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1.
This study was carried out to determine the flux of nutrients and heavy metals from the Melai sub-catchment into Lake Chini through the process of erosion. Melai River is one of the seven feeder rivers that contributed to the present water level of Lake Chini. Three properties of soils, such as particle size, organic matter content, and soil hydraulic conductivity and three chemical soil properties, such as available nutrients, dissolved nutrients, and heavy metals, were analyzed and interpreted. Potential soil loss was estimated using the revised universal soil loss equation model. The results show that the soil textures in the study area consist of clay, silty clay, clay loam, and sandy silt loam. The organic matter content ranges from 3.40 to 9.92 %, while the hydraulic conductivity ranges from 5.2 to 25.3 cm/h. Mean values of available P, K, and Mg amount was 8.5 ± 3.7 μg/g, 24.5 ± 3.4 μg/g, and 20.7 ± 18.6 μg/g, respectively. The highest concentration of soluble nutrients was SO 4 ?2 (815.8 ± 624.1 μg/g), followed by NO3 ?-N (295.5 ± 372.7 μg/g), NH4 +-N (24.5 ± 22.1 μg/g) and PO4 3? (2.0 ± 0.8 μg/g). The rainfall erosivity value was 1658.7 MJ mm/ha/h/year. The soil erodibility and slope factor ranges from 0.06 to 0.26 ton h/MJ/mm and 7.63 to 18.33, respectively. The rate of soil loss from the Melai sub-catchment in the present condition is very low (0.0028 ton/ha/year) to low (18.93 ton/ha/year), and low level flow of nutrients and heavy metals, indicating that the Melai River was not the contaminant source of sediments, nutrients, and heavy metals to the lake.  相似文献   

2.
Studies on seasonal changes of heavy metal concentration in soils provide vital information for best management options at all times. The study investigated temporal variation in concentration of heavy metals in three towns having automobile service centres in Imo State. The study site is characterized by two major seasons in a year. Heavy metals were found in both arable and automobile soils, but more concentrations were recorded on the latter. Mean values of Cd, Cr, Ni, Hg and Pb were 6.2 mg/kg, 4.7 mg/kg 6.5 mg/kg, 0.02 mg/kg and 71.9 mg/kg respectively in the dry season while 2.9 mg/kg Cd, 2.2 mg/kg Cr, 1.9 mg/kg Ni, 0.01 mg/kg Hg and 51.9 mg/kg Pb were recorded during the rainy season of the experimental period. Higher values of heavy metal concentration were found in automobile soils as follows: 18.1 mg/kg Cd, 12.0mg/kgCr, 16.3 mg/kg Ni, 4.8 mg/kg Hg and312.8 mg/kg Pb in rainy season, and 15.1 mg/kg Cd, 8.1 mg/kg Cr, 11.9 mg/kg Ni 2.7 mg/kg Hg and 267.9 mg/kg Pb. However, Cd showed highest variability in arable soils during the dry season (CV=79%) while Hg varied widely in automobile soils in the rainy season (CV=54%).  相似文献   

3.
This communication presents the results of preliminary investigation of the characteristic levels of heavy metals in surface soils of an oilfield in the Niger Delta. The results indicate higher concentration of the following metals: Cd, Pb, Cu; Ni, Zn, Cr, Mn and Hg in soils around the gas plant than the pipeline areas. There is a significant temporal and spatial variation in the concentrations of the heavy metals. Samples collected during the wet season showed lower concentrations of heavy metals. The distribution pattern of heavy metals follows the following order Fe> Mn> Zn> V> Cr> Pb> Cu> Ni> Cd> Hg> As. The soils around the oilfield could be considered unpolluted since the concentrations of the metals fit into background levels and concentrations found in natural and agricultural soils. Since metal build up is a gradual process, farmland, fishing ponds and water bodies closer to these facilities will be at risk of heavy metal pollution over time.  相似文献   

4.
This article presents the results on distribution and enrichment pattern of acid-leachable trace metals (ALTMs) from roadside soil of Miri city, Sarawak, East Malaysia. The city is one of the fastest developing in the Malaysian region with huge petroleum resources. ALTMs Fe, Mn, Cr, Cu, Ni, Co, Pb, Zn and Cd along with organic carbon and carbonates (CaCO3) were analyzed in 37 soil sediments collected from roadside. The enrichment of ALTMs [especially Cu (0.4–13.1 μg g?1), Zn (9.3–70.7 μg g?1), Pb (13.8–99.1 μg g?1)] in the roadside soils indicate that these metals are mainly derived from sources related to traffic exhausts, forest fires and oil refineries. The comparative study and enrichment pattern of elements indicates that Mn, Cu, Zn and Pb are enriched multi-fold than the unpolluted soil and Ni, Pb, Cd in some samples compared to Sediment Quality Guidelines like Lowest Effect Level (LEL) and Effects Range Low (ERL) in the region which is mainly due to the recent industrial developments in the region.  相似文献   

5.
Tepanosyan  G.  Sahakyan  L.  Belyaeva  O.  Beglaryan  M.  Pipoyan  D.  Hovhannisyan  A.  Saghatelyan  A. 《中国地球化学学报》2020,39(4):487-496
Acta Geochimica - To study organochlorine pesticides and organophosphorus pesticides contents and assess pesticide-induced health risk in Armenia, the contents of pesticides were determined in 252...  相似文献   

6.
This study investigated the status and distribution patterns of selected heavy metals in roadside soils along Irbid-North Shooneh Highway, Jordan. This highway has experienced a growing number of vehicles that are likely to influence the levels of heavy metals in the surrounding agricultural lands. The average concentrations of Cr, Co, Cd, Cu, Pb, Zn, and Ni were 16.0, 36.0, 11.0, 4.0, 79.0, 122.0, and 60.0 mg/kg, respectively. Cd, Pb, and Co showed average levels that are higher than the average world soil background values. Elevated levels of heavy metals were measured in surface soil layer which decreased with depth, and with distance from the roadway. The contamination factor (CF), pollution load index (PLI), single ecological risk (Ei), potential ecological risk index (PERI), and geo-accumulation index (Igeo) generally indicated that the roadside soils are contaminated with Cd, Pb, and Ni. Heavy metals in soils are of geogenic and anthropogenic origins. Weathering of parent rocks in Wadi Al-Arab catchment is the primary natural source, whereas agrochemicals, vehicle exhausts, degradation of surface wear and paint of vehicles, vehicle wear debris of tire, and brake lining are the main anthropogenic sources of heavy metals.  相似文献   

7.
The Penjom gold deposit lies on the eastern side of the Raub‐Bentong Suture line within the Central Belt of Permo‐Triassic rocks, near Kuala Lipis, Pahang, Malaysia. The geology of the deposit is dominated by a sequence of fine‐ to coarse‐grained rhyolitic to rhyodacitic tuff, tuff‐breccia and a minor rhyolitic–rhyodacitic volcanic series, associated with argillaceous marine sedimentary rocks consisting of shale with subordinate shalely limestone of Padang Tungku Formation and Pahang Volcanic Series. Fine‐ to coarse‐grained tonalite and quartz porphyry intruded this unit. The main structural features of the area are north–south‐trending left‐lateral strike‐slip faults and their subsidiaries, which generally strike north–south and dip moderately to the east (350°–360°/40°–60°). Mineralization at the Penjom gold deposit is structurally controlled and also erratic laterally and vertically. The gold mineralization can be categorized as (i) gold associated with carbonate‐rich zones hosted within dilated quartz veins carrying significant amount of sulfides; (ii) gold disseminated within stockwork of quartz–carbonate veins affiliated with tonalite; and (iii) gold often associated with arsenopyrite and pyrite in quartz–carbonate veins and stringers hosted within shear zones of brittle–ductile nature in all rock types and in brittle fractured rhyodacitic volcanic rocks. Sphalerite, chalcopyrite, tetrahedrite and pyrrhotite are the minerals accompanying the early stage of gold mineralization. These minerals also suffered from local brittle deformation. However, most of the gold mineralization took place after the deposition of these sulfides. Galena appears somewhat towards the end of gold mineralization, whereas tellurium and bismuth accompanied gold contemporaneously. The gold mineralization occurred most probably due to the metamorphogenic deformational origin concentrated mostly in the shear zone. The mineralization is strongly controlled by the wall rock (e.g. graphitic shale), the sulfide minerals and fluid–rock interaction.  相似文献   

8.
This paper aims to determine the correlation between Cd, Cu and Pb concentration in the sediment and in five aquatic plants sampled during wet, normal and dry seasons. Analyses of the sediment showed that concentrations of exchangeable Cd and Cd after acid reduction were higher during the wet season (October) than on other sampling dates with mean values of 0.18 and 0.29 μg g−1, respectively. The concentration of Cu in the organic oxidation phase was higher in the normal season (January) than on other sampling dates with a mean value of 11.1 μg g−1. The concentrations of exchangeable Pb and that in the residual phase were higher during the wet season than on other sampling dates with mean values of 1.05 and 9.18 μg g−1, respectively. Cd and Pb concentrations in the leaves, stems and roots varied between sampling dates with a reduced concentration during dry season (July) and the highest metal concentrations (Cd and Pb) during wet season. There were positive correlations between Cd and Cu concentrations in the plant tissues (leaves, stems and roots) of most aquatic plants in the acid reduction fraction. Conversely, there was no positive correlation between Pb concentration in the plant tissues of all aquatic plants and the acid reduction fraction of the sediment.  相似文献   

9.
《Applied Geochemistry》2001,16(11-12):1405-1411
Contamination of soils by potentially toxic elements (PTEs) (e.g. Zn, Cu, Ni, Cr, Pb, Cd) from amendments of sewage sludge is subject to strict controls within the European Community in relation to total permissible metal concentrations, soil properties and intended use. This paper highlights the need for ecotoxicological data for the assessment of PTE impacts in addition to geochemical data alone. The soil microflora plays an essential role in determining levels of soil fertility, being intimately associated with the biogeochemical cycling of essential plant nutrients and the turnover of organic carbon. The measurement of soil microbiological parameters can provide insight into the impact of PTEs upon soil fertility, where geochemical analysis alone can often be inadequate to assess contaminant effects on essential components of the soil ecosystem. Microbial investigations were conducted on soils sampled from a well-controlled field experiment previously amended with specific types and rates of sewage sludge. Key microbiological parameters measured included the activity of the dehydrogenase enzyme and the presence and number of effective nitrogen fixing cells of Rhizobium leguminosarum biovar trifolii capable of nodulating the host plant, white clover (Trifolium repens). Results were evaluated with respect to maximum permissible concentrations of PTEs in sludge amended soils, as stipulated under UK limit values and the European Directive 86/278/EEC. Important effects on the size of the Rhizobium population and dehydrogenase activity were apparent in soils samples in relation to the soil pH, sludge type, addition rates and the concentrations of PTE present.  相似文献   

10.
The Raniganj Coalfield is the oldest coalfield in India that has been continuously and extensively mined since the late eighteenth century. The present study reports a geochemical investigation and environmental quality assessment using soil and water in the area surrounding a stream, locally known as Singaran Nala (Nala means storm water drains in Bengali), in the Raniganj Coalfield. Soil (top soil, mud, silty clay and laterite) and rock samples (sandstone and shale) were collected from the study area and were analyzed for trace metals (Cr, Cu, Fe, Mn, Ni and Zn). Surface waters from the stream and the Damodar River as well as ground waters from hand pumps and underground mine pits were collected. Water samples were analyzed for major ions (Na^+, Ca^2+, Mg^2+, Cl^-, HNO3^- and SO4^2-) and trace metals (Cu, Fe, Mn, Ni, and Zn). Trace metal concentrations in soil samples are found higher than the average world soil composition. Nevertheless, trace metal (Cr, Cu, Ni and Zn) concentrations in soils exceed or reach the maximum allowable concentrations (MAC) proposed by the European Commission for agricultural soils. In particular, Ni concentrations exceed the typical value for cultivated soils. Chromium, Cu and Ni concentrations in laterite and Cr concentration in topsoil exceed the ecotoxicological limit.  相似文献   

11.
Heavy metals are the focus of much interest because of their environmental persistence, toxicity, and mobility in soils. Some of the Chinese soils have been contaminated with heavy metals due to expansion of mining industries, pesticides usage, and other anthropological activities, which made the agro-ecosystem to become contaminated. The objective of this review is to illuminate the current pollution status, sources of heavy metals, transport mechanisms, and the factors affecting their mobility in Chinese soils. The additional studies in the future will present on source identification and the heavy metal transport characteristics in soil.  相似文献   

12.
The study was conducted with the selected soil profile of burnt (soil around brick kilns) and unburnt (agricultural land) soils in the Dinajpur, Rangpur, Rajshahi, Khulna and Patuakhali districts at the western part of Bangladesh to evaluate the effects of brick kilns on soil degradation and environmental pollution. The pH values of the unburnt soils increased as a function of the soil depth for Rangpur, Khulna and Patuakhali, while decreased for the soil profiles in Dinajpur. Burning of soils significantly (p<0.05) decreased the average pH values of soils by 0.4 pH units (7 % increased over average content = IOAC), but strikingly increased the average EC values from 0.26 to 1.77 mS/cm (592 % IOAC) and the effect was pronounced with the depth function. The average sand content of the soil profiles increased by 330%, while the silt and clay contents decreased by 49 and 40 %, respectively. The average losses arising from the burning of agricultural soils were amounted to 63% for organic matter, 56 to 86 % and 23 to 88 % for available and total N, P, K and S, respectively. This huge loss through the burning of 1 m deep soil profile, i.e. almost 3/4th of the deterioration of soil fertility is not only reducing the crop production but also polluting the associated environment and atmosphere. The burning of enormous C, N and S not only degrade the agricultural soils but also contributing to the changes in the global climate.  相似文献   

13.
This paper presents an evaluation of different chelating agents for their effectiveness in removing Cu, Co and Zn in three distinctly different types of sludge-amended soils. Soil types (Luvisol, Arenosol and Vertisol) were each mixed with an anaerobically digested sludge at a 1:1 ratio followed by leaching with three types of chelating agents, namely: ethylenediamine tetra acetic acid, nitrilotriacetic acid and acetic acid. Aqua regia method was used to quantify pseudo total metal before and after treatment. Generally, chelating agents can be out competed by soil colloids in attracting cations. The efficiency of chelating agents was found to follow this order ethylenediamine tetra acetic acid?<?nitrilotriacetic?=?acetic acid in all the three metals, with ethylenediamine tetra acetic acid being the most effective chelating agent. More heavy metals were removed in Luvisol and Arenosol than in Vertisol implying that soils rich in clay fraction retain more cations than soils with minimal clay fraction. Similarly, copper responded positively to chelation than zinc and cobalt in Luvisols and Arenosols, although the results were not conclusive for Vertisols.  相似文献   

14.
An increase in heavy metal pollution in the soils of Hassi Messaoud (Algeria) due to intense industrialization and urbanization has become a serious environmental problem. There are three large industrial complexes that have been established in the region of Hassi Messaoud for petroleum extraction field and refinery. The region hosts several industrial facilities which are the main sources for hazardous wastes. Surface soil samples from 58 sampling sites (systematically sampled; 1 × 1 km regular grid), including different functional areas in Hassi Messaoud, were collected and analyzed. The results showed that the average concentrations of Cu, Ni, Mn, Pb and Zn in soil of Hassi Messaoud were up to 13.17, 35.78, 121.21, 130.97 and 61.08 mg/kg, respectively. Ni concentrations were comparable to background values, while Cu, Mn, Pb and Zn concentrations were higher than their corresponding background values. Among the functional areas, the industrial regions displayed the highest metal concentrations, while the lowest concentrations occurred in rural soil. Principal component analysis coupled with cluster analysis showed that: (1) Pb and Zn had anthropogenic sources; and (2) Ni, Cu and Mn were associated with parent materials. Contaminations in soils were classified as geoaccumulation index and enrichment factor. Pollution index values of Cu, Ni, Mn, Pb and Zn varied in the range of 0.04–5.41, 0.46–2.49, 0.01–5.73, 0.62–152.9 and 0.09–53.01, with mean values of 1.32, 1.08, 1.26, 5.64 and 3.1, respectively. The integrated pollution index (IPI) of all the analyzed samples varied from 0.42 to 31.59, with a mean of 2.48, and more than 5.45 % of samples are extremely contaminated; 18.18 % are heavily contaminated; 60 % are moderately contaminated; and others are low contaminated. The spatial distribution of IPI showed that desert and rural areas displayed relatively lower heavy metal contamination in comparison with other areas.  相似文献   

15.
Groundwater pollution is a major global environmental issue especially in the large cities and trace metals are considered as most important aquatic pollutants. The present study is based on the measurement and characterization of various physicochemical parameters (pH, EC, TDS, DO, alkalinity, hardness, and chloride), major cations (Ca, Mg, Na and K) and selected trace metals (Sr, Li, Fe, Zn, Cu, Co, Mn, Ag, Cd, Cr, Ni, and Pb) in the groundwater of Lahore, Pakistan during summer and winter (2017–18) seasons. Groundwater is the main source of drinking water in urban areas of Lahore. Seasonal comparison of the data indicated that majority of the metals showed relatively higher concentrations during winter than summer. Most of the metals exhibited significant spatial variability during both seasons; relatively higher metal levels were found in the old settlements and thickly populated areas of the city. Average concentrations of Pb, Ni, Cd and Co in the groundwater were found to be higher than the national and international guideline values. Factor analysis and cluster analysis revealed major anthropogenic contributions of Ni, Co, Cd, Cu, Cr and Pb in the groundwater while rest of the metals showed mixed and/or natural contributions. Evaluation of human health risks for the metal contents in groundwater revealed that Pb, Co, Ni and Cd were associated with significantly higher non-carcinogenic risks (HQing > 1); the calculated risk for children was considerably higher than the adults. Moreover, the carcinogenic risk associated with Ni, Cr, Cd and Pb exceeded the safe limits. The present study revealed significantly higher anthropic pollutants in the groundwater which imposed considerable risks to human; therefore, it is recommended to implement immediate remedial measures to ensure safe drinking water.  相似文献   

16.
Understanding of the landscape response to agricultural practices mainly in relation to soil trace metals requires particular attention. Consistent with this, the trend and possible pollution of total and DTPA fraction of Mn, Zn, Cu, and Cd in the agricultural soils developed on different landscape positions involving piedmont alluvial plain (PAP), river alluvial plain (RAP), plateau (PL), and lowland (LL) were investigated. The content of the metal in different soil profiles, grouped by landscape positions, varied in the following orders: total and DTPA-Mn as LL > PAP > RAP > PL, total Zn and Cu as PAP > RAP > LL > PL, total Cd as RAP > PAP > PL > LL, DTPA-Zn as RAP > PAP > PL > LL, and DTPA-Cu as RAP > LL > PL > PAP. A wide variation in the total fraction of Mn (89–985 mg kg?1), Zn (24–152 mg kg?1), Cu (8–27 mg kg?1), and Cd (0.6–1.7 mg kg?1) and in the DTPA fraction of Mn (1.2–11 mg kg?1), Zn (0.3–4.4 mg kg?1), Cu (0.3–3 mg kg?1), Cd (0.03–0.09 mg kg?1) observed as a result of the effects of agricultural practices and landscape properties. The values of both total and DTPA-extractable Mn, Zn, and Cu were enriched in the AP horizon probably due to anthropogenic activities particularly successive use of agrochemical compounds and manure during numerous years. Using soil pollution indices [single pollution (PI) and comprehensive pollution (PIN)], the study soils were categorized mainly as low to moderate pollution and Zn was identified as the major element affecting on the yield of these indices.  相似文献   

17.
《Applied Geochemistry》2001,16(11-12):1397-1403
The results from past pollution control practices have shown that environmental quality can not be ensured by simply controlling the concentration of pollutants discharged into it. Instead, it is necessary to control the actual amount of the pollutants formed in the environment. Therefore, the loading capacity of agricultural soil for heavy metals (LCASHM) was introduced. LCASHM is defined as the maximum permitted amount of heavy metals in agricultural soil which preserves the benign cycle of materials in the pedosphere and limits the adverse effects of heavy metals on the biosphere, hydrosphere, atmosphere and lithosphere. LCASHM was found to be affected by many factors such as soil characteristics, indicator organisms, forms and history of pollutants, and a combination of other pollution and environmental factors. The LCASHM value is not fixed but instead encompasses a range. The acceptable LCASHM range in China is 23–37 g/ha/a for Cd, 6750–10,125 g/ha/a for Pb, 687–2812 g/ha/a for Cu and 450–675 g/ha/a for As, respectively. On-going research involving LCASHM should focus on the long-term and multiple-factor effects, and the mechanisms of pollutant reactions in soils. In addition, the practical application of LCASHM should also be stressed.  相似文献   

18.
Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous organic pollutants in urban environments including urban soils. Elevated concentrations of PAHs in urban soils are caused by incomplete combustion of petroleum and coal. This study assesses 16 individual PAH compounds in a total of 112 surficial soil samples. The objective was to assess and compare the levels of contamination as well as examine the main sources of PAHs in four urban agricultural soils using molecular ratios of some specific hydrocarbons. The study showed that PAH levels in soil ranged from 1.23 ng/kg in soil collected from Dzorwulu to 2.95 ng/kg in soil collected from Ghana Broadcasting Cooperation (GBC) vegetable irrigation site. Of the total PAHs, the more water soluble PAHs (2–4 rings), which tend to be concentrated in the vapour phase were found to dominate the soils. The percentage dominance were Dzorwulu (52.8 %), Marine Drive (62.5 %), CSIR (53.2 %) and GBC (49.2 %). However, there were significant levels of the more carcinogenic PAHs (5–6 rings) present with percentages as 47.1, 37.5 46.8 and 50.8 % for Dzorwulu, Marine Drive, CSIR and GBC vegetable irrigation sites, respectively, and therefore, may impact negatively on public health. Based on the classification by the Institute of Soil Science and Plant Cultivation in Pulawy, Poland, urban soils in Accra could be classified as contaminated to different levels. Molecular ratios of Flu/pyr and PA/Ant were calculated to determine the main sources of PAHs. Results showed that PAHs could originate mainly from incomplete combustion of petroleum products, especially from atmospheric fallout from automobile exhausts. The study further showed that B(a)P concentration of 0.05 ng/kg in soil from GBC urban vegetable irrigation site requires immediate clean-up exercise and monitoring to mitigate human health impact.  相似文献   

19.
The aim of the present study was to assess the levels of heavy metal contamination in soils and its effects on human health in the northern Telangana, India. Soil samples were collected randomly from 15 sampling stations located in the northern Telangana and analyzed for arsenic (As), chromium (Cr), copper (Cu), zinc (Zn), nickel (Ni), and lead (Pb). The index of geo-accumulation (Igeo), ecological risk index (ERI), hazard quotient (HQ), hazard index (HI), cancer risk (CR), and lifetime cancer risk (LCR) were used to estimate the heavy metal pollution and its consequence to human health. Results indicated that As, Zn, Cu, Pb, and Ni were within recommended limits, while Cr concentration (60 mg/kg) exceeded the maximum recommended limit in 93% of soil samples. The HI values of Cu, Ni, and Zn were all less than the recommended limit of HI?=?1, indicating that there were no non-carcinogenic risks from these elements for children and adults. LCR for As and Cr concentrations of the soils was found higher than the acceptable threshold value of 1.0E?04, indicating significant carcinogenic risk due to higher concentration of these metals in the soils of the study region. The chronic daily intake of the metals is of major concern as their cumulative effect could result in several health complications of children and adults in the region. Therefore, necessary precautions should be taken to eradicate the health risk in the study region.  相似文献   

20.
Total concentrations of Cd, Cr, Co, Fe, Pb, Ni, Mn and Zn were determined by atomic absorption spectrophotometry in the surface sediments of Taylor Creek, Southern Nigeria. The most concentrated trace metals, ranging from 113.2 to 5160.7 mg/g-dry weights were Fe, Pb, Mn, Ni and Zn. There was no significant variation in sediment-associated metal levels (P>0.05). The metal pollution index was highest at Agbia/Nedugo and is attributed to local contamination of the Creek. The concentrations of low molecular weight polycyclic aromatic hydrocarbons (PAHs) were also detected and quantified in the sediments by capillary gas chromatography equipped with a flame ionization detector. The concentration levels of 178.1-1266.3 mg/g-wet weights were high for the PAHs. The results indicate that the pollutants, which are bio-accumulatable, could contribute to inferior biodiversity, and shifts in community composition from sensitive to tolerant taxa.  相似文献   

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