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1.
U. Meier 《洁净——土壤、空气、水》1990,18(1):111-114
The adsorption/desorption ratio is an important quantity of the displacement of heavy metals in the soil. Adsorption isotherms as controlled quantities are suitable for the development of a transport model. With the aid of the T value the sorption coefficients and distribution quotients can be determined for different soils. By two examples of simulation the migrations of Cd and Pb were calculated with soil samples of warp clay/gley and loam/para-brown earth. It was found, inter alia, that with increasing time of input the concentration of dissolved and adsorbed heavy metals grows and that the added heavy-metal ions are absorbed in the uppermost layers already. For cases of continuous input the simulation model is recommended for the practice to estimate the migration of heavy metals in soils. 相似文献
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3.
New aspects on the chemistry of aluminum in soils 总被引：2，自引：0，他引：2
Gerhard Furrer 《Aquatic Sciences - Research Across Boundaries》1993,55(4):281-290
Dissolution kinetics of minerals can be significantly inhibited by re-adsorbed aluminum. As a consequence of neutralization, polynuclear Al species may be formed in soil solutions. While re-acidification leads to decomposition of the polymers, further neutralization induces the formation of aggregates. The complexation of heavy metal ions with dissolved and aggregated Al polymers is illustrated as a potential factor influencing the chemical speciation of heavy metals in soils. 相似文献
4.
Ahmed A. Abdelhafez Hassan H. Abbas Rafat S. Abd‐El‐Aal Nabil F. Kandil Jianhua Li Wahballah Mahmoud 《洁净——土壤、空气、水》2012,40(4):356-363
Excessive amounts of mineral fertilizers are unnecessarily applied to agricultural soils in Egypt to increase crop yield. The current study aims at assessing the impacts of fertilization with different mineral fertilizers for different cultivation periods on the accumulation of heavy metals in soils and plants grown thereon. In addition, human risks resulted due to the exposure to these metal ions through ingestion, and dermal routes were evaluated. Soil and plant samples were collected from several locations in El‐Behira Governorate, Egypt and their heavy metal contents were measured. The result indicated that there is a continuous accumulation of heavy metals in the soils and the plants grown thereon. Calculation of the hazard index (HI) revealed that humans, especially children, have a potential health risk for both Pb and Cd, which have levels greater than the safe level (1). Finally, the obtained results showed that the continuous application of mineral fertilizers containing high levels of heavy metals pose a potential health threat. 相似文献
5.
A screening method for heavy metals in aqueous extracts of soil is presented which is based on inhibition of the enzymes urease and alcohol dehydrogenase. The method is suitable to detect cupric and mercury ions in concentrations below 0.01 mg/L and several other heavy metal ions in 1000 fold higher concentration. It is shown that the test may be used for screening of mercury ion concentrations exceeding 0.03 mg/L in aqueous solution when copper chelators are added to the test system. The usefulness of the presented tests to detect heavy metals eluted from soil was verified with samples from ore mining waste. The concentration of copper, lead, and zinc eluted from these samples to different amount was determined by atomic absorption spectrometry and was in good agreement with the enzyme inhibition data obtained with these samples. 相似文献
6.
The effect of land reclamation on the migration and accumulation of heavy metals and some pollutants in small rivers is determined. The study was conducted in the Middle Amur lowland in different phases of hydrological regime and at different extent of floodplain inundation. The formation of the hydrological regime in small rivers in this area is governed by the irregular annual runoff distribution. The seasonal character of flood periods requires water samples to be taken before spring flood (April) and after floods have passed (September–October), and at various extent of floodplain inundation. The field studies of water-courses were carried out in 2009–2014. The water samples were analyzed to determine the concentrations of heavy metals (iron, manganese, copper, nickel, cobalt, lead and zinc), suspended substances, organic carbon (total, dissolved, and suspended), humic and fulvic acids, and volatile organic compounds. The mobility of heavy metals in surface watercourses was shown to reflect the effect of drainage and surface runoff from soil horizons, an increase in the concentrations of suspended and organic compounds, especially, fulvic acids, which enhance their geochemical mobility. During floods, an increase in heavy metals washout from floodplain soils and the dilution of their concentrations causes the formation of a single-type concentration series of heavy metals. In addition, the processes of pollutants migration show an effect of changes in the geomorphological characteristics of floodplain–channel complexes and a decrease in flow velocity in watercourses in the areas where land reclamation was applied. Thus, all factors mentioned above lead to a decrease in water pollution index in the river. 相似文献
7.
The results of monitoring performed by Southern Research Institute of Marine Fisheries and Oceanography (YugNIRO) in 1990–1998 in the course of dredging operations with dumping in the Black Sea of soils dredged in Kerch Strait are analyzed. The study covered the soil physical properties and particle size distribution; the extent of the soil pollution by heavy metals, oil products, and organochlorine compounds; the amounts of such pollutants delivered into the sea with these soils; the extent of pollution of water and bottom sediment in the zone of soil dumping offshore Kerch Strait. The amounts of pollutants entering the Black Sea as a result of soil dumping are compared with those entering the sea from other pollutant sources, and the extent of environmental pollution in the dumping zone is compared with the background level of the sea pollution. The admissible rates of soil dumping are estimated, and potential consequences of this process are predicted. 相似文献
8.
Gladyshev M. I. Gribovskaya I. V. Ivanova E. A. Moskvichova A. V. Muchkina E. Ya. Chuprov S. M. 《Water Resources》2001,28(3):288-296
Data of two field studies were used to analyze the concentrations of Na, K, Ca, Mg, Fe, Mn, Zn, Cu, Al, Cr, Ni, Cd, and Pb in the water, bottom deposits, zoobenthos, fish, and macrophytes of the Pond Bugach and in the soils near the pond. It was established that the majority of metals in the soils and bottom deposits correlate and their concentrations are governed by the universal geochemical factors of the region. The heavy metals were recognized that originate from anthropogenic sources and their concentrations were found to exceed the maximum admissible values for different components of the ecosystem. Five types of heavy metals migration were recognized in the soil–bottom deposits–zoobenthos–fish chain and in macrophytes. Statistically significant difference was found to exist between the concentrations of some heavy metals in the muscles of fish species with different food types (crucian carp and perch) as well as between the correlations of metals. The recorded concentrations were compared with the concentrations of metals measured in the last decade in other limnetic ecosystems in Siberia, Europe, North America, and China. 相似文献
9.
Magnetic susceptibility is a non‐conventional way that can be used for evaluating proxy soil heavy metals pollution. The paper monitors available heavy metals (Cu, Fe, Zn, and Mn) present in cultivated soils around iron–steel plant by soil magnetic susceptibility. Our study was located in an area with high pollution with small grid density of 250 m in China. Results showed that low field magnetic susceptibility was significantly correlated with available Cu, Zn, and Mn. No clear association exists between magnetic susceptibility and available Fe, soil organic matter, pH. Frequency dependent susceptibility >5% suggests the possible presence of super‐paramagnetic particles, fly ashes produced during coal combustion. 相似文献
10.
Application of Superabsorbent Polymers for Improving the Ecological Chemistry of Degraded or Polluted Lands 总被引：3，自引：0，他引：3
About 3.5 billion ha of land, which amounts to almost 30% of the total solid land of the world, has been degraded by human activities. The ecological restoration of these lands is a major challenge for mankind since they are the only option left for increasing the amount of arable land and producing food for the ever growing worldwide population. One common feature of these degraded lands is the fact that their organic soil matter is degraded also. Rainfall therefore, changes from a blessing to a menace since it is not kept in the soil and therefore causes erosion. A solution for the restoration of these lands could be the application of superabsorbent polymers (SAPs) to these soils. These substances are like ‘artificial humus’ as they are hydrophilic and contain carboxylic groups. This enables them to bind cations and water. They have the following advantages for the restoration of degraded lands. They increase the plant available water in the soil which enables the plants to survive longer under water stress. SAP amendment to soils reduces the evapotranspiration rate of the plants. They induce a significantly higher growth rate in plants growing on SAP amended soil. They bind heavy metals and mitigate their action on plants. They mitigate the effects of salinity. The benefits of SAP amendment to soils substantially outweigh their costs. 相似文献
11.
This investigation had the purpose of evaluating the reliability of a sequential extraction procedure according to Zeien and Brümmer (1989) which is performed routinely to analyse the distribution of heavy metals to different soil phases. Reliability was tested by two hypotheses. According to the first hypothesis an error propagation increased during a morefold extraction of heavy metals from a single soil sample to such an extend that it does not allow a statistical comparison of different analyses. This assumption was confirmed in an interlaboratory study of five participants applying the sequential extraction scheme on two different soils. The heavy metal amounts extracted by the different partners were of the same magnitude, but from the results no statistical correspondence at the 95% confidence level could be observed. The second hypothesis stated that also weak extraction agents were able to release metals from the more immobile soil fractions, especially if the amount of easily soluble metals was comparatively small. To answer this question the sequential extraction was modified by carrying out selected weak extraction steps several times. As expected the intensified extraction conditions caused a decrease of the element content within the more resistant phases. However, the additional release in the first four extraction steps of Pb, Mn, Fe, and Zn was only in the range of 5 to 10%. Furthermore, it was observed that a single EDTA extraction (step four within the sequential extraction scheme) was capable to extract the same amount of metals as the first four extraction steps of the original scheme at a variation of about 15%. From these results it was concluded that the EDTA step alone already represents a reliable pool of mobilisable metals. Thus it can be maintained that such a simple single EDTA extraction can be used to assess the environmental risk from heavy metal contaminated soils or to predict the potential heavy metal release of soil remediation processes. 相似文献
12.
Ecological risk assessment of Cd and other heavy metals in soil-rice system in the karst areas with high geochemical background of Guangxi,China 总被引：1，自引：0，他引：1
《中国科学:地球科学(英文版)》2021,(7)
Karst areas are widely distributed in China, and the soil derived in these areas is enriched with trace elements and has the typical characteristics of high geochemical background. Therefore, soil ecological risk has gradually attracted extensive attention. In this study, 1090 sets of rice grains and paired rhizosphere soils were collected as research objects from the outcropped karst areas of carbonate rocks in Guangxi, and the concentration characteristics and influencing factors of heavy metals, such as Cd and As, in rice grains and the corresponding soils were studied. According to the Chinese Soil Environmental Quality Standard(GB 15618-2018), the proportion of karstic soil samples in Guangxi with heavy metal(As, Cd, Cr, Cu, Hg, Ni,Pb and Zn) concentrations that exceed the standard risk screening values was generally greater than that of surface soils in China or non-karstic soils in Guangxi. Notably, Cd and As were the most prominently enriched heavy metals in soils. According to the Chinese Food Safety Standard(GB 2762-2017), Pb in rice grains from the studied area did not exceed the standard; the exceedance rates of Cr, Hg, and inorganic As were only about 1%; and the exceedance rate of Cd was 12.5%. Soil Cd concentration increased gradually whereas the concentration and exceedance rate of Cd in rice grains decreased gradually with the increase of soil pH. Specifically, the exceedance rate of Cd in rice grains was only 4% when soil pH6.5. The results indicated that the risk screening values of Cd element in the Chinese Soil Environmental Quality Standard are not satisfactorily applicable to the ecological risk assessment of Cd in karstic soils. Therefore, the recommended threshold values for the safe utilization and risk control of Cd in karstic soils was proposed so as to provide a basis for soil environmental quality hierarchization, pollution risk control and land safety zoning of agricultural land in karst areas in China. 相似文献
13.
With the aid of the Soviet atomic-absorption two-channel spectrometer “Saturn” successful attempts were made to improve the sensitivity of the heavy-metal determination after the previous two-step separation and concentration technique. Compared with other combustible gases, the propane/nitrogen-oxide flame is preferred. Because of the possibility of the direct determination of the heavy metals in the water samples the duration of analyses could be reduced by fifty per cent. Besides the heavy-metal analytics, a rapid-determination technique for calcium and magnesium was developed. The results of the different determination techniques and the ranges of measurement are given in several tables. 相似文献
14.
Contamination characteristics of heavy metals in wetland soils along a tidal ditch of the Yellow River Estuary, China 总被引：3，自引：0，他引：3
Junhong Bai Laibin Huang Denghua Yan Qinggai Wang Haifeng Gao Rong Xiao Chen Huang 《Stochastic Environmental Research and Risk Assessment (SERRA)》2011,25(5):671-676
Surface soils (0–20 cm) were collected from along a tidal ditch of the Yellow River Estuary in August of 2007. Samples were
subjected to a total digestion technique before they were analyzed for total concentrations of As, Cr, Cd, Cu, Ni, Pb, Zn,
P and S in order to investigate heavy metal contamination levels in wetland soils nearby the tidal ditches and their main
sources. Results showed that the mean concentrations of these heavy metals except for As and Cd were lower than the Class
I criteria. Nearly all sampling sites showed lower contamination levels for As and Cd, while no contamination levels for other
heavy metals. Cr, Cu, and Ni mainly originated from parent rocks, and Pb and As might originate from tidal seawater and oil
field pollution, respectively; while Cd and Zn mainly originated from parent rocks and tidal seawater. Most of heavy metals
showed significant correlations with total concentrations of P and S, however, no significant correlations were observed between
them and soil pH, slat and soil organic matter. 相似文献
15.
Soil quality is more difficult to define than air and water quality but it has an impact especially on the latter. The export of soil-based nutrients to waters is of increasing concern. Policy aiming at preservation of soil quality can be either effect-orientated or source-orientated. Statutory measures for soil protection in the Netherlands originate from the Soil Protection Act (SPA), which came into force in January, 1987. The SPA still is a framework law which provides very general regulations only. Practical implementation is achieved by means of General Administrative Orders (GAO). The law offers a framework for measures and regulations to protect the properties of soil which constitute the conditions for proper soil functioning. The first GAO introduced was the ‘Decree on use of animal manure’, which became operational on 1 April 1987. During recent decades there has been a large increase of intensive animal husbandry in the Netherlands. This development led to a strong imbalance between minerals imported in the country in the form of feed and raw materials for feed production, and minerals exported by dairy and animal products. The minerals produced in manure and animal slurries are far exceeding the amounts needed for proper crop fertilization. Standards for the use of animal manure are based on the phosphate content but this results in the application of unacceptable amounts of nitrogen and heavy metals. Phosphate saturation of soil was safeguarded by introducing special regulations for P-saturated soils. However, this has not been successful on judicial basis, indicating the need for general environmental protection legislation, instead of the compartmental (air-water-soil) approach. 相似文献
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Located in Liaoning Province, one of the traditional heavy industrial areas in China, Dahuofang Reservoir provides drinking water for nearly 30 000 000 citizens, as well as industrial and agricultural water for dozens of several cities and rural areas. The distribution of hazardous heavy metals is described in several types of soil, crops, and in different industrial or mining areas and main sewage irrigation areas. Five possible reasons that may cause the pollution are analyzed and listed. Also we provide some pragmatic suggestions for the remediation of heavy metals in contaminated soils. 相似文献
18.
Sorption of Heavy Metals from Acetic Acid Extracts by Ferric Phosphate Colloids A conceivable procedure to remedy heavy metal contaminated soil materials is given with extraction of organic acids, i. e. by the use of a biological degradable extraction agent. The following concentration step of heavy metal extracts should be carried out to a great extent without a change of the low pH values. A conventional precipitation of the heavy metals by rising the pH should be avoided in order to introduce no large amounts of salts into the wastewaters of the process and furthermore, to reduce the amount of sludge to be deposited. The process scheme developed with the objective of heavy metals recycling consists of the following steps: the extraction of the heavy metal contaminated soils with weak organic acids like acetic acid or citric acid, the electrolysis of the extract, and a concentration step in order to treat metal concentrations not fully removed by electrolysis. This third step, e.g. could contain sorption on iron phosphate colloids and precipitation within the acidic environment. It has been examined whether a removal of the heavy metals Pb, Cd, Cu, Sb, Cr, Ni and Zn from acetic aqueous solutions of pH between 2 and 3 can be carried out. 相似文献
19.
Masayuki Sakakibara Yuko Ohmori Nguyen Thi Hoang Ha Sakae Sano Koichiro Sera 《洁净——土壤、空气、水》2011,39(8):735-741
Phytoremediation is an environmental remediation technique that takes advantage of plant physiology and metabolism. The unique property of heavy metal hyperaccumulation by the macrophyte Eleocharis acicularis is of great significance in the phytoremediation of water and sediments contaminated by heavy metals at mine sites. In this study, a field cultivation experiment was performed to examine the applicability of E. acicularis to the remediation of water contaminated by heavy metals. The highest concentrations of heavy metals in the shoots of E. acicularis were 20 200 mg Cu/kg, 14 200 mg Zn/kg, 1740 mg As/kg, 894 mg Pb/kg, and 239 mg Cd/kg. The concentrations of Cu, Zn, As, Cd, and Pb in the shoots correlate with their concentrations in the soil in a log‐linear fashion. The bioconcentration factor for these elements decreases log‐linearly with increasing concentration in the soil. The results indicate the ability of E. acicularis to hyperaccumulate Cu, Zn, As, and Cd under natural conditions, making it a good candidate species for the phytoremediation of water contaminated by heavy metals. 相似文献
20.
Effects of Wastewater-borne Heavy Metals on Mangrove Plants and Soil Microbial Activities 总被引：11，自引：0，他引：11
Effects of wastewater-borne heavy metals on growth of young plants (9-month-old Bruguiera gymnorrhiza) and soil microbial activities in mangrove microcosms were evaluated. During the 26-week loading period, each mangrove microcosm received 31.2 litres synthetic wastewater of three strengths: normal, medium (5 times of normal strength) and strong (10 times of normal strength). Normal strength wastewater had Cu, Zn, Cd, Cr and Ni concentrations of 3, 5, 0.2, 2 and 3 mg l−1, respectively. Plant growth and total plant biomass in wastewater-treated microcosms were lower than that in the control, and the maximum reduction was found in microcosms receiving strong wastewater. Alkaline phosphatase activity and ATP contents of the mangrove soils receiving wastewater were also reduced. More than 95% reduction in these two parameters was found in soils loaded with strong wastewater. Microtox test demonstrated that soil elutriates obtained from microcosms receiving strong wastewater were of the greatest toxicity (EC50 was 23%). These results show that high concentrations of heavy metals present in strong wastewater were toxic and posed negative effects to both mangrove plants and soil microbial activities. Microbial activities were generally more sensitive to the toxicity of heavy metals than plants. 相似文献