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Evaluation of Pb Phytoremediation Potential in Buddleja asiatica and B. paniculata 全文
2008
Waranusantigul, Piyaporn | Kruatrachue, Maleeya | Pokethitiyook, Prayad | Auesukaree, Choowong
The phytoremediation potential for Pb of Buddleja asiatica (a wild species) and a closely related cultivated species, B. paniculata, was investigated by means of field survey, hydroponic and pot experiments, and field trial experiments. Field surveys showed that B. asiatica had an extraordinary accumulation capacity and tolerance for Pb. Plants grown in soil with 2,369.8-206,152 mg kg⁻¹ total Pb accumulated 1,835.5-4,335.8 mg kg⁻¹ Pb in their shoots. Under hydroponic conditions (10, 20 mg l⁻¹ Pb), both B. asiatica and B. paniculata showed unusually high concentrations of Pb in their roots (12,133-21,667 mg kg⁻¹) and increased biomass production. A pot experiment in a greenhouse without any soil amendments was conducted on three different soils with various Pb contents (10,652, 31,304, 89,083 mg kg⁻¹) for 3 months. The results showed that both species of Buddleja had an increase in the biomass similar to the control plants. There was a slight decrease in survival rates of plants grown in soil with 89,083 mg kg⁻¹ Pb content. A field trial experiment was conducted for 6 months at three sites around the Pb mine area in which plants were provided with Osmocote fertilizer. Both Buddleja species showed 100% survival, increased biomass production and phytoextraction capacity (TF 1.1-2.3) when grown in soil with Pb content of 94,584-101,405 mg kg⁻¹. Plants accumulated 2,273-3,675 mg kg⁻¹ Pb in their shoots. The results suggest these Buddleja plants are suitable for use in the phytoremediation of Pb-contaminated soil.
显示更多 [+] 显示较少 [-]Phytoremediation of Mercury and Arsenic from Tropical Opencast Coalmine Effluent Through Naturally Occurring Aquatic Macrophytes 全文
2008
Miśra, Vīrendra Kumāra | Upadhyay, Alka Rani | Pathak, Vinita | Tripathi, B. D.
Under the present investigation phytoremediation of mercury and arsenic from a tropical open cast coalmine effluent was performed. Three aquatic macrophytes Eichhornia crassipes, Lemna minor and Spirodela polyrrhiza removed appreciable amount of mercury and arsenic during 21 days experiment. Removal capacities of these macrophytes were found in the order of E. crassipes > L. minor > S. polyrrhiza. Translocation factor (shot to root ratio of heavy metals) revealed low transportation of metals from root to leaves leading higher accumulation of metals in root as compared to leaves of the plant. It was evident from plant tissue analysis that mercury and arsenic up take by macrophytes had deteriorated the N, P, K, chlorophyll and protein content in these macrophytes. Correlations between removal of arsenic and mercury from mining effluent and its increase in plant parts were highly significant. Results favoured selected species to use as promising accumulator of metals.
显示更多 [+] 显示较少 [-]Changes in Fatty Acid Composition and Content of Two Plants (Lolium perenne and Trifolium repens) Grown During 6 and 18 Months in a Metal (Pb, Cd, Zn) Contaminated Field 全文
2008
Bidar, G. | Verdin, A. | Garçon, G. | Pruvot, C. | Laruelle, F. | Grandmougin-Ferjani, A. | Douay, F. | Shirali, P.
The aim of this in situ study was to investigate the fatty acid (FA) composition and content in roots and shoots of Lolium perenne and Trifolium repens, grown under heavy metal stress (Cd, Pb, Zn). The composition of FA was quite similar for the two plants and the two organs; main FA were palmitic acid (C16:0), oleic acid (C18:1), linoleic acid (C18:2) and linolenic acid (C18:3). For both plants, the major FA that characterized the roots was C18:2 whereas C18:3 was the prominent FA in shoots. For the first sampling (S1), in the roots of L. perenne and T. repens, polyunsaturated fatty acids (PUFA) were affected by metal contamination while, in the second sampling (S2), PUFA were affected in the shoots of the two plants. This alteration of PUFA was well correlated with the bioaccumulation factor of metals which decreased in roots and increased in shoots with the time. Moreover, a positive correlation was found between the PUFA decrease and the malondialdehyde (MDA) content, indicating the occurrence of a lipid peroxidation induced by the metal stress.
显示更多 [+] 显示较少 [-]Utilization Potential of Peats - a Study on Peat Biodegradability Determined by Respirometric Method 全文
2008
Roppola, Katri | Kuokkanen, Toivo | Kujala, Kauko | Kuokkanen, Matti
The biodegradation of different peat types was studied with a manometric respirometric test. Compaction peat and sphagnum peat samples were analysed, and the effect of peat pH on biodegradation behaviour was evaluated. Only minor (BOD/ThOD < 0.4%) biodegradation was observed with compaction peat samples, and the stable state, in which biodegradation stopped, was achieved during a two month period. As expected, sphagnum peat samples with a lower decomposition rate degraded more than compaction peat samples. Alkalinity (pH between ca. 4-9) of the peat was noticed to reduce the degree of biodegradation and accelerate the achievement of the stable state.
显示更多 [+] 显示较少 [-]Increasing the Knowledge of Heavy Metal Contents and Sources in Agricultural Soils of the European Mediterranean Region 全文
2008
Peris, M. | Recatalá, L. | Micó, C. | Sánchez, R. | Sánchez, J.
This paper contributes to increase the knowledge of the contents and sources of heavy metals (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn) to agricultural soils in Castellón province (Spain), a representative area of the European Mediterranean region. The surface horizons of 77 agricultural soils under vegetable crops were sampled and heavy metals were analysed by atomic absorption spectroscopy (AAS) after microwave extraction using the USEPA 3051A method. Mean heavy metal contents were similar to those obtained in other areas of this region. However, heavy metal contents (e.g. Cr, Pb) in some soils were above the maximum limit set in the 86/278/CEE Directive. Multivariate analysis (correlation analysis and principal component analysis - PCA) was performed so as to identify the sources of heavy metals to soils. Co, Fe and Ni were highly correlated amongst them (r > 0.800; p < 0.01), whereas Cr and Mn were less correlated with Co, Fe and Ni (r > 0.500; p < 0.01). Other relationships among heavy metals (i.e. Cu, Pb and Zn) were also identified, although correlation coefficients were not so high as those among Co, Fe and Ni (r < 0.500; p < 0.01). Contents of Co, Fe, Mn and Ni were interpreted to be mainly associated with parent rocks corresponding to the first principal component (PC1). On the other hand, Cd, Cu, Pb and Zn were interpreted to be mainly related to anthropogenic activities and comprised the second (Pb and Zn) and the third (Cd and Cu) principal components (PC2 and PC3, respectively), designated as anthropogenic components. Remarkably, Cr appears to be related in the study area to both the lithogenic and the anthropogenic components. Lithogenic elements were highly correlated with soil properties. Positive relationships with CEC (r > 0.200; p < 0.05) and clay (r > 0.400; p < 0.01), and negative relationships with carbonates (r > -0.400; p < 0.01) and sand (r > -0.300; p < 0.01) were observed. Anthropogenic elements were less correlated with soils properties, since these elements are generally more mobile because they form more soluble chemical species associated to anthropogenic sources. Particularly, no correlation was found between Cd and Zn and soil properties. These findings extend results achieved in other parts of the region, highlighting the need to set soil quality standards in order to declare soils affected by anthropogenic pollution, particularly in the case of anthropogenic metals such as Cd, Cu and Pb, and also Cr and Zn in some areas. Further knowledge from other areas in this region would improve the basis for proposing such standards at regional level, which is a priority objective in Europe according to the European Thematic Strategy for Soil Protection.
显示更多 [+] 显示较少 [-]Impacts of Pollution from Different Sources on Ecological Quality of a Multiple-use Coast 全文
2008
Wu, Jianyong | Wang, Jinhui
Investigation of pollution sources and their impacts on ecosystems is important, not only for better understanding the responses of an ecosystem to pollutants, but also for making practicable prevention and control plans. In this study, ecological quality of three areas which received different source pollutants in Shanghai coast were evaluated and compared in four seasons using Shannon-Wiener index (H'), a benthic diversity index as an indicator of ecological quality of coastal waters. The genotoxicity and physical-chemical variables of water samples were also analyzed. The H' value indicated the ecological quality of Shanghai coastal waters was seriously impacted, and the ecological quality of two areas receiving waste discharges were significantly worse than that of the natural protection zone but not significantly different in four seasons. The positive genotoxic response was detected in most samples from two discharge zones but not detected in the samples from the natural protection zone. However, no significant difference was observed in water quality variables in the different coastal areas. Our study suggested that the point source pollution had significantly contributed to the genotoxicity of the coastal waters and impaired benthic assemblages, while the deterioration of ecological quality status was also critically impacted by the stressors from other sources.
显示更多 [+] 显示较少 [-]Trace metals (Cu, Mn, Ni, Zn, Fe) Contamination in Marine Sediment and Zooplankton Samples from Izmir Bay. (Aegean Sea, Turkey) 全文
2008
Kontas, Aynur
Metal (Cu, Mn, Ni, Zn, Fe) concentrations in marine sediment and zooplankton were investigated in Izmir Bay of the Eastern Aegean Sea, Turkey. The study aimed to assess the levels of metal in different environmental compartments of the Izmir Bay. Metal concentrations in the sediment (dry weight) ranged between 4.26-70.8 μg g-¹ for Cu, 233-923 μg g-¹ for Mn, 14.9-127 μg g-¹ for Ni, 25.6-295 μg g-¹ for Zn, 12,404-76,899 μg g-¹ for Fe and 38,226-91,532 μg g-¹ for Al in the Izmir Bay. Maximum metal concentrations in zooplankton were observed during summer season in the inner bay. Significant relationships existed between the concentrations of certain metals (Al, Fe, Mn and Ni) in sediment, suggesting similar sources and/or similar geochemical processes controlling such metals. Higher concentrations of Cu, Zn and percent organic matter contents were found in the middle-inner bays sediments. Based on the correlation matrix obtained for metal data, organic matter was found to be the dominant factor controlling Cu and Zn distributions in the sediment. In general, mean Cu and Zn levels in the bay were above background concentrations in Mediterranean sediments. Zooplankton metal concentrations were similar to sediment distributions.
显示更多 [+] 显示较少 [-]Decomposition of Zn-rich Arabidopsis halleri Litter in Low and High Metal Soil in the Presence and Absence of EDTA 全文
2008
Chander, Krishan | Joergensen, Rainer Georg
Hyperaccumulating plants are increasingly investigated in combination with EDTA addition to soil for phytoremediation of heavy metal contaminated soils. A 60-day incubation experiment was carried out to investigate the effects of heavy metal release during the decomposition of Zn-rich (15.7 mg g-¹ dry weight) Arabidopsis halleri litter on C mineralization, microbial biomass C, biomass N, ATP, and adenylate energy charge (AEC). These effects were investigated in two soils with different Zn, Cu, and Pb levels, with and without EDTA addition to soil. The sole addition of Zn-rich A. halleri litter to the two soils did not increase the contents of NH₄NO₃ extractable Zn, only with the combined additions of EDTA and litter was there a considerable increase, being equivalent to three times the added amount in the low metal soil and to 50% in the high metal soil. Litter amendment increased the CO₂ evolved; being equivalent to 44% of the added C in the two soils, but EDTA addition had no significant effect on CO₂ evolution. Litter amendment resulted also in an 18% increase in microbial biomass C, 27% increase in ATP and 6% increase in AEC in the two soils, but EDTA had again no effect on these indices at both metal levels. In contrast, the sole addition of litter had no effect on microbial biomass N, but EDTA addition increased microbial biomass N on average by 49%. The application of EDTA for chelate-assisted phytoextraction should in the future consider the risk of groundwater pollution, which is intensified by resistance of EDTA to microbial decomposition.
显示更多 [+] 显示较少 [-]Mobility and Availability of Copper in Agricultural Soils Irrigated from Water Treated with Copper Sulfate Algaecide 全文
2008
Salam, D. | El-Fadel, M.
In this paper, downward movement and availability of copper in soils irrigated with CuSO₄ algaecide treated water were examined using column leaching experiments. Two simulations considering 1 and 10 years irrigation period were conducted at copper application rate of about 18.7 kg CuSO₄/ha/year. Effluent copper concentrations and vertical distribution of acid and DTPA-extractable copper in the soil columns were determined. Nearly 99% of the applied copper was retained in the soil with a C e/C ₀ values on the order of 10⁻³. Retention profiles showed that copper was retained in the upper 2 to 3 cm of the soil. However, a significant fraction of the retained copper was detected in available form (DTPA-Cu) suggesting that plants toxicity could be a major limitation for the use of CuSO₄ treatment in irrigation water.
显示更多 [+] 显示较少 [-]PM10, O₃, CO Concentrations and Elemental Analysis of Airborne Particles in a School Building 全文
2008
Triantafyllou, A. G | Zoras, S | Evagelopoulos, V | Garas, S
Measurements of indoor and outdoor PM10, as well as indoor O₃ and CO concentrations were conducted and are presented here. These measurements were carried out at an institute building, located in a suburban industrial area in Greece. Both indoor and outdoor PM10 samples were also collected and their elemental composition was identified by ED-XRF analysis. Twenty seven major, minor and trace elements were identified. The measurements took place generally in different periods of institute operation, from June 2004 to February 2005. The indoor PM10 concentrations which were measured during the normal operation period of the institute were found to be many times higher than the respective outdoor PM10 concentrations of the same periods. On the contrary, the indoor PM10 concentrations which were measured during the holiday period were found to be lower than their corresponding outdoor values. Indoor O₃ and CO concentrations were found to be in low level. Indoor PM10 concentrations were found to be in a relative good correlation with O₃ (r = 0.45) and in high correlation (r = 0.98) with CO concentrations. On average, total elements concentrations were much higher indoors relative to outdoors. Based on above findings we attempted to determine the pollution sources of the indoor environment and to investigate some parameters or chemical processes that affect indoor pollutants' levels.
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