soil culture experiments were performed to investigate the accumulation ability of Zn in Corydalis davidii. Zn concentrations in roots, stems and leaves of C. davidii in the smelting site were 1.1-3.5, 1.2-11.2, and 3.3-14 mg g−1, respectively, whereas Zn concentrations in roots, stems and leaves of C. davidii in the contaminated site impacted by the Zn smelting were 1.0-2.4, 1.9-6.5, and 3.0-1.1 mg g−1, respectively. Zn concentrations in leaves and stems of C. davidii were observed at above 10 mg g−1 that refers to the threshold of Zn hyperaccumulator. The concentration distribution of Zn in C. davidii was leaf > stem > root, and the Zn bioaccumulation factors of C. davidii were above 1. It is concluded that C. davidii has high tolerance to concentrate Zn stress, and that C. davidii is a newly discovered Zn-hyperaccumulator with high biomass in the aboveground parts. Based on the cultivation experiments, C. davidii could reduce Zn concentration by 26.6, 21.2, and 10.2 mg kg−1yr−1 by phytoextraction from the smelting slag, Zn-contaminated soil, and background soil, respectively. 相似文献
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