The geographic distribution of metals in urban soils: the case of Syracuse,NY

A paucity of literature currently exists pertaining to the high-resolution geographic distribution of metal contaminants across urban areas. Thousands of soil samples were collected across Syracuse, NY to secure empirical evidence about such geographic distributions. Metal measurements were made with XRF technology, with quality assessments based upon replicate samples as well as ICP technology summarized here. Both metal covariations and their spatial structure are described, followed by mapping of selected metal measurements based upon sample points, as well as census block group and census tract aggregates. A simple comparison is presented between certain of these empirical results and a selected non-urban landscape (a river floodplain). Finally, implications drawn from the empirical evidence presented include covariation assessments with selected census data that serve as surrogates for poverty.     

Speciation of heavy metals in airborne particles, road dusts, and soils along expressways in China

This study analyzed the concentrations and chemical forms of Zn,Cu,Pb,Sb,Cd and Mn in airborne particles,road dusts and soils collected along three expressways in Jiangxi Province,China,with different traffic densities,and identified the levels and sources of heavy metal contamination.The concentrations of Zn,Cu,Pb,Sb,and Cd except Mn in airborne particles,road dusts and soils were all in direct proportion to traffic volume.Cd concentrations were low compared with other metals.For instance,the concentrations of Zn,Cu,Pb,Sb,Mn and Cd were 6.6,0.7,2.2,0.1,0.1 and 0.1μg·m-3in PM10along the Changjiu Expressway,792.8,241.4,248.3,9.6,340.5and 8.0 mg·kg-1in road dusts,and 201.1,143.2,59.5,9.5,338.9 and 2.3 mg·kg-1in soils,respectively,but in the case of the ratio of concentration to the environmental background value,most serious contamination was caused by Cd.The sources of the heavy metals were judged by comparisons of the chemical forms of the heavy metals in different environmental media.Pb and Mn in airborne particles were both derived from traffic;Pb in road dusts and soils resulted mainly from the use of leaded gasoline in the past;and Mn in road dusts and soils was derived from parent rocks.Zn,Cu,Sb and Cd in airborne particles,road dusts and soils were derived primarily from traffic,and differences in chemical forms of the heavy metals in different media were due to the interaction between heavy metals in airborne particles and organic matter and other surfaces in road dusts and soils.We also discussed the change of chemical forms of heavy metals in particles of different sizes and under different weather conditions.Bioavailability of heavy metals in airborne particles was much higher than that in road dusts and soils,especially Pb(0.676 in airborne particles,0.159 in road dusts and 0.095 in soils).     

河南新密典型富硒区土壤Se元素地球化学特征及空间分布规律

硒(Se)是人和动物体必需的微量元素之一。通过土地质量地球化学调查评价,发现新密市南部土壤富硒资源丰富,系统采集并分析了代表性的土壤(表层和深层土样)、农作物(小麦)及岩石样品,探讨了土壤Se元素的空间分布规律、富硒土壤成因及其生物效应。测试结果表明,土壤总Se含量介于0.06~3.99 mg/kg之间,Se元素平均含量为0.44 mg/kg。根据河南省富硒土壤评价标准,工作区圈定富硒土地面积103.7 km2。对土壤-岩石地球化学剖面进行分析,推断工作区土壤硒异常主要来源于成土母质、次生富集和人为作用。工作区大宗粮食作物小麦中品质较好,52.94%的样品为富硒小麦。     

Heavy metal contamination of urban soils and street dusts in Hong Kong

Due to rapid urbanisation and scarcity of land, most of the urban parks and recreational areas in Hong Kong are built close to major roads or industrial areas, where they are subject to many potential pollution sources, including vehicle exhaust and industrial emissions. An extensive soil survey was conducted in urban parks of Hong Kong to study the current conditions of heavy metals contamination in soils. Soil samples and associated street dusts were collected from more than 60 parks and public amenity areas in old urban districts, industrial areas and New Towns of the territory. Soils were also sampled in the remote country parks to establish the baseline conditions. The total concentrations of heavy metals and major elements in the samples were determined. The results indicate that urban soils in Hong Kong have elevated concentrations of Cd, Cu, Pb and Zn. The parks with high metal concentrations are located in old urban commercial districts and industrial areas, indicating that the major contamination sources in these soils are traffic emissions and industrial activities. In addition, the application of Cd containing phosphate fertilizers may be an important source of Cd in urban park soils. The street dusts have highly elevated Zn concentration, particularly along the main trunk roads. The high Zn content in the street dusts may come from traffic sources, especially vehicle tyres. Selective soil and road dust samples were also analysed for potential chemical speciation by a sequential chemical extraction method. The chemical partitioning results show that Pb and Zn are mainly in the carbonate/adsorbed and Fe–Mn oxide phases, while Cu is largely associated with the organic and sulphide fractions. The high exchangeable Cd in urban soils and high concentration of Zn in street dusts need further investigation for their ecological and health implications.     

Trace element concentrations of soils, plants and waters caused by a copper smelting plant and other industries, Northeast Turkey

The study area is situated in a large agricultural field which produces tobacco, maize, and other yearly cultivated vegetables in Tekkeköy, Samsun (NE-Turkey). In addition, a significant part of this area to the north along the Black Sea coast is occupied by several industrial plants such as a copper smelting plant (KB?), a fertilizer plant (Tügsa?) and industrial park facilities (IPF). In order to reveal their environmental impacts, heavy metal analyses were conducted on soil, plant leaves and water samples collected within an area of approximately 30 km² around these plants. Soil samples within an area of 10 km² around these facilities are found to be highly polluted with Cu, Zn, Pb, Fe and Mn. Pollution occurs at surface and sharply dies out at 20 cm downwards in soil profile. Since the region is polluted mostly with base metals, the copper smelting factory appears to be the main source of pollution as it processes the massive sulfidic ores of the Black Sea area. Plants show Cu, Pb, Zn and Fe pollution around KB? and Tügsa? and Cu and Pb around IPF. Pollutants observed in tobacco (Nicotiana tobacum) are Cu, Pb, Zn, Fe and S; in maize (Zea mays) Cu, Zn and Fe; and in cabbage (Brassica oleracea) Cu, Pb, Fe and S. The analyses of water samples collected from the study area reveal that Pb and, to a lesser degree, Cu and Fe pollution stem from KB?; Cu, Fe and Mn pollution from Tügsa?; Pb and minor amounts of Fe and Mn pollution from IPF. Factor analyses from analyzed metals and anionic complexes in water show three distinct groups: (a) an association of heavy metals with Na, K and Mg referring to pollution and acid leaching of soil, (b) an association of NH4, Fe, SO₄, Cl and Br indicating agricultural pollution and sea-water invasion in land near the shore line, and (c) HCO₃ behaving in a different manner in heavy metal precipitation.     

Public space design as class warfare: Urban design, the `right to the city' and the production of Clinton Square, Syracuse, NY

Urban designers and their design process remain largely outside the literature on public space. Either designers are cast as simple tools of capitalist social relations, producing exclusionary public spaces, or they figure as entrepreneurs that complement economic renewal schemes through beautification measures that bring business and jobs to the city. This paper analyzes both of these arguments, through an ethnographic analysis of the urban design process behind the redevelopment of a public square in Syracuse, NY. I argue that aesthetic considerations most often derive from economic and political pressures, pressures that draw upon the social contexts of urban designers within an international division of labor and their relationship to class struggle. Because public space serves such an important role in political and social life, its status as a product of urban design should therefore act as a crucial component in any discussion of rights to the city.     

Deciphering factors controlling trace element distribution in the soils of Karaduvar industrial-agricultural area (Mersin,SE Turkey)

In this study, 30 topsoil samples were collected from Karaduvar area (Mersin, SE Turkey) where at present various industrial and agricultural activities are occurring. Using a five-step ultrasound-assisted sequential extraction (UASE) procedure, trace elements in soil samples were partitioned into the following: (1) soluble-exchangeable; (2) bound to carbonates; (3) bound to Fe- and Mn-oxides; (4) bound to organic matter and sulfide compounds, and (5) residual fraction. Concentrations of 11 trace elements in the extracts were determined using ICP-MS. Total concentrations ranged between (in mg kg⁻¹) 3.35 and 7.26 for As; 1.18 and 3.96 for Cd; 10.76 and 20.26 for Co; 37.99 and 63.48 for Cr; 18.55 and 243.1 for Cu; 338.7 and 565.6 for Mn; 4.42 and 6.44 for Mo; 148 and 279.3 for Ni; 10.12 and 73.71 for Pb; 17.93 and 36.55 for V, and 25.46 and 331.7 for Zn. Factor analysis was applied to dataset in order to discriminate between natural and anthropogenic pollution sources and factors controlling the spatial distribution of trace elements in the area. Results suggest that distributions of Co, Cr, Mn, and Ni are mainly controlled by lithological factors, whereas, distributions of Cu, Pb, and Zn can be attributed to agricultural activities such as pesticide/herbicide use and fertilizer application, as well as irrigation with petroleum hydrocarbon-contaminated groundwater. Highest concentrations of Cd and Mo are generally observed around the diesel-fired thermal power plant and ATAŞ refinery. Highest concentrations of As and V are generally observed at the NW sector of the area; however, no definitive source can be designated for both of these elements.     

Ichnoentomology: insect traces in soils,palaeosols and other substrates

Ichnology is the science that studies traces, mostly trace fossils, which are defined as morphologically recurrent structures (nests, burrows, trackways) resulting from the life activity of an individual organism modifying the substrate. Leonardo da Vinci was probably the first ichnologist. He mentioned the existence of traces of worms in rocks. Trace fossils reflect how extinct animals behaved. They are as parts of a time machine that allow us to almost see how extinct animals made their nests, fed, reproduced and walked. Moreover, they allow us to reconstruct palaeoenvironments and the evolutionary history of many taxa. Ichnology was originally developed by geologists; traces first caught our attention in rocks (palaeoichnology) and then in extant environments (neoichnology). For many years ichnology was only studied in marine or lacustrine environments, whereas terrestrial ichnology has been developed over the last few decades. Insect traces are the most common in terrestrial environments, such as palaeosols, but they are also common in plant remains, bones, and in some subaquatic substrates. Ichnoentomology deals with insect traces in soils, palaeosols and other substrates.     

Trace element distribution in the soils above deeply weathered pegmatites, Virginia, U.S.A.: implications for exploration

Chemical partitioning data are of fundamental interest to exploration geochemists. This paper is one of the few studies which has investigated the relative proportions of the rare elements in various soil extracts. The dispersion of trace elements from weathering pegmatites in Powhatan Country, Virginia, was found to be restricted to the immediate vicinity of the pegmatites. A sequential extraction procedure was used to measure the distribution of Be, La, Nb, Sn, U, Li, and Ni,among the following fractions of the B soil horizons: exchangeable, Fe and Mn oxyhydroxide, residual, and aqua regia digestion. The elements Sn, Be, Li, and U were found to be associated with soils over the complex Herbb No. 2 pegmatite, whereas La and Ni were generally associated with the background soils.A geochemical exploration model was developed using stepwise discriminant function analysis to determine the combination of elements and soil extracts that best differentiates between complex pegmatitic, simple pegmatitic, and background soils. Log-transformed aqua regia extract concentrations of Sn, La, U, and Li were the most effective variables when used to separate complex pegmatitic from simple pegmatitic soils.     

Hazard assessment on arsenic and lead in soils of Castromil gold mining area,Portugal

Castromil is one of the Au mining areas in Portugal that has been abandoned since 1940. Due to the lack of regulations and environmental education, Castromil is now a residential area suffering from the considerable consequences of poorly regulated mining activities; tailings, shafts and adits are present. Geochemical data related to environmental studies in old mining areas frequently show extremely high values and very skewed distributions that need to be properly addressed. Agricultural soils from this region have high concentrations of As and Pb. In this study, the Box–Cox transformation and geostatistics were applied to study heavy element (As and Pb) concentrations in soils in order to characterize the hazard posed by them in the area. This provides a decision support tool to define the areas where remedial action is needed in light of the risks to humans and ecosystems and for contaminant migration. The results discussed here take into account the hazard-based standards for soils as target and intervention values.     

Rhodium, gold and other highly siderophile element abundances in chondritic meteorites

The abundances of the highly siderophile elements (HSE) Re, Os, Ir, Ru, Pt, Rh, Pd and Au, and ¹⁸⁷Os/¹⁸⁸Os isotope ratios have been determined for a set of carbonaceous, ordinary, enstatite and Rumuruti chondrites, using an analytical technique that permits the precise and accurate measurement of all HSE from the same digestion aliquot. Concentrations of Re, Os, Ir, Ru, Pt and Pd were determined by isotope dilution ICP-MS and N-TIMS analysis. The monoisotopic elements Rh and Au were quantified relative to the abundance of Ir.Differences in HSE abundances and ratios such as Re/Os, ¹⁸⁷Os/¹⁸⁸Os, Pd/Ir and Au/Ir between different chondrite classes are further substantiated with new data, and additional Rh and Au data, including new data for CI chondrites. Systematically different relative abundances of Rh between different chondrite classes are reminiscent of the behaviour of Re. Carbonaceous chondrites are characterized by low average Rh/Ir of 0.27 ± 0.03 (1s) which is about 20% lower than the ratio for ordinary (0.34 ± 0.02) and enstatite chondrites (EH: 0.33 ± 0.01; EL: 0.32 ± 0.01). R chondrites show higher and somewhat variable Rh/Ir of 0.37 ± 0.07.Well-defined linear correlations of HSE, in particular for bulk samples of ordinary and EL chondrites, are explained by binary mixing and/or dilution by silicates. The HSE carriers responsible for these correlations have a uniform chemical composition, indicating efficient homogenization of local nebular heterogeneities during or prior to the formation of the host minerals in chondrite components. Excepting Rumuruti chondrites and Au in carbonaceous chondrites, these correlations also suggest that metamorphism, alteration and igneous processes had negligible influence on the HSE distribution on the bulk sample scale.Depletion patterns for Rh, Pd and Au in carbonaceous chondrites other than CI are smoothly related to condensation temperatures and therefore consistent with the general depletion of moderately volatile elements in carbonaceous chondrites. Fractionated HSE abundance patterns of ordinary, enstatite and Rumuruti chondrites, however, are more difficult to explain. Fractional condensation combined with the removal of metal phases at various times, and later mixing of early and late formed metal phases may provide a viable explanation. Planetary fractionation processes that may have affected precursor material of chondrite components cannot explain the HSE abundance patterns of chondrite groups. HSE abundances of some, but not all Rumuruti chondrites may be consistent with solid sulphide-liquid sulphide fractionation processes during impact induced melting.     

Finite element simulation of freezing processes in soils

The finite element method, formulated for non-linear heat conduction, allows the solution of practically any ground freezing problem. Stabilization of wet soils by artificial freezing and freezing under roads induced by cold winter conditions are considered in this paper. Special features of the program used include parabolic isoparametric elements, a new time stepping scheme and an improved procedure for the estimation of thermal properties.     

大气降尘及人工粉尘在缬氨酸中的溶解特性研究

针对自然降尘、工业区降尘及人工粉尘进行的物相、成分、表面形貌、元素含量及粒度分析表明,降尘均以石英、方解石、钠长石、绢云母为主要物相成分,SiO₂、CaO含量较高,K₂O、Na₂O含量低。降尘粒度在0.3～5 μm内集中分布,小于2 μm的粉尘比例均超过85%。粉尘颗粒多为无规则的团块状,且颗粒表面粗糙。在模拟人体温度37℃条件下,对比研究了32 h内粉尘在缬氨酸水溶液中的溶出行为和电化学作用。不同性质的粉尘的pH值和电导率变化趋势不尽相同,大体上前4 h前各粉尘样品的pH值、电导率随时间增加上升较快,8 h后反应基本达到平衡。反应前后,溶液pH值改变较小,缬氨酸对粉尘溶解有较大缓冲作用。粉尘中元素K、Ca、Na、Mg的离子溶出总量为31～331 mg/L,其中Ca元素的溶出量最大为15～255 mg/L,其次为元素K、Mg、Na。重金属离子Fe、Zn、Mn、Pb、Ba、Cr、Ni、V的离子溶出总量为3.06～20.60 mg/L,Al、Si离子溶出总量为1.12～22.80 mg/L。粉尘中各元素主要在前8 h溶出较快,各粉尘在中性缬氨酸水溶液中的溶解程度由大到小为: 硅灰石>蛇纹石>海泡石;水泥厂降尘>自然降尘>电厂降尘。CaO含量高的水泥厂降尘和硅灰石人工粉尘溶解程度最大,表明其在中性缬氨酸环境中耐蚀性较差,表现出较低的生物持久性。SiO₂含量高的电厂降尘和海泡石人工粉尘溶解程度最小,具有较强耐蚀能力和较高生物持久性。     

Endogenous and exogenous lead in soils of Yangtze River Delta region,China: identified by lead isotopic compositions and multi-elemental approaches

Thirty typical soil profiles were sampled in Yangtze River Delta (YRD) region and analyzed for stable lead (Pb) isotopes and total concentrations of Pb and scandium (Sc). Pb isotopic compositions of A-horizon and C-horizon and Pb/Sc ratio were combined to estimate the amounts of endogenous and exogenous Pb accumulated in topsoil and identify possible sources. The results indicated that Pb exhibits a trend of accumulation in topsoil at regional scale. The isotopic composition of endogenous Pb is characterized by a narrow range of isotope ratios, varying with parent material, while that of exogenous Pb is characterized by a comparatively wide range of isotope ratios, varying with anthropogenic source. Coal combustion is probably the most important anthropogenic source of exogenous Pb in the soils of YRD region, as identified by isotopic ratio cross-plot combined with multi-elemental approaches.     

Impact of metallurgy on the geochemical signature of dusts, soils and sediments in the vicinity of Elbasan complex (Albania)

An investigation of the metallurgical complex surroundings in Elbasani, Albania used background samples to rule out the level of contamination in the study area. Our results show that atmospheric dust particles and soils are of high concern while overbank sediments and actual river sediments are of lower concern. The heavy metals with concentrations of up to 5 times above the local background values are Zn, Cr, Ni, Cu, Fe and Co in soils; Fe, Cr, Co, Ni, Zn, Pb in dust particles; and, Cr and Zn in the actual river/stream sediments. Due to the small size of the dust particles and the atmospheric transportation mechanism primarily related to prevailing winds, the concern for the transport of dust particles is high, especially with respect to risks associated with inhalation. The people working and living in the vicinity of the metallurgical complex of Elbasani are at the highest risk of exposure. Concerns relating to soils are associated with the potential for translocation of the trace element particles into vegetation, in particular, within the upper part of the plants. Therefore, the consumption of the vegetables grown in the vicinity of the metallurgical site should be avoided. Special attention has been given to the Shkumbini river, where the long residence time of water and particulates may result in transitions of trace elements between dissolved and particulate phases downstream.     

Distribution and mode of occurrence of zinc and lead in glacial soils

The distribution and mode of occurrence of zinc and lead have been examined in glacial soils developed over a complex Precambrian marble-paragneiss terrain in the Adirondack Mountains of New York. Based on distribution within the soil profiles, zinc is enriched in the B₁ horizon of soils sampled over marble and lead is generally enriched in the A horizon, particularly in soils developed over paragneiss. Contrast is calculated using

Full-size image (1K)

, where is the mean of n_A anomalous and n_B background samples, and S_p is the pooled standard deviation) for zinc, lead and cold-extractable heavy metals in soils sampled over marble and paragneiss. The t-values indicate that the B₁, soil horizon is the most suitable for sampling on a regular basis, even though lead is most concentrated in the A horizon.The distribution of zinc and lead among exchangeable, organic, iron-manganese oxide, clay, silt and sand fractions of B₁ horizons from two anomalous and one background soil indicates that both zinc and lead are tied up principally in iron and manganese oxides. The anomalous samples exhibit zinc enrichment in the Fe-oxide digestion and high Mn/Fe ratios for the Mn-oxide digestion (as well as the total analysis). In terms of total contribution to the sample, significant proportions of zinc in the clastic fraction can be attributed to zinc substitution into clays plus the ineffective removal of Fe-oxides by the ammonium oxalate extraction procedure. Lead, on the other hand, occurs in significant concentrations in clay, silt and sand as well as Fe- and Mn-oxides, probably as a trace constituent in feldspars or adsorbed onto clay surfaces.     

安溪土壤—茶叶铅含量关系与土壤铅临界值研究

在福建安溪等地79个茶园采集了表层、亚表层土壤样和对应的茶叶样品,测定了茶叶铅含量和土壤常量组分、铅等微量元素组成。相关分析表明,茶叶与土壤铅含量呈显著正相关(P0.01),由此可建立一元线性回归方程,计算茶叶对土壤铅的迁移系数(Ft)。研究得出,茶叶铅迁移系数受土壤中Pb、Mn、P、Zn浓度的影响。依据茶叶铅质量标准,推算出茶园土壤铅安全临界值,结果表明,通常情况下由茶树根系从土壤中吸收的铅不会导致茶叶铅含量超标。以土壤铅存在形态及其生物有效性的理论研究成果为指导,结合影响茶叶铅迁移系数的土壤理化指标,建立的多元回归方程能更好地表征茶叶铅含量与土壤理化指标间的相互关系。     

Distribution and dispersion of lead and zinc in anomalous soils and stream sediments, Mount Hermon area, Israel

Geochemical field and laboratory tests of soils and stream sediments in an area of weak surficial lead-zinc mineralization resulted in the delineation of two anomalous zones. Lead-zinc values are exceptionally high, but downslope and downstream mobility is low.The metals occur in base-exchangeable positions (5%), with iron oxides (45–60%), in clay lattice positions (15–30%), as resistant minerals (2–5%), and in organic matter (up to 20%).Intense dissolution and redeposition of metals occurred probably close to their point of origin in residual soils.     

The high contents of lead in soils of northern Kosovo

A soil-based geochemical survey was carried out in an area of about 350 km² in northern Kosovo around the Zve?an Pb-Zn smelter. The concentrations of As, Cd, Co, Cr, Cu, Ni, Pb, Sb, Tl, Th, U, Zn were determined in 452 topsoil and 82 subsoil samples. High contents of Pb, Cd, As, Sb, Zn and Cu were found in topsoil over a vast area including the Ibar and Sitnica river valleys. The highest concentrations were usually measured close to the Zve?an smelter. In some zones, the lead contents in surface soils exceeded 5000 mg/kg. Arsenic and antimony levels were usually more than 200 and 50 mg/kg, respectively, while cadmium contents were in the range 5-20 mg/kg. South of the Zve?an area, lead, antimony and cadmium pollution was strong in the densely populated urban area of Kosovska Mitrovica and along the agricultural alluvial plain of the Sitnica River. Depending on the chemical element, the pollution extended 15-22 km north and south of the Zve?an smelter. There was a progressive decrease of heavy element concentrations with increasing distance from the smelting plant. The contents of Pb, Zn, Cu, As, Cd, Sb significantly decreased with soil depth; in fact, the pollution only affected the upper 50 cm of soil. Crops were affected by soil pollution and many food-stuffs exceeded the EU standards. Suggestions for soil remediation are given.