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Classification of a diffuse heavy metal polluted mining site using a spectral angle mapper
119-123Views:85Characterization 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. -
Correlations Between the Crown Sizes, Pruning Times and Fruit Quality of Sour Cherry Cultivars
90-94Views:156To increase the intensiveness of sour cherry production, i.e. the use of smaller trees, it is necessary to adopt growth-moderating techniques rather than using dwarfing rootstocks. Apart from the traditional technique of using rootstocks that support stronger growth, new or rarely-used techniques and methods must be adopted. Pruning should be carried out in the summer rather than in the winter, the optimal period being 1-3 weeks after harvest.
A combination of the increase in favourable exposure-time and smaller crown sizes make higher tree densities (tree/ha) and better utilisation of the crown (specific cropload) possible.
The systematic use of summer pruning leads to better quality fruit. -
Fruit melanotic ringspot (FMRS) – a disease of resistant Capsicum genotypes infected with Tomato spotted wilt virus (TSWV) on the fruits
64-69Views:64Etiology of pepper fruit melanotic ringspot (FMRS) disease (Salamon, 2009) was studied on fruit samples collected in forced pepper populations. It was noticed that in spite of heavy thrips (Frankliniella occidentalis) infestations and of TSWV epidemy detected in the forcing houses, FMRS occurred only in plants having healthy foliage. Symptomatological surveys strongly suggested that FMRS appeared exclusively in specific pepper genotypes. The size of melanotic ringspots has been observed to grow at room temperature during postripening of diseased fruits. A mechanically transmitted plant virus was isolated from symptomatic parts of 9 white pepper fruits affected by FMRS. On test plants each of the virus isolates caused systemic symptoms characteristic to TSWV. Using cDNA/PCR technique and TSWV N-gene specific primers a ca. 300 bp long DNA fragment has been amplified from total nucleic acid extracted from symptomatic tissues but never from asymptomatic parts of the fruits showing FMRS. Plant progenies grown from seeds of FMRS diseased fruits segregated in respect of resistance and/or susceptibility to TSWV infection. TSWV was also detected in and isolated from three fruits showed non-melanotic yellow rings (one of them was infected with a tobamovirus, too). Seedlings derived from these fruits proved to be susceptible to TSWV. Based on the above results we could conclude that the FMRS disease developed on fruits of “cecei” type white peppers that carry a TSWV resistance gene, most likely the Tsw gene in heterozygous form. These fruits were infected with thrips transmitted TSWV and FRMS appeared as a hypersentive reaction (HR) manifested in fruits.
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Comparison of the technological background of aquaponic systems
47-52Views:260Aquaponics is the combined culture of fish and plants in recirculating aquaculture systems, an ecologically sustainable horticultural production technique with long traditions.
The objective of this study is to compare flood-and- drain, and the water crossflow system and examine the differences in the water quality, fish yield and plant growth parameters for Common carp (Cyprinus carpio) and basil (Ocimum basilicum). During the study, water quality parameters of two treatments were compared in temperatures, pH, EC and NO3¯N were significantly different (p <0.05). Leaf area of the basil plants grew to an average of 20.37 cm2 (± 9.02 cm2). The plants’ biomass production was significantly different (p< 0.05) in the two systems. The biomass production showed lower yield, 458.22 g (± 214.59 g) in the constant flow system that in the flood- and- drain system 692.9 g (± 175.82 g). Fish Growth parameters were better in constant flow system (FCR 5.48 g/g ± 0.19). However, the specific growth rate (SGR) demonstrated that fish grew faster in flood- and- drain system 1.38 %/day (± 0.29).
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Investigation of Salix alba and Populus tremula leaf litter decomposition in the area of Lake Balaton and Kis-Balaton Wetland
159-162Views:160Plant litter decomposition in inland waters contributes significantly to nutrient load, particularly in still waters, such as shallow lakes and wetlands. The decomposition rates of Salix alba and Populus tremula leaf litter was examined in Lake Balaton and Kis-Balaton Wetland, using litter bag technique. Leaf litter was incubated in small (ᴓ=3 mm) and large (ᴓ=900 μm) mesh size bags for the assessment of the relative contribution of macroinvertebrates to leaf litter decomposition. Dry mass, exponential decay coefficient and chemical parameters of water (pH, conductivity, NH4 +, NO3 -, SO4 2-, PO4 3-, Cl-) were determined. Leaf mass loss showed negative exponential pattern during the 168 days of the decomposition period. Leaf litter mass loss generally did not differ between the small and large mesh sizes, suggesting that macroinvertebrates generally have a negligible role in leaf decomposition in the winter period.
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Examination of repeatability of ultrasound scanning technique in young bulls
43-48Views:108The author’s goal with the methodology examination was to determine repeatability of taking and evaluating ultrasound images. In the trial an operator person took two images about the ribeye area and rump fat thickness (P8) of every young bull, which were measured by the same person in four repetitions. Also, we had altogether eight images about the same part of the body. Images were collected using Falco 100 (Pie Medical) real-time ultrasonic scanner equipped with an ASP 3,5 MHz, 18 cm linear array transducer.
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Development of seed analyses by means of various matrix solutions and the MALDI-TOF MS technique
53-57Views:273The earth's population is growing steadily, currently accounting for about 7.3 billion people. Population growth causes food demand to rise, approximately 36 million people die each year due to starvation or related diseases. One solution to this problem is the continuous examination and development of the agricultural economy. In this study, matrix-assisted laser desorption/ionization time-of-flight mass spectrometer (MALDI -TOF MS) were used to analyse of sunflower, soybean and hemp. In order to analyse the protein of maize, this method has already been applied. However, for sunflower, soy and hemp, it is necessary to develop a sample preparation method. Choosing the optimal matrix solution for ionization the traget molecule is an essential part of developing the method. Our aim is to compare two different matrix solutions (α-HCCA, SA matrix), based on the properties (intensity, noise ratio, value of spectra) of the spectra.
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Studies on the Fusarium stalk rot infection of the maize genotypes using the Findex percentage and a computerised image analysis program
45-51Views:96In a continental climate, the pathogens causing the most serious problems are species belonging to the Fusarium genus. When the pathogen attacks the stalk, the plant dies earlier, reducing grain filling and resulting in small, light ears. In addition, the stalks break or lodge, resulting in further yield losses from ears that cannot be harvested. During the three years of the experiment, 14 inbred lines were examined. The genotypes were sown in a two-factor split-plot design with four replications, with the genotypes in the main plots and four treatments in the subplots: two Fusarium graminearum isolates (1. FG36, 2. FGH4), 3. sterile kernels, 4. untreated control. The results experiments showed significant differences between the genotypes for resistance to fusarium stalk rot. Among the inbred lines the best resistance to fusarium stalk rot was exhibited by P06 and P07, both of which were related to ISSS. The precision and sensitivity of disease evaluations carried out visually and using image analysis software were compared in the experiment, and with two exceptions the CV values were lower for the image analysis. As the CV for measurements can be considered as a relative error, it can be stated that image analysis is the more precise of the two methods, so this technique gives a more accurate picture of the extent of stalk rot. The extent of stalk rot developing in response to natural infection is extremely environment-dependent, so the use of artificial inoculation is recommended for selection trials.
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Comparative studies to model bioavailability of pesticides in distinctive soil types
17-23Views:81Bioavailability of pesticides is determined by two major factors: soil characteristics and pesticides’ chemical feature. These factors result in a definite adsorption capability whose extent varies on a large scale. By revealing interactions between pesticides and soils it is of high interest to model bioavailability of widely used pesticides, as it is a key element in terms of prospective toxicological aspects. Our work signifies steps forward improving pesticide soil mobility prediction models as we created model systems representing correctly natural relations. Comparison of different solvent extraction methods proved to be an efficient tool to gain information on the bioavailability of some widely used pesticides as well as to model actual environmental processes.
Comprehensive comparison has been made between different experimental methods by applying 5 extraction models showing diverse efficiency in extracting capability of pesticides. In some cases chloroform excelled in mobilizing pesticides from soil, however mostly application of humic acid solution as extraction model was found to be at least as efficient as methanol, chloroform or CaCl2-solution.
Four chemically much different pesticide (simazine, acetochlor, chlorpyrifos and diuron) were applied to two soil types (both sandy and brown forest). The extracted amounts were determined by GC/MS technique. Adsorption coefficients (Kd) were also calculated for the examined samples.
Obtained results for Kd indicated that chemical feature of pesticides seemed to be of utmost importance in terms of soil binding capability preceding the relevance of soil characteristics. Adsorption capability of chlorpyrifos proved to be the most pronounced preceding simazine and the least prone to bind to soil acetochlor and diuron -
Comparison of sample preparation methods for the identification of Staphylococcus Aureus by MALDI-FOF MS
9-14Views:267Coagulase-positive staphylococci include 3 species, Staphylococcus aureus, S. hyicus and S. intermedius. Of these three species, S. aureus is the most well-known human pathogen. S. aureus is part of the human and animal normal microbiota, however, it is capable of producing several staphylococcal enterotoxins (SEs) that cause intoxication symptoms of varying intensity in humans after consuming contaminated food. Selective media which are used for the determination of coagulase-positive staphylococci from foods are not able to identify isolates at a species. With the MALDI-TOF MS technique, we can identify S. aureus cheaper and faster than by using molecular methods. This paper describes the results of the study of the presence of coagulase-positive staphylococci and S. aureus in many food products, and the application of three sample preparation methods: direct sample preparation, formic acid suspension and ethanol extraction.
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Cluster, a potential tool for rural development
195-201Views:143There was a heavy change in the characteristics of the agriculture in the last 20 years. It become a multifunctional, sustainable, organic system, which needs strategic approach. On the problem map of the hungarian agriculture the most importatnt questions are the following: dual charachter of the land structure, to occidentalize the farm structure. To develop the rural areas we need to real markets needs adapted, competitive, local agricultural production. From the ’90s into Europe’s economic development policies integrated the clusters, this research tries to certify, that this system is viable in classic agriculture and able to dissolve the defecinces, to support the aims of rural development.
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Interaction of yield stability and year in major agricultural crops
41-46Views:85The effect of hydro-meteorological extremities on plant cultivation is the result of the correlation of many factors. These may increase or decrease the effects of hydro-meteorological extremes. The degree of this variance depends on the professionality of treatments, on the quality of the applied technique and technology and also on the soil’s water management characteristics.
The water management characteristics of Hungary’s arable land are mainly unfavorable or medium. In the past two decades the conditions of originally good soils, from a water management aspect, have significantly deteriorated in the critical 0-60 cm soil layer. This is mainly due to unprofessional land use, a lack of deepening cultivation and neglected organic cultivation. At the same time, hydro-meteorological extremities occur more frequently and the sensibility of plant cultivation has increased.
The sensibility of plant cultivation is type and location specific, yet, it also effects both the quality and quantity of the result.
The stability analysis, which covered the period of four decades and incorporated 6-7 agro-ecological areas proves and highlights the following:
• Winter wheat only reacted to extensive cultivation and unfavorable environmental conditions to a small degree. On the other hand, the effect of hydro-meteorological extremities increases.
• The stability analysis of maize, which is sensitive to cultivation technology and the location of cultivation, proved just the opposite. Good soil and adequate technology significantly reduces the effect of any particular year.
• From the years examined, the most favorable proved to be the one with average precipitation. Maize reacted to both extremities in a similar way. Winter wheat reacted to more precipitation with less yield.
• The yield quality of winter wheat was negatively effected by drought. The negative effect of precipitation is limited to the period of ripening and harvest, so the likelihood of such an effect is not significant.
• The yield of sunflower – due to pests – significantly reduces in years with high precipitation, while a difference between dry and average years cannot be pinpointed out. The oil content in both dry years and in years with high precipitation is evident, compared to years with average precipitation.
• The root yield of sugar beet is reduced by drought while the sugar content depends on soil characteristics and climatic extremities. A difference could also be noted by location, whether in Western Hungary and on the Great Plain. Great sugar content can be achieved in years with high precipitation in Western Hungary, while the same result occurred with average precipitation on the Great Plain. Drought did not have a positive effect on sugar content in either location. -
GC-MS studies to map mechanistic aspects of photolytic decomposition of pesticides
11-16Views:78Transformation of pesticides in the environment is a highly complex process affected by different factors. Both biological and physical-chemical factors may play a role in the degradation, whose ratio depends on the actual environmental conditions.
Our study aims to reveal specific details of photolytic degradation of pesticides as important soil contaminants. Significance of these studies is enhanced by the fact that pesticide decomposition may contribute to soil degradation, and have harmful biological effects by degrading to toxic products. The toxicity of the examined pesticides is well known, however very little information is available regarding their natural degradation processes, the quality, structure and biological impact of the degradation products.
The photolytic degradation of frequently applied pesticides of distinctive types (acetochlor – acetanilide, simazine – triazine, chlorpyrifos – organophosphate, carbendazim – benzimidazole) was investigated. A special, immerseable UV-light source was applied in order to carry out photodegradation. The degradation processes were followed by thin layer chromatography (TLC) and mass spectrometry coupled with gas chromatography (GC/MS). EI mass spectrometry was used to identify the degradation species.
Each of the studied pesticides underwent photolytic decomposition, and the detailed mechanism of photolytic transformation was established. At least four degradation species were detected and identified in each case. Loss of alkyl, alkyloxy, amino-alkyl and chloro groups might be regarded as typical decomposition patterns. Deamination occurred at the last stage of decomposition.