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1.

Purpose

Coal-fuelled power plants can discharge hazardous materials, particularly heavy metals such as lead (Pb). An alternative way of reducing Pb concentration from contaminated sediments is through phytoremediation. Presently, there are few research findings on the phytoremediation potential of mangroves on metals like Pb. The study was conducted to survey and identify mangroves that thrive near the coal-fired power plant and to assess the phytoremediation potential of mangroves on Pb in sediment.

Materials and methods

The study sites were located in the mangrove ecosystems of Sitio Oyon and Sitio Asinan in Masinloc, Zambales, Philippines. The first stage of our study was to survey and identify the mangrove species. The second stage was to assess the levels of Pb in the sediments, water, and tissues of mangrove trees. The diversity assessment of the mangrove species was done through the use of 10?×?12 m quadrat technique. Water and sediment samples from each mangrove ecosystem were collected using composite sampling methods.

Results and discussion

Three mangrove species were identified in the study sites: Avicennia marina, Rhizophora stylosa, and Sonneratia alba. The order of importance of the mangrove trees in the two sampling locations, based on an importance value index (IVI), were as follows: SA (IVI?=?171.20)?>?AM (77.79)?>?RS (51.01). The total uptake of Pb from sediments near the power plants varied significantly (p?≤?0.001) among the three mangrove species. S. alba had the highest Pb uptake of 48.4 kg ha?1 followed by A. marina (23.1 kg ha?1), and R. stylosa (2.4 kg ha?1). These three mangrove species have the potential to phytoremediate Pb in the sediment.

Conclusions

The three mangrove species present in the coastal ecosystem near the electric power plant—A. marina, R. stylosa, and S. alba—were potential phytoremediators of sediment Pb. The present study indicated that the mangroves possess beneficial characteristics that remove Pb from contaminated sediments in areas directly affected by coal-fired power plants, and thus have potential phytoremediation properties.  相似文献   

2.
通过盆栽试验,研究了Pb及Pb-Cd复合污染土壤添加EDTA(乙二胺四乙酸)对小藜生长和转运、富集Pb、Cd的影响。结果表明,高浓度的EDTA对小藜的生长有抑制作用,Pb及Pb-Cd复合处理下EDTA最佳添加浓度均为2.5 mmol·kg^-1,此时小藜对Pb的转运系数达2.66和2.41,富集系数达1.51和1.82,分别比对照提高554%和493%、8 431%和2 367%;对Cd的转运系数达1.87和3.47,富集系数达1.78和10.8,分别比对照提高165%和355%、77%和283%。2.5 mmol·kg^-1EDTA辅助小藜修复Pb-Cd复合污染土壤的效果优于修复Pb污染土壤的效果。  相似文献   

3.
Petroleum contamination poses a significant threat to environmental ecosystems world-wide. Phytoremediation can be used to enhance degradation of petroleum contaminants in soil. However, selection of plants for phytoremediation has proven to be complicated. This research examines the heritability of the alfalfa cultivar Riley for phytoremediation based on parental total petroleum hydrocarbon (TPH) degradation after twelve months of growth. Traits other than degradation potential, such as root and shoot yield, height, and maturity, were examined for use as selection traits. Riley showed moderate to low heritability that suggests the possibility of breeding for phytoremediation efficiency. In addition, root and shoot yield were found to correlate to TPH degradation. Crosses in which the female parent was typically associated with low TPH dissipation yielded progeny that were high efficiency TPH degraders.  相似文献   

4.
Soils polluted by heavy metals can be reclaimed using a number of expensive tactics that either remove the contaminants or stabilize them within the soil. The value of metal accumulating plants for environmental remediation has recently been appreciated and promising results have been obtained. This paper reports a study on the behavior of Brassica napus, Brassica juncea, Raphanus sativus and Brassica carinata grown on a substrate contaminated by several heavy metals caused by the use of contaminated irrigation water. Data on carbon dioxide assimilation, biomass growth and the bioconcentration and translocation factor of each metal in each species were measured. The polluted substrate caused only a small variation in photosynthesis, however transpiration was more affected by the experimental substrate and in all three species of the genus Brassica the presence of metals in the substrate resulted in higher transpiration levels.Two bioconcentration factors were calculated respectively for the roots (BCF) and the shoots (BCF); the BCF was >1 for all the species for Cd, Cu, Ni and Zn without significant differences among species. All the values of BCF were lower than 0.5; among the metals, all Brassica species demonstrated a similar performance for Cd and Zn, whereas for other elements the bioconcentration factor was very low.  相似文献   

5.
蚯蚓对印度芥菜修复Zn、Pb污染土壤的影响   总被引:4,自引:0,他引:4  
以褐土为供试土壤,分别加入不同浓度梯度Zn2+(0,100,200,400 mg kg-1)或Pb2+(0,200,400,800 mg kg-1)模拟土壤污染,设置添加蚯蚓与不添加蚯蚓处理,通过盆栽实验,研究蚯蚓对印度芥菜生长量和重金属吸收量的影响,旨在探讨蚯蚓在植物-土壤系统中影响重金属迁移转化的作用机理,为蚯蚓在植物修复技术的实践与完善提供理论参考。结果表明:(1)在Zn、Pb污染土壤中,蚯蚓生长率分别降低3%~24%、6%~29%;(2)蚯蚓活动可以降低土壤的pH,显著增加土壤中Zn的有效态含量;(3)蚯蚓活动显著增加了印度芥菜地上部生物量(22.6%~88.6%鲜重,31.3%~122%干重)和印度芥菜地上部Zn的浓度及Zn和Pb的吸收量。印度芥菜地上部重金属浓度和吸收量与土壤中DTPA提取态含量呈极显著正相关(P <0.01),与土壤pH呈负相关。(4)蚯蚓对重金属的活化和对植物生长的促进是解决植物修复瓶颈问题的有效手段。  相似文献   

6.
Long-term use of sewage water for irrigation enhances the accumulation of trace elements in the soil and may contribute to contamination in low-lying areas. Therefore, this study investigated the extent of pollution introduced by Pb, Cd, Zn and B to the sandy soils of Abu Rawash and El-Gabal El-Asfar areas, Egypt, which have been irrigated with sewage water for up to 67 yr. Results revealed that prolonging the periods of irrigation was associated with significant increases in the total and available forms of Pb, Cd, Zn and B. These elements tended to accumulate in the surface layers, with the exception of B which increased at lower depths. The relative percentage of the available to total element forms reflected the low solubility and availability of both Pb and B compared with Cd and Zn. However, in all cases, the concentrations of these elements have not accumulated to toxic levels after 67 yr of sewage irrigation. Nevertheless, care and good management should be considered in the future with continuous use of sewage water for irrigation.  相似文献   

7.
蚯蚓在植物修复重金属污染土壤中的应用前景   总被引:24,自引:1,他引:24  
重金属污染土壤的植物修复技术是绿色生物技术,该技术的应用受制于两个主要因素:超积累植物生物量小和土壤中重金属有效性低。本文在收集大量资料基础上,论述了蚯蚓与重金属的相互关系:重金属对蚯蚓的毒理效应和蚯蚓对重金属的忍耐力。根据在重金属污染土壤中,蚯蚓活动能提高植物生物量和土壤中的重金属的生物有效性,论证了在重金属污染土壤植物修复技术中引入蚯蚓的可行性,并指出引入蚯蚓的植物修复技术当前的研究热点及今后的研究方向。  相似文献   

8.
Here we present results of a survey conducted to identify and characterize spontaneously growing arsenic-tolerant plant species of the area around the old arsenic/gold mine in ZlotyStok (Poland), with respect of their potential use in phytoremediation. Plants and soil from their rhizosphere were sampled and analyzed for concentrations of As and accompanying Mn, Fe, Mg, Ca, Al, Cu, Zn, Ba, Pb, Ni, Cs, V, Cr, Sr, Rb, Bi, Mo and U. The soil contained primarily very high As, Pb and Al concentrations (up to 7,451, 1,058 and 31,272 mg/kg respectively). The ability of identified species to modify the amount of bioavailable arsenic in their rhizosphere was determined by single extractions of soil samples with the use of water, phosphate buffer, EDTA, and acetic acid. Although As-hyperaccumulators were not found, Calamagrostis arundinaca was identified as a new species which successfully carried out the natural phytoextraction of arsenic. This plant was able to increase substantially the arsenic availability in the soil, and likely due to efficient uptake decreased the total As concentration within the root zone by around 40% relative to the reference soil. Thus, it has high potential for phytoremediation. The lowest amount of available arsenic was found in the rhizosphere of Stachys sylvatica, the species with the lowest As shoot concentration (compared with other plant species). It was proposed as a good candidate for phytostabilization.  相似文献   

9.
Salvinia minima combines several advantages for being used in aquatic phytoremediation. The objectives of this work were to compare the growth kinetics and productivity of S. minima and Spirodela polyrrhiza in high-strength synthetic organic wastewater (HSWW) and to evaluate the growth characteristics of S. minima in various culture media, including anaerobic effluents from pig wastewater (PWAE). It was found that the Relative Growth Rate (RGR) of S. minima was significantly higher (p?<?0.05) compared to the RGR of S. polyrrhiza in Hutner Medium (HM) and in HSWW. Also, S. minima showed a 1.5 fold productivity and a 2.3 fold productivity, compared to S. polyrrhiza in HM and HSWW, respectively. Diauxic growth of S. minima was observed preferentially under pH control and there was a simultaneous consumption of two nitrogen sources. Productivity of S. minima was similar in pig waste anaerobic effluents (PWAE) and in HM without ammonium nitrate and amended with ammonium sulphate (MHM?+?AS), at an initial NH4 concentration of 35 mg l?1. Above this level, the productivity was found to decrease as the initial ammonium concentration increased, in both media. Growth was completely inhibited at 140 mg l?1 in the PWAE. In summary, S. minima is a better option than S. polyrrhiza for treating high-strength organic wastewater and lagoons should be operated at a maximum initial ammonium–nitrogen concentration of 70 mg l?1 and at a pH of 5.0 or 6.0. Likewise, the initial density should be maintained in the range of 7 to 15 g dw m?2.  相似文献   

10.
We introduced the human cytochrome P450 gene CYP2B6 into rice plants (Oryza sativa L. cv. Nipponbare), and the CYP2B6-expressing rice plants became more tolerant to various herbicides than nontransgenic Nipponbare rice plants. In particular, CYP2B6 rice plants grown in soil showed tolerance to the chloroacetanilide herbicides alachlor and metolachlor. We evaluated the degradation of metolachlor by CYP2B6 rice plants to confirm the metabolic activity of the introduced CYP2B6. Although both CYP2B6 and nontransgenic Nipponbare rice plants could decrease the amount of metolachlor in plant tissue and culture medium, CYP2B6 rice plants could remove much greater amounts. In a greenhouse, the ability of CYP2B6 rice plants to remove metolachlor was confirmed in large-scale experiments, in which these plants appeared able to decrease residual quantities of metolachlor in water and soil.  相似文献   

11.
12.
Heavy metal phytoextraction is a soil remediation technique, which makes use of plants in removing contamination from soil. The plants must thus be tolerant to heavy metals, adaptable to soil and climate characteristics, and able to take up large amounts of heavy metals. Most of the high biomass productive plants such as, maize, oat and sunflower are plants, which do not grow in cold climates or need intensive care. In this study three “weed” plants, Borago officinalis; Sinapis alba L. and Phacelia boratus were investigated for their ability to tolerate and accumulate high amounts of Cd and Pb. Pot experiments were performed with soil containing Cd and Pb at concentrations of up to 180 mg kg?1 and 2,400 mg kg?1 respectively. All three plants showed high levels of tolerance. Borago officinalis; and Sinapis alba L. accumulated 109 mg kg?1 and 123 mg kg?1 Cd, respectively at the highest Cd spiked soil concentration. Phacelia boratus reached a Cd concentration of 42 mg kg?1 at a Cd soil concentration of 100 mg kg?1. In the case of Pb, B. officinalis and S. alba L. displayed Pb concentrations of 25 mg kg?1 and 29 mg kg?1, respectively at the highest Pb spiked soil concentration. Although the Pb uptake in P. boratus reached up to 57 mg kg?1 at a Pb spiked soil concentration of 1,200 mg kg?1, it is not suitable for phytoextraction because of its too low biomass.  相似文献   

13.
14.
Cyt b基因在进化过程中受到的选择压力较小,具有较快的进化速率,加上容易使用一些通用引物进行扩增和测序,非常适合进行种间系统进化的分析,近年来被广泛应用于鱼类的系统分化和分子分类的研究。月鳢和斑鳢均属鲈形目,鳢科鱼类,是我国南方名贵的水产养殖品种,有着类似的形态特征和相似的生活习性,在生产上人们常将它们统称为乌鱼。在分类上曾将月鳢和斑鳢分属在不同的属,月鳢为月鳢属(Channa),斑鳢为鳢属(Ophiocephalus)。为了从分子水平研究这两种鱼的亲缘关系,本研究测定了月鳢和斑鳢线粒体Cyt b全基因测序,并进行了比较和分析。  相似文献   

15.
河北省气候生产潜力的估算与区划   总被引:4,自引:0,他引:4  
利用河北省99个气象站点1965-2005年逐年年平均气温、年降水量资料,应用Miami模型、Thornthwaite Memo-riai模型估算了河北省温度气候生产潜力(TSPt)、降水气候生产潜力(TSPN)和蒸散量气候生产潜力(TSPV)。结果表明:河北省各地热量条件较好,水分是限制作物产量的主要因素;平原中南部地区为TSPt的高值区,燕山南麓为TSPN的高值区,TSPV的高值区分布较复杂,主要集中在燕山南麓,TSPN、TSPN、TSPV的低值区均位于坝上高原;根据TSPV值,采用经验正交函数分解(EOF)和旋转经验正交函数分解(REOF)方法进行气候区划,将河北省划分为5个区域,分别为冀西北高原、冀北山地、燕山南麓、冀中平原和冀南平原,各区特点明显,可为当地的农业生产布局提供参考。  相似文献   

16.
The objective of this study was to compare six soil tests (1 M KNO3, 1 M NH4OAC, 0.005 M DTPA, 0.1 M EDTA, 1 M HNO3 and 0.025 M Ca DTPA B4O7) as extractants for soil Pb and as predictors of plant available Pb for wheat (Triticum aestivum L.) in the greenhouse. The soils recieved 0, 200 and 400 mg Pb kg?1 as Pb(NO3)2 and are referred to as Pb0, Pb1 and Pb2 treatments respectively. Of the six soil extractants, 1 M HNO3 was the most effective extractant for Pb from Pb0 treatment whereas 0.1 M EDTA and 0.025 M Ca DTPA-B4O7 were the best and equally effective in their ability to extract Pb from Pb1 and Pb2 treatments. Regression analysis was used to develop two variable models for predicting Pb uptake by wheat as a function of extractable Pb and selected soil properties. The 0.025 M Ca DTPA-B4O7 extractant was the best in predicting uptake by wheat in Pb0 (r = 0.791*** significant at p = 0.001) and Pb1 (r = 0.726***) and Pb2 (r = 0.942***) treatments.  相似文献   

17.
18.
小麦SSR引物在冰草属植物分析应用中的评价   总被引:3,自引:0,他引:3  
冰草属(Agropyron Geartn.)又称冠状冰草复合群(crestedwheatgrass complex),是一个不超过10个种的小属。该属植物在农牧业生产中具有极其重要的价值,对这些物种的遗传多样性等研究,一直受到众多遗传学家和禾草学家的关注。在小麦野生近缘植物中,研究者以SSR作为有效技术进行了一些研究。对于冰草属植物,目前还没有有关的引物开发和应用的研究报道。本研究对小麦SSR引物在冰草属植物遗传分析中的可利用性进行了评价,以期为该类植物进一步的研究和利用提供借鉴。1材料和方法1.1材料实验材料(表1)为随机抽取的中国农业科学院作物科学研究…  相似文献   

19.
Phytoremediation is a helpful technique to remediate copper-contaminated areas. The aim of this study was to evaluate sunflower phytoremediation capacity in two vineyard copper-contaminated soils (Inceptisol and Mollisol) and a copper mining waste. Nutrient uptake, copper phytoaccumulation, translocation factor (TF), and bioaccumulation factor (BCF) of sunflower were evaluated after 57 days of growth. Plants grown in both the Mollisol and Inceptisol soils showed high plant height. Fresh biomass was high in the Mollisol in the shoots and roots and also demonstrated the highest values on the tolerance index (TI). The BCF after growth in all three of the copper contaminated soils as Inceptisol, Mollisol, and copper mining waste showed reduction of this index value to 0.19, 0.24, and 0.03, respectively against native soil (Mollisol under natural conditions (4.71). Sunflowers have some important characteristics such as high phytomass production, copper phytoaccumulation, and potential use to biofuel. Thus, sunflower is a potential candidate to phytoremediation of vineyard copper-contaminated soils.  相似文献   

20.
硼作为一种植物必需元素,在土壤中过量存在会对植物产生毒害,硼对植物的毒害作用以及利用植物修复高硼土壤已经日益受到关注。目前,硼对不同类型植物的毒害特点,植物的耐受机制还不十分清楚。特别是对于硼污染的植物修复,其研究还处于起步阶段。本文分别从植物的表观症状、生理生化和基因水平等层次,综述了过量硼对植物的毒害,并从高耐受性、超富集能力植物筛选,以及转基因技术应用等角度回顾了硼污染的植物修复研究进展。在此基础上,提出了当前相关研究存在的主要问题,并对未来的研究进行了展望。  相似文献   

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