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961.
Effects of 5-year application of municipal solid waste compost on the distribution and mobility of heavy metals in a Tunisian calcareous soil 总被引:2,自引:0,他引:2
Walid Ben Achiba Noureddine Gabteni Abdelbasset Lakhdar Gijs Du Laing Marc Verloo Naceur Jedidi Tahar Gallali 《Agriculture, ecosystems & environment》2009,130(3-4):156-163
It is obvious that the application of solid waste compost improves the soil fertility. These wastes, however, may also have some negative effects on the agricultural environment due to their metal content. This research aimed at evaluating the influence of Tunisian municipal solid waste compost and farmyard manure on some chemical properties and the distribution of heavy metals in a calcareous Tunisian soil (clayey–loamy soil). A field plot experiment, without vegetation, was installed since 1999 at the experimental farm of the Agronomic National Institute of Tunis (INAT) in the region of Mornag (20 km south of Tunis, Tunisia). During 5 years, the field received yearly the following treatments: 0, 40, 80 and 120 t/ha of municipal solid waste compost and 0, 40 and 120 t/ha of manure. The fractionation of heavy metals in the soil was evaluated after 5 years using a sequential extraction procedure. The application of the two amendments was found to increase the content of organic matter, the total nitrogen content and the electrical conductivity, whereas it slightly decreased the soil pH. The addition of manure did not have a significant effect on the accumulation of heavy metals in the soil, whereas compost application increased the total concentration of heavy metals in the soil. The distribution of heavy metals between the different fractions in untreated and treated soils showed the residual fraction to be dominant, followed by the fraction bound to Fe and Mn oxides. The amount of Cu bound to the organic fraction increased with the application rate, which is probably caused by the formation of organic complexes. For the other metals, the increase of the association with organic matter is very limited. The application of compost moreover increases the amount of Zn associated with Fe and Mn oxides. The “Mobility Factor (MF)” was quite low and did not change after the 5-year application of the two organic amendments. It always remained lower than 10%, although for Cd it amounted to 17%. 相似文献
962.
HAN Dechang ZHANG Xiaoke TOMAR Vijay Vikram Singh LI Qi WEN Dazhong LIANG Wenju 《环境科学学报(英文版)》2009,21(2):193-198
Soil samples were collected with distance at 5, 20, 40, 80, 160 and 320 m from the Shen-Ha Highway, Northeast China, to investigate the effect of heavy metals of highway origin on soil nematode guilds. The contents of soil Pb, Cu and Zn and the nematode community structure in this investigation were analyzed. The results showed that the contents of total and available Pb, Cu and Zn varied significantly with the different distances from the highway. Pb was the main pollutant in the soils in the vicinity of Shen-Ha Highway and the zone from 20 to 40 m away from the highway was the most polluted area. The highest abundance of soil nematodes was found at 5 m while the lowest at 20 m away from the highway. Thirty six genera of nematodes belonging to 23 families were identified. Nematode guilds having different responses to soil heavy metals were classified into four types. Soil nematode guilds may act as a prominent indicator to heavy metal pollution of highway origin. 相似文献
963.
The 25 road-deposited sediments were collected from five di erent land-use zones (industrial, residential, commercial, park, and
countryside) in Hangzhou, China. The concentrations of metals (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) in these samples were
determined using ICP-AES after digestion with the mixture of HNO3-HF-HCl (aqua regia), and chemically fractionated according
to the modified BCR (the European Community Bureau of Reference) sequential extraction procedure. The high metal concentration
levels were detected in the sample from industrial zone and commercial zone having heavy tra c. While the low metal levels were
noted in the street dust sample from residential zone, park, and countryside zone. The mobility sequence based on the sum of the
BCR sequential extraction stages was: Zn (80.28%), Pb (78.68%), Cd (77.66%) > Cu (73.34%) > Mn (67.92%) > Co (41.66%) >
Ni (30.36%) > Cr (21.56%), Fe (20.86%). Correlation analysis and principal component analysis were applied to the data matrix to
evaluate the analytical results and to identify the possible pollution sources of metals. Factor analysis showed that these areas were
mainly contaminated by three sources, namely lithology, tra c, and industry. 相似文献
964.
淇澳岛红树林生态系统中重金属含量相关性 总被引:3,自引:1,他引:2
采集珠海淇澳岛北部大围湾的红树林区潮间带沉积物和植物组织样品若干,测定各样品中Cu、Zn、Cd和Pb的含量,四种重金属含量在各沉积物中、各植物组织中以及沉积物和植物组织之间的相关性。研究表明,沉积物中Pb和Zn含量呈极强正相关,Pb、Zn与Cd含量之间呈强正相关,其他各类重金属之间的相关性不显著。四种重金属与沉积物颗粒形态相关性均不显著。红树植物各组织对四种重金属的富集系数范围为0.001~0.72,0.006~0.39,0.053~1.97和0.004~0.24,富集能力与林龄正相关,其中对Zn、Cd和Pb的富集系数与土壤中含量呈负相关,表明在过高重金属污染胁迫的环境中红树植物有自行降低富集能力以避免被伤害的趋势。 相似文献
965.
966.
The concentrations of Cd, Cr, Cu, Ni, Pb, and Zn in two plant species (Scirpus tripueter Linn. and Cyperus malaccensis Lam.), water, and soils sampled from the reclaimed tidal riparian wetlands (RTRWs) and the natural riparian wetlands (NRWs) in the Pearl River estuary (PRE), were analyzed to investigate and compare their distribution and accumulation. The results show that the concentrations of the six studied heavy metals in soils exceed the eco-toxic threshold recommended by USEPA. The concentrations of Cd, Cr, and Zn in plants may lead to toxic effects compared to others.The hydraulic conditions and the degree of human disturbances can affect the heavy metal accumulation in RTRWs and NRWs. The heavy metal concentrations in water are higher whereas they are lower in soils of RTRWs Compared with that in the NRWs. The accumulation of heavy metals in the roots of plants is higher in NRWs than those in RTRWs while the opposite result is found for heavy metal accumulation in shoots. Based on the bioaccumulation and translocation factors, the plants in NRWs have the higher capacity to accumulate heavy metals, while higher abilities to transport heavy metals from roots to shoots are observed in RTRWs. Heavy metal contaminations in RTRWs are dominated by anthropogenic sources from both side uplands and river water, whereas in NRWs, the metal accumulations are simultaneously affected by anthropogenic and natural factors. 相似文献
967.
968.
969.
2009年6月至2010年7月对闽江口及敖江口海域养殖缢蛏中的重金属(Cu,Hg,Pb,As,Cd)、有机污染物(TPH,DDTs,PCBs,HCHs)、麻痹性贝毒、腹泻性贝毒和微生物(大肠杆菌、沙门氏菌、单核细胞增生李斯特氏菌、细菌总数)指标进行检测。结果表明:闽江口及敖江口海域养殖缢蛏中的Cu、Pb、Cd、Hg、DDTs、HCHs、PCBs、DSP、PSP、沙门氏菌、单核细胞增生李斯特氏菌、大肠杆菌含量都符合食品卫生安全要求;部分海区缢蛏体内As、细菌总数的含量超标;部分缢蛏养殖区中的TPH超标严重。 相似文献
970.
酸缓冲容量对污泥屏障重金属再溶出控制研究 总被引:1,自引:0,他引:1
借助污泥中的厌氧微生物活动,污泥屏障可用来固定尾矿堆场的重金属.针对尾矿风化淋滤形成的酸性采矿废水(acidmine drainage,AMD)与污泥屏障相互作用,可能会引起已固定重金属再次溶出问题,通过酸滴定实验,研究了不同厌氧培养时间的污泥悬液的酸缓冲容量及其对重金属再溶出的影响.结果表明,污泥悬液酸缓冲容量与悬液固液比成正比,并随着厌氧还原程度的加深而增加.碳酸盐缓冲体系和有机质缓冲体系对污泥悬液酸缓冲有重要意义.酸滴定实验发现,随着pH降至6.2以下,重金属Zn、Pb和Cu开始快速溶解释放,且释放量符合ZnCuPb.基于实验结果,建立了污泥屏障在AMD渗透条件下酸缓冲容量消耗的数学模型.模拟计算结果表明,对于厚度2.0 m的污泥屏障,即使在10.0 m水头的AMD渗透酸化条件下,有效酸缓冲容量经历666 a之后才能被耗尽,在此时间内污泥屏障具备对重金属的生物化学固定能力. 相似文献