The Adsorption Properties of Agricultural and Forest Soils Towards Heavy Metal Ions (Ni,Cu, Zn,and Cd)

Adsorption of Cu, Cd, Ni, and Zn in single and multi-metal solutions by agricultural and forest soils was investigated in batch sorption experiments. The results showed significant differences in sorption capacities of the studied soils. The selectivity order was as follows: agricultural soil? top forest soil > bottom forest soil. The adsorption sequence Cu > Zn > Ni > Cd was established for the agricultural and bottom forest soil, while the order for the top forest soil was Cu > Ni > Zn > Cd. The experimental isotherms for the metal sorption were described satisfactorily by the Freundlich and Langmuir models. The competitive adsorption experiment indicated a reduction in the amount of metals adsorbed by the soils from the multi-metal solution compared to the single metal solution. Properties of the soils, such as pH, content of clay and organic matter, exchangeable bases and hydrolytic acidity, showed a significant influence on adsorption capacities of the studied soils.     

Accumulation Pattern of Inorganic Elements in Scaly Tooth Mushroom (Sarcodon imbricatus) from Northern Poland

Several studies have documented contamination levels and daily intake of metallic elements from foodstuffs including rice, maize, pulses, vegetables, fruits, fish, meat, egg, milk etc., however, limited literature is available on metal contamination levels in wild growing mushrooms and possible human exposure via consumption of it. Sarcodon imbricatus is an edible mushroom, commonly consumed in many parts of the world. Very few studies have been conducted on inorganic elemental composition in fruiting bodies (edible part) of this fungus. In this study, elements such as silver (Ag), aluminum (Al), barium (Ba), calcium (Ca), cadmium (Cd), cobalt (Co,) chromium (Cr), copper (Cu), iron (Fe), mercury (Hg), potassium (K), magnesium (Mg), manganese (Mn), sodium (Na), nickel (Ni), phosphorous (P), lead (Pb), rubidium (Rb), strontium (Sr) and zinc (Zn) were measured in caps and stems of fruiting bodies of S. imbricatus collected from the Wdzydze forests in Central and the Augustowska Primeval forest in Eastern Poland. Results revealed that a wide variation in concentrations of various metals in caps and stems samples collected from the two forests. Toxic metallic elements such as Cd and Hg showed preferential accumulation in caps than stems samples from both the forests. However, the concentrations of Cd, Hg and Pb in the mushroom samples were below the established weekly intake tolerance limits.     

Accumulation of Heavy Metals in Water,Sediments and Wetland Plants of Kizilirmak Delta (Samsun,Turkey)

In this study, concentrations of heavy metals (Fe, Mn, Ni, Co, Zn, Cu, and Pb) were measured in water bodies including streams, bottom sediments and various wetland plants of K?z?l?rmak Delta. K?z?l?rmak Delta is one of the largest and the most important natural wetlands in Turkey and has been protected by Ramsar convention since 1993. The heavy metal concentrations in water were found lower than that of national standards for protected lakes and reserves. In bottom sediments and wetland plants, however, the accumulated amounts of different heavy metals varied in the following order: Fe>Mn>Zn>Ni>Co>Cu>Pb, and Fe>Mn>Zn>Ni>Co respectively. Heavy metal uptake of Hydrocharis morsus-ranae and Myriophyllum verticillatum plants among others were found far above the toxic levels and they might be used as bio-indicators and heavy metal accumulators in polluted natural areas.     

Accumulation of Ag, Cd, Co, Cu, Hg, Ni and Pb in Pavlova viridis Tseng (Haptophyceae)

The flagellate alga Pavlova viridis Tseng was investigated in the laboratory for accumulation of the heavy metals, silver, cadmium, cobalt, copper, mercury, nickel and lead. The cultures were grown in an artificial seawater medium mixed with the individual metals at different concentrations. Based on data from the controls, the baseline metal concentrations in P. viridis were shown to be in an order of Cu > Pb > Co > Cd > Ni > Ag > Hg. In the experimental groups, the seven metals displayed different isotherm equilibrium patterns and the metal uptake capacity of the alga was Ni > Pb > Co > Hg > Cu > Cd > Ag at equilibrium. When assessed using the bioconcentration factors, metal accumulation by P. viridis was demonstrated to be the most efficient at a concentration of 0.001 mg L-1 for Ag, Cd and Co, and at 0.01 mg L-1 for Cu, Hg, Ni and Pb. This study suggests that P. viridis can be a source of mineral supplements in mariculture. The alga is not, however, recognized as an effective agent for removing heavy metals from wastewater. This revised version was published online in June 2006 with corrections to the Cover Date.     

Termite (Insecta: Isoptera) Species Composition in a Primary Rain Forest and Agroforests in Central Amazonia

Termites play important roles in organic matter decomposition, nutrient cycling, and soil structure in tropical rain forests. When forests are replaced by agriculture, termite species richness, abundance, and function often decline. We compared the termite assemblage of a primary forest site with that of a low plant diversity, palm-based agroforest (five plant species) and a high plant diversity, home-garden agroforest (10 plant species) using a rapid biodiversity assessment protocol. In comparing the primary forest termite species composition to previously published studies, we found soil feeders and the Apicotermitinae to be more dominant than previously reported in Amazonia. Thirty percent of the species belonged to the Apicotermitinae, and an unusually high percentage (57%) of species were soil feeders. Unexpectedly, the palm-based agroforest, despite its lower plant diversity, was closer to primary forest in termite species composition, rate of species accumulation, and proportions of species in taxonomic and functional classes than was the home-garden agroforest. This suggests that particular plant attributes may better determine the termite assemblage than plant diversity alone in these agroecosystems. Unlike other agroecosystems reported in the literature, Apicotermitinae and soil feeders were proportionally more abundant in these agroforests than in primary forest. The ability of agroforests to support populations of soil feeders has a potentially positive effect on soil fertility in these agroecosystems; insomuch as feeding guild is a proxy for function, these closed-canopy agroforests may be able to sustain the same termite-mediated functions as primary forest.     

Heavy Metals in Agricultural Soils of the Mouriki-Thiva Area (Central Greece) and Environmental Impact Implications

The heavy metal content of 51 surface soil samples from the agricultural region of Mouriki-Thiva (central Greece) was investigated by a combination of mineralogical (X-ray diffraction and scanning electron microscopy) and geochemical (aqua regia and 0.5 M HCl extractions) methods in order to determine the levels of contamination, as well as the origin, distribution and mobility of selected metals. The geology of the area includes ultrabasic rocks, and consequently the soils have anomalous values in Ni (621-2639 mg/kg) and Cr (134-856 mg/kg). Whereas Cr is mainly hosted in the crystal structure of chromite, Ni is primarily mobilized from olivine and serpentine. Nickel, and to a lesser extent Cr, were also found to be absorbed in Fe oxides. The results of a single 0.5 HCl leach revealed significant differences in the mobility and potential bioavailability of Ni and Cr in representative soil samples; Nickel is substantially more labile, and as a result a potential amount of this metal is readily available to the plants. The whole area is heavily contaminated by Ni and Cr and consequently the monitoring of the agricultural products of the region for their heavy metal content is strongly recommended.     

Larval mouthpart deformities in Procladius paludicola Skuse (Diptera: Chironomidae) from the Murray and Darling Rivers,Australia

A high incidence of ligula (mouthpart) deformities is reported for the larvae of Procladius paludicola Skuse (Diptera: Chironomidae) collected from sites on the Murray and Darling Rivers, Australia. This is the first report of deformities in Australian freshwater insects, and is discussed in relation to known toxic pollutants within the catchment.     

Laboratory investigation on community composition, emergence patterns and biomass of wood-inhabiting Chironomidae (Diptera) from a sandy lowland stream in Central Europe (Germany)

Wood-inhabiting chironomid communities were investigated from June 1998 to July 1999 by laboratory rearing of randomly collected submerged branches from a headwater and mid-reach site of a sandy lowland stream, separated by an impoundment used for fishery purposes. Total annual emergence (males and females) from headwater samples was higher (2551 ind m^–2 y^–1) compared to the mid-reach (1576 ind m^–2 y^–1), which could be due to disturbances caused by frequent impoundment openings resulting in high discharge events. Chironomid community from branches comprised three subfamilies, with Orthocladiinae (18 species, 2189 ind m^–2 y^–1) clearly predominating at the headwater (total of 36 species). Mid-reach samples (total of 48 species) showed similar emergent numbers of Orthocladiinae (19 species, 786 ind m^–2 y^–1) and Chironominae (26 species, 764 ind m^–2 y^–1). Tanypodinae were caught very rarely in the laboratory emergence (12 ind m^–2 y^–1 at both sites). Shannon-Wiener diversity index for the mid-reach chironomid community was higher (2.52) than for the headwater community (1.68). Chironomid species composition on woody debris was similar between stream sites, with a Sørensen index of 0.75, but showed different dominance structures indicated by a Wainstein index of 0.26. Total adult biomass (in the manner of dry mass) during the study period was higher for wood-dwelling chironomids from the headwater (158.2 mg m^–2 y^–1) compared to the mid-reach (123.8 mg m^–2 y^–1), but individual biomass was higher for mid-reach chironomids (0.079 mg ind^–1 vs. 0.062 mg ind^–1 at the headwater), indicating the predominance of larger species. Total biomass of wood-inhabiting chironomids in the investigated lowland stream was low compared to other field emergence studies, which could be attributed to the laboratory approach for investigating the emergence from a single substrate type (submerged wood) instead of the integrative field surveys where chironomids from all habitats were caught. Main reason for the lack of chironomid species closely associated to wood in this sandy lowland stream could be infrequent but episodic disurbances caused by the anthropogenic induced highly fluctuating discharge regime of the downstream study site.     

Copper sorption and accumulation by the extraradical mycelium of different Glomus spp. (arbuscular mycorrhizal fungi) isolated from the same polluted soil

The form and localisation of Cu accumulation in the extraradical mycelium (ERM) of three arbuscular mycorrhizal fungi (AMF), isolated from the same polluted soil contaminated with the Cu and Arsenate, was studied. There were differences in the capacity of the ERM of the three AMF to sorb and accumulate Cu. Glomus caledonium BEG133 had a significantly lower Cu-sorption capacity than Glomus mosseae BEG132 and Glomus claroideum BEG134 isolated from the polluted soil as well as an isolate of G. mosseae BEG25 from a non-polluted soil. This was directly related to the cation exchange capacity (CEC) of the ERM of these fungi. Transmission Electron Microscopy (TEM) and Scanning Electron Microscopy (SEM) linked to an energy dispersive X-ray spectrometer (EDAX) gave more detailed information, showing that the ERM of AMF from the polluted soil was able to accumulate Cu in the mucilaginous outer hyphal wall zone, cell wall and inside the hyphal cytoplasm. The EDAX spectra showed that the accumulated Cu was mainly associated with Fe in the mucilaginous outer hyphal wall zone and in the cell wall. Cu was associated with traces of arsenate inside the cytoplasm of the ERM of Glomus mosseae BEG132 but this was not visible inside the ERM of Glomus caledonium BEG133 or Glomus claroideum BEG134. This work suggests that the ERM of AMF is able to sorb and accumulate Cu, but different tolerance mechanisms exist between the three AMF isolated from the same polluted soil providing further evidence for functional diversity within populations of AMF in soils.     

Assessment of heavy metal contamination of rice grains (Oryza sativa) and soil from Ada field,Enugu, Nigeria: Estimating the human healtrisk

The concentrations of heavy metals in rice grains and soils from Ada cultivated fields were investigated. Rice and soil samples were digested and the heavy metal concentrations determined using atomic absorption spectrophotometer. The results showed the following concentrations of metals (mg/kg): soil—Pb (4.64 ± 2.18), Cd (0.83 ± 0.83), Zn (20.26 ± 18.60), Mn (68.90 ± 19.91), Ni (3.46 ± 2.42), and Cr (21.41 ± 14.6); rice—Pb (3.99 ± 1.43), Cd (1.10 ± 0.53), Zn (65.37 ± 58.09), Mn (37.81 ± 5.82), Ni (3.12 ± 1.49), and Cr (10.87 ± 6.47). The Canadian, Nigerian and Chinese maximum allowable concentration for cadmium in soil were exceeded by 15%, 30%, and 85% of the soil samples, respectively. Heavy metals in all the rice samples evaluated were found to be above the World Health Organization (WHO) maximum permissible limit for lead, cadmium, and chromium. Strong positive and significant correlations were observed between some metal pairs in soil and rice indicating the similarity in origin. The estimated daily intakes of Pb and Cd from rice grown on the fields were higher than the safety levels established by WHO and the Joint FAO/WHO Expert Committee Food Additive, respectively. Hazard quotients and total hazard index for Pb and Cd were greater than 1. This indicates that consumption of rice from these fields will likely induce adverse health effects arising largely from Pb and Cd exposure.     

Contamination and environmental risk assessment of heavy metals in marine sediments from Tahaddart estuary (NW of Morocco)

Abstract

The distribution, contamination status, and ecological risks of heavy metals in Tahaddart estuary were investigated. 24 surface sediment samples and two cores were collected and analyzed for major (Al and Fe), heavy metals (As, Cd, Cr, Cu, Ni, Pb, and Zn), and grain size composition. The heavy metals assessment was carried out using different environmental indices. The results indicated that the spatial distribution patterns of Al, Fe, and Zn were mainly determined by the distribution of the finer grained fraction (<63?μm) in the sediment. In contrast, As, Cd, Cr, Cu, Ni, and Pb concentrations were controlled by anthropogenic activities (vehicular traffic from Highway Bridge and thermal power plant). The distribution of heavy metals in sediment cores showed an upward enrichment in heavy metals with high concentration found in the uppermost may related to the increasing in human activities. The pollution indexes confirmed that the Tahaddart estuary sediment was considerably to high contaminated by heavy metals near to different anthropogenic inputs. Similarly, the potential ecological risk index and the biological risk index present 21% probability of toxicity posing potential risk to the aquatic organisms. These results provide basic information that can be used to protect and improve the quality of this ecosystem.     

Chelation of ThIV, EuIII and NdIII by dianionic N,N'-bis(pyridoxylideneiminato)ethylene, (Pyr2en)2-. On the search of feasible modelings for heavy metals damage inhibition in living beings

The neutral Schiff base N,N'-bis(pyridoxylideneiminato)ethylene {H(2)pyr(2)en} reacts with Th(NO(3))4.4H2O, NdCl3.6H2O and EuCl3.6H2O to give [Th(pyr(2)en)2(H2O)] (1), [Nd(pyr(2)en)(Hpyr(2)en)].12H2O (2) and [Eu(pyr(2)en)(Hpyr(2)en)] (3). In the three not yet reported bimolecular chelate systems the endo hydroxyl groups of the rings undergo deprotonation confirming the remarkable ability of the pyridoxal-containing ligand H(2)pyr(2)en to yield stable heavy metal chelates with unusual coordination polyhedra. Complexes 2 and 3 show a coordination number 8 for Nd and Eu, achieving a distorted quadratic antiprism. In complex 1 the additional water molecule increases the coordination number of Th to 9 producing a capped square antiprism. The synthesis and structural elucidation of the title complexes starting from a probably non-toxic metabolite like H(2)pyr(2)en should represent a useful contribution to the research on models of prevention and therapy of damage caused by radioactive and heavy elements.     

Two New and Two Recharacterized Species from a Radiation of Pristionchus (Nematoda: Diplogastridae) in Europe

Two new species of Pristionchus, P. lucani n. sp. and P. bulgaricus n. sp., are described from France and Bulgaria, respectively. Additionally, new morphological and morphometric data are provided for two previously described species from Europe, P. brevicauda (Kotlán, 1928) Paramonov, 1952 and P. clavus (von Linstow, 1901) Sudhaus and Fürst von Lieven, 2003. A phylogeny including these four species was inferred from a dataset including 26 ribosomal protein-coding genes, sequences of which are original for P. bulgaricus n. sp. and P. clavus. Relationships support a radiation of all sequenced European Pristionchus species from a single, gonochoristic common ancestor, and current knowledge of species ranges supports “western” and “eastern” clades. Similar diagnostic morphologies reflect the close relationships among the new and recharacterized species, especially P. bulgaricus n. sp., P. brevicauda, and P. clavus, although mating tests as well as genetic and phylogenetic separation support their identities as unique species. Our results show that Pristionchus species in Europe are more diverse than typological characters suggest, and thus biological and molecular profiling will be essential for future delimitation of Pristionchus species from the region.     

Effects of outbreak of the train millipede Parafontaria laminata armigera Verhoeff (Diplopoda: Xystodesmidae) on litter decomposition in a natural beech forest in Central Japan. 1. Density and biomass of soil invertebrates

Soil invertebrates were studied to determine the animals important in litter decomposition and soil formation in a natural forest of Fagus crenata Blume mixed with Quercus mongolica var. grosseserrata Rehd. et Wils., where outbreak of the adult train millipede, Parafontaria laminata armigera Verhoeff was recorded in 1980. The density and biomass of soil invertebrates, and their distribution in soil, were surveyed largely by hand sorting and also using Tullgren and Baermann apparatuses. The densities of soil macroinvertebrates were 10²–10³ individuals/m². Diplopoda was the most abundant among them, 87.3% of which was the train millipede. The total biomass in wet weight of soil macro-invertebrates was 34.9–70.5g/m² in 1980–1981, when the millipede was pre-adult or adult, and it decreased to 3.5–6.7g/m² in 1982–1984, when it was young. The density of soil invertebrates extracted by apparatuses was 10⁴–10⁶ individuals/m². The total biomass of these was estimated to be 5.8–10.8g/m². The majority of soil invertebrates lived in the A₀ horizon, whereas the train millipede lived in soil of the A₁+A₂ horizon. These results suggest that the train millipede is one of the most important soil invertebrates affecting soil properties. For evaluating the importance of the species, more than 8 years survey of hand-sorting together with the Tullgren apparatus was necessary, as the train millipede grew synchronously and had an 8-year life span and young stages of 1.5–3.5mm long.     

Effects of repeated (NH4)2SO4 application on sulfur pools in soil,soil microbial biomass,and ground vegetation of two watersheds in the Black Forest/Germany

The effect of repeated (NH₄)₂SO₄ applications (3 × 700 kg ha^–1 in 1988, 1991, and 1994, respectively) on S pools in soil, soil microbial biomass, and ground vegetation was studied at two Norway spruce (Picea abies L. [Karst.]) sites in the Black Forest/Germany. In both eco-systems, most of the total S pool was located in the soil. The soil also was the predominant compartment for retention of applied SO₄ ^2--S. The fractions of organic and inorganic S forms in the initial soil S content, and the retention of experimentally applied S was different for both sites. In the podzol Schluchsee, organic S accounted for 92% of total S. In the cambisol Villingen, the S pool consisted of 33% organic S and 67% inorganic S. The retention of applied S in various compartments of both ecosystems reflected these proportions. Only minor amounts of fertilized S (<1%) was retained in the spruce trees, ground vegetation, and soil microbial biomass. However, between 51% (Villingen) and 72% (Schluchsee) of the applied S was retained in the soil. In the Schluchsee podzol, 75% of retained fertilizer S was accumulated as ester sulfate, whereas SO₄ ^2-adsorption and precipitation of Al hydroxy sulfates were restricted by dissolved organic matter in the soil solution. In the Villingen cambisol, SO₄ ^2- adsorption was the dominant process of S retention, although 20% of the fertilized S again was retained as ester sulfate. The significant relevance of organic S forms in the retention of fertilizer S in both soils emphasizes the need for models which include the formation and re-mineralization of organic S compounds, especially of ester sulfates, for correctly simulating and predicting the retention and remobilization of S in acid forest soils subject to changing atmospheric N and S deposition.     

Microbial Biomass-C in Reclaimed Soil of the Rhineland (Germany) and the North Bohemian Lignite Mining Areas (Czech Republic): Measured and Predicted Values

This article compares reclaimed soils in the Rhineland lignite mining area, Germany (RA) and in the north Bohemian brown coal basin, Czech Republic (NBB). Because of highly significant differences of physical and chemical characteristics (RA was characterized by lower content of sand, clay, soil organic carbon, and total nitrogen) between both analyzed areas, the content of microbial biomass carbon (C_MB) differs significantly (p < 0.01): RA: 241.17 ± 96.50 μg C/g dry soil; NBB: 424.42 ± 136.23 μg C/g. Extracellular microbial carbon (C_EX) was also significantly higher in RA than NBB. The measured C_MB values from both mining areas were verified using two empirical mathematical models. Because our former model (used for evaluation of NBB) did not fit soils with low organic carbon content (0.10–0.80%), a new model was proposed. For evaluation of RA reclaimed sites the measured, model‐predicted, and calculated values were used. The best site in RA was Dürwiss Deponie (site 18 near Eschweiler), reclaimed in 1965 and characterized by good soil physical parameters (sand 4%, silt 77%, and clay 19%). In NBB undisturbed soils were the best, together with the site of Ú?ín (site 2 near Ústí and Labem), reclaimed in 1964, where high‐quality reclamation management resulted in high biological activity. According to biological criteria, the best management practice in NBB was use of high‐quality loam overlaying montmorillonite clayey subsoil. In RA direct reclamation of high‐quality loess with low content of sand also gave good results.     

河南南阳不同生境土壤重金属含量及其对拟水狼蛛生物学特性的影响

为了探明重金属含量对拟水狼蛛Pirata subpiraticus生物学特性的影响, 本研究于2008年7月在河南南阳地区5种不同生境下, 共采集50份土壤样本和150头拟水狼蛛样本, 采用原子吸收光谱法测定了5种不同生境下雌拟水狼蛛体内重金属含量, 并测定了雌蛛头胸甲宽、体重、卵袋重量、卵数目和卵体积等生物学指标。结果表明：不同样点拟水狼蛛重金属含量与土壤重金属含量显著正相关, 4个重金属污染区与宝天曼自然保护区（Baotianman, BTM）拟水狼蛛体内Cd、Cu和Zn的含量差异极显著(P<0.001), 桐柏铜矿（Tongbai Tongkuang, TBTK）和南阳油田(Nanyang Youtian, NYYT) 的Pb含量与BTM的差异极显著(P<0.001), 主成分分析表明Cd、Cu和Zn是反应重金属污染的主要指标。在重金属胁迫下, 4个重金属污染区与保护区的拟水狼蛛头胸甲宽、雌体重量、卵袋重量、卵数目和卵体积差异均达到极显著（P<0.001）或显著水平（P<0.05）, 主成分分析表明背胸甲宽、卵袋重量和卵体积是重要生物学指标。 拟水狼蛛的背胸甲宽、卵袋重量和卵的体积与重金属含量显著相关, 重金属含量高的地方拟水狼蛛背胸甲宽较小, 雌性体重、卵袋重量和卵数目较小, 卵的体积大, 因此说明拟水狼蛛处在逆环境中时, 动物为保持总的繁殖力不变的前提下, 后代个体的大小与数目间满足某种平衡, 即达到协同进化的目的, 拟水狼蛛可以作为重金属污染的监测指示生物。     

Habitat-specific composition of morphotypes with low genetic diversity in the green algal genus Klebsormidium (Streptophyta) isolated from biological soil crusts in Central European grasslands and forests

Terrestrial filamentous green algae of the widely distributed, cosmopolitan genus Klebsormidium (Klebsormidiophyceae, Streptophyta) are typical components of biological soil crusts (BSCs). These communities occur in all climatic zones and on all continents, where soil moisture is limited or where there has been disturbance. BSCs form water-stable aggregates that have important ecological roles in primary production, nitrogen fixation, nutrient cycling, water retention and stabilization of soils. Although available data on Klebsormidium are limited, its functional importance in BSCs is regarded as high. Therefore, in the present study Klebsormidium strains were isolated from BSCs sampled from various grassland and forest plots of different land use intensities in Central Europe, as provided by the Biodiversity Exploratories, and its intraspecific genetic diversity was evaluated. Previous phylogenetic analyses revealed a relationship between sequence similarity and habitat preference with a higher genetic diversity than expected from a morphological classification. We isolated and sequenced 75 Klebsormidium strains. The molecular phylogeny based on the ITS regions showed that all strains belong to either the previously described clade B/C or clade E. This classification was supported by morphological characteristics: strains assigned to clade B/C were identified as Klebsormidium cf. flaccidum or Klebsormidium cf. dissectum, and strains from clade E as K. nitens or Klebsormidium cf. subtile. Within one clade the strains showed low sequence divergences. These minor differences were independent of the sampling region and land use intensity. Interestingly, most of the strains assigned to clade E were isolated from forest sites, whereas strains from clade B/C occurred equally in grassland and forest sites. Therefore, it is reasonable to assume that habitat with its microenvironmental conditions, and not biogeography, controls genetic diversity in Klebsormidium.     

Spatial patterns,hotspot, and risk assessment of heavy metals in different land uses of urban soils (case study: Malayer city)

A study on identification of hotspots, spatial patterns, and risk evaluation of heavy metals in urban soils of Malayer city (Iran) was carried out. Fifty-nine composite surface soil samples were collected from six different land uses (urban parks, streets, and squares, boulevards, residential and agricultural areas) in Malayer city, and the total heavy metals were measured by atomic absorption spectroscopy. Average concentrations of Cd, Pb, Cu, and Zn, As, Cd, and Pb were 0.66, 15.51, 12.25, and 96.8 mg/kg, respectively. Among the six land uses, heavy metal contamination was heavier for street, while low contamination could be found for residential and urban parks. The spatial distribution of Pb in surface soil was similar to those of Cd, and Cu was similar to those of Zn with decreasing values from the central areas to the suburb. Also, there were several hotspots for studied heavy metals that Cd and Pb were mainly occurred in locations of heavy traffic in the city center and Cu and Zn in the west and northwestern in the city. The calculated result of risk evaluation showed that much of the city suffered from moderate to severe pollution by four of these heavy metals.