Lead Contamination of the Roadside Ecosystem

Smith, William H.

doi:10.1080/00022470.1976.10470310

Cited by 117 publications

(28 citation statements)

References 43 publications

(49 reference statements)

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“…Pb oxychlorides were detected in dust particles emitted from a lead smelter (Sobanska et al, 1999;Wu, Biswas, 2000). Pb halides (chloride-bromides) as well as oxy-and hydroxyhalides were observed in automobile exhaust gases (Post, Buseck, 1985) and roadside soils (Smith, 1976). However, Pb oxyhalides have not only environmental importance and are also of interest from the viewpoint of material science as anisotropic materials with a variety of physical properties that depend strongly on the crystallographic direction.…”

Section: Introductionmentioning

confidence: 99%

Crystal chemistry of the mendipite-type system Pb₃O₂Cl₂—Pb₃O₂Br₂

Siidra¹,

Krivovichev²,

Armbruster³

et al. 2008

Zeitschrift Für Kristallographie - Crystalline Materials

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cations. The number of nonequivalent halogen sites is two (X1, X2). Short Pb--O bonds are located on one side of the Pb 2+ cations and weak Pb-X bonds are located on the other side of the Pb 2+ coordination sphere. The evident strong distortion of the Pb 2+ coordination polyhedra is due to the stereoactivity of the 6s 2 lone electron pairs of the Pb 2+ cations. Pb1-X2 and Pb2-X2 bonds are the most sensitive to the X site occupancy, which is in agreement with the non-linear behavior of the a and c parameters. Determination of unit-cell parameters by single crystal studies showed strong deviation from Vegard's rule. Nonlinearity of the lattice parameters is caused by selective ordering of the halide anions over X1 and X2 sites. Br atoms prefer the X2 position, whereas Cl prefers the X1 site. 2+ double chains to the large halide ions in the crystal structures of the mendipite series compounds.

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Section: Introductionmentioning

confidence: 99%

Crystal chemistry of the mendipite-type system Pb₃O₂Cl₂—Pb₃O₂Br₂

Siidra¹,

Krivovichev²,

Armbruster³

et al. 2008

Zeitschrift Für Kristallographie - Crystalline Materials

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“…While there has been some studies on the effects of industrially derived heavy metal pollution on leaf surface microorganisms (Gingell et al 1976, Bewley 1980, little work has been done on the effects of heavy metal and trace contaminants on leaf surface microorganisms in the roadside urban environment in general (Smith 1971, Smith 1976a, Smith 1976b, Smith 1977, Swailesh et al 2004) and on the effects of vehicular pollution on phylloplane microorganisms in particular (Mowll et al 1985) Therefore, a study to understand the impact of vehicular air pollution on the phylloplane microorganisms of roadside trees (Alnus nepalensis) was carried out.…”

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confidence: 99%

Influence of roadside pollution on the phylloplane microbial community of Alnus nepalensis (Betulaceae)

Joshi¹

2007

RBT

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Abstract:The North Eastern region of India is undergoing industrial development at a faster rate than expected. Roads form the main system of transportation and communication owing to the hilly topography of the region. Automobiles discharge a number of gaseous and trace metal contaminants. Human activities like stone grinding, road construction and sand milling also increase the atmospheric dust and heavy metal contaminant level. These contaminants get settled on leaf surfaces at roadsides and enter in contact with phylloplane microorganisms. This study compares microorganisms on leaf surfaces of alder (Alnus nepalensis (Betulaceae)) on roadside and non-roadside environments. Two sites dominated by alder were selected. One at a busy road intersection on the National Highway no. 44 in Shillong with high traffic density (8 000-9 000 heavy vehicles/day), taken as the polluted site and the other one in a forest approximately 500 m away from the roadside considered as the unpolluted site. Analysis of phylloplane microorganisms, lead, zinc, copper, cadmium and sulphur was carried out from leaves. The bacterial population was higher at the unpolluted site. Bacterial population showed a significant negative correlation with lead, zinc, copper, cadmium and sulphur. Similarly, fungal population was higher at the unpolluted site. A total of 29 fungal species were isolated from the phylloplane of A. nepalensis (polluted site 16 species; unpolluted site 28 species). Some fungal forms like Mortierella sp., Fusarium oxysporum and Aureobasidium pollulans were dominant in the polluted site. Numbers of phylloplane fungi and bacteria were significantly reduced in the polluted site. The correlation coefficient indicated a detrimental effect of metals like lead, zinc, copper, cadmium and sulphur on the microbial community of leaf surfaces. The specificity of certain fungi to the unpolluted site may be attributed to their sensitivity to pollution. The predominance of Aureobasidium pollulans, Fusarium oxysporum and Mortierella sp. in the polluted site may be due to their resistance to pollutants in roadside conditions. Rev. Biol. Trop. 56 (3): 1521-1529. Epub 2008 September 30.

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“…They gave 2 possible hypothesis for this positive relationship: (i) the application of different quantities of organic matter polluted with metals caused, over time, an increase in these elements in the soil, with the highest levels in soils treated with the largest amounts of organic matter, (ii) the metal content of the most polluted soils has interfered with C mineralisation, leading gradually to accumulation of organic C in these soils. Earlier studies have shown that the deposition of Pb from vehicle exhaust and fumes and abraded metals from vehicle components has resulted in metal contamination of roadside soils and vegetation (Lagerwerff and Specht, 1970;Smith, 1976;Harris, 1991). Post and Beeby (1996) studied rates of degradation of cellulose-strips and decomposition of litter bags in roadside soils of low and high metal concentrations.…”

Section: Organic Matter Decompositionmentioning

confidence: 99%

Effect of Metals Contamination on Soil Microbial Diversity, Enzymatic Activity, Organic Matter Decomposition and Nitrogen Mineralisation (A Review)

Khan¹

2000

Pakistan J. of Biological Sciences

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Soil is home to remarkable diversity of life from microbes to moles and a well-established ecosystem among these different organisms exists. Microorganisms either independently or in association with other organisms are playing very important role in the plant nutrients recycling. Soil metal concentrations above certain limits disrupt this ecosystem and as a result plant nutrient cycling process. Metal contamination in soils cause proportions of some groups of microorganisms to increase than the others. Compared with bacteria certain groups of fungi are less affected by soil metal pollution. Phospholipid fatty acid (PLFA) measurements in metal contaminated soils show that within bacterial population, metals are more toxic to gram-positive than gram-negative bacteria. Significant reductions in enzymatic activities occur in soils contaminated with metals and generally metals are more toxic to intra-cellular enzyme activities (e.g. dehydrogenase) than extra-cellular activities (e.g. phosphatase). Similarly, enzymes produced by bacteria are more affected by metal contamination than those produced by fungi. Organic matter decomposition and nitrogen mineralisation, which are carried out by various groups of microorganisms can also be affected by increased metal concentrations in the soils.

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Lead Contamination of the Roadside Ecosystem

Cited by 117 publications

References 43 publications

Crystal chemistry of the mendipite-type system Pb₃O₂Cl₂—Pb₃O₂Br₂

Crystal chemistry of the mendipite-type system Pb₃O₂Cl₂—Pb₃O₂Br₂

Influence of roadside pollution on the phylloplane microbial community of Alnus nepalensis (Betulaceae)

Effect of Metals Contamination on Soil Microbial Diversity, Enzymatic Activity, Organic Matter Decomposition and Nitrogen Mineralisation (A Review)

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Lead Contamination of the Roadside Ecosystem

Cited by 117 publications

References 43 publications

Crystal chemistry of the mendipite-type system Pb3O2Cl2—Pb3O2Br2

Crystal chemistry of the mendipite-type system Pb3O2Cl2—Pb3O2Br2

Influence of roadside pollution on the phylloplane microbial community of Alnus nepalensis (Betulaceae)

Effect of Metals Contamination on Soil Microbial Diversity, Enzymatic Activity, Organic Matter Decomposition and Nitrogen Mineralisation (A Review)

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Crystal chemistry of the mendipite-type system Pb₃O₂Cl₂—Pb₃O₂Br₂

Crystal chemistry of the mendipite-type system Pb₃O₂Cl₂—Pb₃O₂Br₂