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Investigations on Mud on Heavy Metal Contaminated Flood-Plain of Tisza
96-101Views:136At the beginning of the year 2000 subsequently to a mine accident high heavy metal content mud entered the catchment area of the Tisza and was transported through the whole Hungarian section of the river. The majority of the heavy metals had been bounded to the floating sediment that was deposited on the flood-plain soil during flood forming a new, 5-10 cm thick layer. In the mud samples collected after the flood there was a clearly visible dark grey layer with significantly higher heavy metal content that was formed by the pollution wave and it was sorruonded by a light layer. The upper layer of flood-plain soils are formed from this mud layer during the soil development process, so the amount of Lakanen-Erviö soluble heavy metals that correlate with bioavailable heavy metal content was examined as well. In this case only the lead content was significantly higher in the dark layer.
New mud samples were collected after the 2001 flood. Separate layers could not have been identified, their colour was similar to those of the previous year’s light layers’. Comparing to this light layer the total Zn and Lakanen-Erivö soluble metal content was significantly lower in the mud samples of the year 2001. While the proportions of total and Lakanen-Erviö soluble metal concentrations were equal in both of the layers regarding the elements, these ratios have significantly changed next year regarding Pb and Zn: the amount of Lakanen-Erviö soluble metals considerably decreased.
As a result of sequential extraction the heavy metal content was rather low in the water soluble and exchangeable and NaOH-soluble fractions, so heavy metals found in the mud could be released in greater amount only in case of a heavy acidification. -
Classification of a diffuse heavy metal polluted mining site using a spectral angle mapper
119-123Views:128Characterization of heavy metal polluted abandoned mining sites is complicated, as the spatial distribution of pollutants often changes dramatically.
In our study, a hyperspectral data analysis of the Gyöngyösoroszi abandoned Pb-Zn mine, located in northern Hungary, where Záray (1991) reported serious heavy metal contamination, was carried out using ENVI 4.3. In this area, galena (PbS), goethite (FeO(OH)), jarosite (KFe3(SO4)2(OH)6), sphalerite ((Zn, Fe)S) and pyrite (FeS2) were the predominant minerals in the alteration zones was chosen as the target mineral.
Spectral angle mapper (SAM) and BandMax classification techniques were applied to obtain rule mineral images. Each pixel in these rule images represents the similarity between the corresponding pixels in the hyperspectral image to a reference spectrum.
As a result of hyperspectral imagery the distribution of pyritic minerals (sphalerite, galena) in the area was defined. Both of the mineral formations occur, especially in mine tailings, the area of the ore preparatory, and the Szárazvölgyi flotation sludge reservoir. According to the results, jarosite and goethite have similar distributions to sphalerite and galena. The results showed that hyperspectral remote sensing is an effective tool for the
characterization of Pb, Zn and Fe containing minerals at the examined polluted sites and for modelling the distribution of heavy metals and minerals in extensive areas.
This classification method is a basis of further detailed investigations, based on field measurements, to map the heavy metal distribution of the studied area and to quantify the environmental risks caused by erosion, which include DEM (digital elevation model) and climatic and hydrological data sources. Furthermore, it can be used primarily to support the potentially applicable phytostabilization technique and to isolate hot spots where only ex-situ remediation techniques can be applied. -
Applicability of hyperspectral technology for in situ phytoremediation
71-78Views:136The characterization of heavy metal polluted abandoned mining sites is a complicated assignment due to the variable spatial distribution of the pollutants, therefore complex integrated method is required in order to assess precisely the amount and the distribution of the contaminants. The examined area is flotation sludge reservoir of abandoned Pb-Zn mining site with serious heavy metal contamination. located in Gyöngyösoroszi, Northern Hungary.
The hyperspectral image of the flotation sludge is obtained by using a Digital Airborne Imaging Spectrometer DAIS 7915, in the frame of DLR HySens first Hungarian hyperspectral flight campaign (21/08/2002). Parallel to the flight campaign heavy metal content of soil samples were examined from the area of the flotation sludge. The analysis of hyperspectral data was verified by the examination of mine tailing samples by FPXRF (Field Portable X-ray Fluorescence spectrometry) (NITON XL-703).
Determinations of heavy metal containing minerals are based on the spectral profiles of the pixels of the area with using USGIS standard spectral profiles of the examined materials (galena, pyrite, sphalerite, goethite and jarosit).Applying the Spectral Angle Mapper with BandMax classification the distribution of minerals (galena, pyrite, sphalerite, goethite, jarosit) in the area was defined. The mineral formation occurs especially at the levees and the barren places of the Szárazvölgyi flotation sludge reservoir. Based on the statistic results of the samples, principal component analysis and correlation coefficient between the different metal content of the samples were calculated. The highest correlations were found between Pb-Zn, Fe-Zn and between Fe-Pb. This prove the results of the principal component analysis, where usually Pb, Zn, Fe introduce the main component.
Canopy analysis was also carried out with the hyperspectal image in order to classify the differences between vegetation types at the Szárazvölgy flotation sludge reservoir and analyse the applicability of it. Supervised classification methods were used to distinguish 8 vegetation types based on the spectral properties of the area. The results of the classifications were compared to a ground truth image, based on ortophoto, topographic map, and GPS based field data collection. According to results of the comparison, the paralellpiped classification method is proved to be appropriate method based on the overall accuracy of canopy classification, which was 54% due to heterogeneity of the vegetation.
The results of hyperspectral data and FPXRF analysis suggest that Pb, Zn and Fe containing minerals have similar spatial distribution in the examined and barren area.
Based on this study hyperspectral remote sensing is likely to be an effective tool for the characterization and modeling the distribution of Pb, Zn and Fe containing minerals at the examined heavy metal polluted sites. Further more, based on the vegetation analysis plant species for phytoremediation can be defined.
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Heavy Metals in Agricultural Soils
85-89Views:82The soil constitutes the basis of the food chain. To keep soil conditions in a good trim is very important, it’s part of the sustainable development and of producing food supply harmless to health.
In some cases, soil productivity is the only important part, qualitative requirements or economical characteristics can improve it. The soil is threatened by two danger factors: the soil degradation and the soil pollution. The accumulation of different harmful and/or toxic substances in the soil is well known. Heavy metals constitute a part of it. Metals in the soil and in the soil-solution are balanced. This balance depends on the type of the metal, on the pH, on the cation-band capacity of the soil, on the redox relations and the concentration of cations in the soil.
To be able to handle the metal contamination of the soil, it is important to estimate the form, the possible extension and the concentration of metals.
Of course, the different types of soils have different physical-chemical, biological and buffer capacity, they can moderate or reinforce the harmful effects of heavy metals. To draw general conclusion of the dispersion and quantitative relations on the metals originated from different contamination sources is hard, because in some emissive sources contamination is limited in small areas but on a high level, some others usually expand on larger areas, and as a result of equal dispersion, the contamination’s level is lower.
Heavy metals – unlike alkali ions – strongly bond to organic materials, or infiltrate in a kelát form. Their outstanding characteristic is the tendency to create metal-complex forms. Kelats take part in the uptaking and transportation of heavy metals. Heavy metals exert their effects mostly as enzyme-activators.
The metals cannot degrade in an organic way, they accumulate in living organisms, and they can form toxic compounds through biochemical reactions.
Lot of the heavy metals accumulate on the boundaries of the abiotic systems (air/soil, water/sediment), when physical or chemical parameters change, and this influences their remobilization.
Human activity plays a great part in heavy metal mobilization, results in the human origin of most biochemical process of metals.
To understand the toxic influence of accumulated metals of high concentration, their transportation from soils to plants or their damage in human health, must clearly defined and investigated.
For effective protection against soil pollution, the types and levels of harmful pollution to soil must identified, regarding legal, technical and soil-science aspects, preferable in a single way. Difficulties in this area mean that toxicity depends on loading, uptake, soil characteristics and living organisms (species, age, condition etc.), furthermore, local and economic conditions considerably differ. -
Potential use of bamboo in the phytoremediation in of heavy metals: A review
91-97Views:357There are many literature sources focusing on the phytoremediation of woody plants, but there are only few dealing with the phytoremediation of bamboo plants. Phytoremediation technology has the advantages of little disturbance to the environment and low remediation cost. Bamboo mainly exists in tropical and subtropical regions. As an energy plant, bamboo has a fast growth cycle, large biomass, simple cultivation, high economic efficiency, and convenient harvesting, which highlights the advantages of bamboo in phytoremediation. In addition, bamboo plants have good tolerance and uptake ability to heavy metals and have high application potential and development value in uptaking heavy metal contaminated soil. However, due to climate, temperature and other reasons, bamboo cannot be widely planted in most countries. Research status of remediation of heavy metal contaminated soil by bamboo plants is summarized. The feasibility of its application in heavy metal contaminated soil is discussed in this paper. Aiming at the shortcomings of existing research, bamboo plants have a prospect in the field of plant phytoremediation for the future.
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The effect of lead and copper heavy metal salts on soil microorganisms under laboratory circumstances
55-59Views:165he population dynamics of calcareous chernozem soils polluted with different concentrations of lead and copper heavy metal saline solutions was examined.
The experiment was carried out in the soil biological laboratory of the Institute of Agricultiral Chemistry and Soil Science at DE AGTC MÉK in 2012. For the determination of the concentration of the undiluted stock solutions we multiplied the smallest toxic concentration values of the MSZ 08-1721/1-86 Hungarian standard by forty. The intermediary concentrations of the treatments were produced with adequate dilution of the stock solutions until a dilution level equal to the values of the standard. The statistical evaluation of the data was performed with ANOVA (Analysis of Variance) including the determination of the standard deviation and significant difference. Investigating the effects of the different treatments on the soil microbes we established that both heavy metal saline solutions had a negative effect on the population dynamics of bacteria and microscopic fungi living in the soils. The negative effect of copper – as a potential toxic micro nutrient – turned out to be less strong than the negative effect of the toxic lead. According to our results the correction of the treatment levels is recommended in order to further tolerance examinations and the determination of the tolerance levels.
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Spatial Relationships Between pH and Vegetation Pattern in an Area Contaminated with Heavy Metals
140-143Views:102It is not possible to gain information on the risk factor representing the bioavailability and the mobility of the contaminants only on the basis of their total concentrations. Especially, in case of heavy metals, which can be charaterised with very different chemical forms and their mobil and mobilizable parts are determined by complex balances highly sensitive to the changing environmental conditions. Considering mine tailings, however, the toxic elements are basically in ore forms having low adsorption capacity, thus the heavy metal ion concentration in solution is governed mainly by the pH conditions. In Gyöngyösoroszi, the spatial distribution of the total heavy metal concentrations as well as that of pH values determining the bioavailable part of the toxic elements were estimated and by mapping the vegetation pattern, relationship was analysed among the total Zn, Cu, Pb and As concentrations, the pH and the species present. Results show that the presence of the certain plant species is highly determined by the pH on the mine tailing material, the highest vegetation density was found where the bioavailability of the toxic elements were considered the smallest as a result of the neutral pH. As a result, high diversity could be found even in places where the total zinc, copper, lead and arsenic concentrations were extreme. In addition, plant species could be identified, which are tolerant to toxic elements and present even if the pH is low and the bioavailable part of the heavy metals is relatively high.
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Plant production possibilities on a heavy metal contaminated soil with the purpose of biorefinery
215-222Views:126Significant part of not cultivated area of Hungary is not suitable for agricultural utilization because of industrial
pollution. Technologies of biorefinery make reutilization of contaminated areas possible. Biomass of plants
produced on polluted soils can be raw material of valuable products. Applicability of biorefinery was tested on a
heavy metal polluted soil, where the contamination originated from previous mining activity. Complete biomass
utilization was aimed to obtain cosmetic ingredients, pharmaceutical agents, and precursors. During our research
work 88 plant species and varieties were produced and tested for potential utilizable components. Levels of
possible contaminants in these plants were monitored, and amounts of carbohydrates, protein, organic acid and
cellulose were determined as well. Different plant extracts were tested as potential sources of biologically effective
components or as raw materials for lactic acid fermentation. Our results show that biorefinery is a real possibility
for utilization of polluted areas. Numerous plants could be cultivated on contaminated areas without increased
levels of contaminants in their tissues, thus they can be sources of valuable compounds. -
Examination of the Binding Forms of Cu, Zn, Pb and Cd
161-165Views:35Cu, Zn, Pb and Cd binding forms were examined on brown forest soil with clay illuviation, on clcareous chernozem and on meadow soil type. We applied one metal ion and the mixture of all at two different concentrations on the soils. Our results show all the four metal ions significantly bound to the mobile fraction on brown forest soils, while on calcareous chernozem and on meadow soil type they were mainly in other fractions. The higher heavy metal load and the presence of other metal ions increased the ratio of the mobile binding form.
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Examination of the possible role of biofertilizers and wood ash in the nutrient supply of plants
87-95Views:98Some physiological effects of bacteria containing fertilizer and some wood ash were examined in the experiments. The minimization of the use of chemicals in agriculture has been an ongoing challenge. One option lies in the intenzification of soil life. The release of organic matters by the roots and bacteria play a significant role in the uptake of minerals. The main problem to usilize wood ash in agriculture is its heavy metal contents. The solubility of heavy metals is very low, therefore there is no risk to use the wood ash in the agriculture and in the horticulture according to our experiments. The wood ash and biofertilizer contains several micronutrients in an optimum composition for forestry and agricultural plants.
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Food safety of plant origin food
161-164Views:201Expectation regarding changes related to food production, transportation, distribution and marketing have changed considerably in several regions of the world over the past decades. It is especially true for highly industrialized countries where not only the food security is important but the food safety is essential too. The concentration of production – processing – distribution involves the danger on the one hand products of unsuitable quality from point of view of nutritional physiology and the other hand ones that may contain substances harmful to human health will become widespread among consumers. We investigated the heavy metal, pesticide remains and mycotoxin content of different plant products.
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The special questions of nutrition of forest plants
83-88Views:69Some physiological effects of bacteria containing fertilizer and some wood ash were examined in the experiments. The minimization of the use of chemicals in agriculture has been an ongoing challenge. One option lies in the intenzification of soil life. The release of organic matters by the roots and bacteria play a significant role in the uptake of minerals. The main problem to usilize wood ash in agriculture is its heavy metal contents. The
solubility of heavy metals is very low, therefore there is no risk to use the wood ash in the agriculture and in the horticulture according to our experiments. The wood ash and biofertilizer contains several micronutrients in an optimum composition for forestry and agricultural plants. -
New methods of compost homogeneity determination in sewage sludge based compost prisms
49-52Views:183There is no effective method of homogeneity measurement of compost prism. The most frequently used technology is the examination of the particle distribution. This method needs a lot of time and large number of samples. The aim of our research is establishing different effective methods to determine the homogeneity of compost prisms. During our work, we examined the homogeneity of a prism made of sewage sludge and saw-dust mixture.
The measurements were based on the different properties of raw materials. According to this we examined the homogeneity by moisture content, heavy metal content and gas distribution measurements.
The most effective method is the measurement of gasconcentration. Although gas-concentration measurements it need special equipment it has more advantages than the other methods. The examination of gas-distribution compensates the problem of sampling because the measurement is direct. It provides the opportunity to estimate the amount of emitted toxic gases and to determine the maturity of the compost and the effectiveness of the degradation. -
Effect of cadmium and zinc contamination on the population dynamics of soil microorgani
73-77Views:124Changes in the population dynamics of microorganisms in a soil artificially contaminated with various doses of cadmium and zinc was examined from a quantitative point of view, under laboratory circumstances. The research was based on a chernozem soil originating from the area of a long-term microelement contamination model experiment (Nagyhörcsökpuszta, Hungary), which was carried out during 1991 in the Experimental Site of the Institute of Soil Science and Agricultural Chemistry, Centre for Agricultural Researche Hungarian Academy of Sciences, Budapest, Hungary. According to the amount of bacteria, microscopic fungi and nitrifying bacteria, it can be stated that the effect of contamination can be observed even in the perspective of nearly two decades. In more cases significant changes in the number of soil bacteria and microscopic fungi could be observed, and the nitrification activity increased in case of both microelements. Therefore the further research of changes in microbial activity of these soils can provide novel scientific results.