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Applicability of hyperspectral technology for in situ phytoremediation
71-78Views:143The 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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Using integrated remote sensing methods in the Nagyerdő Natura 2000 area
19-24Views:213The more widely use of GIS, remote sensing technology provides appropriate data acquisition and data processing tools to build several national and international biodiversity monitoring system of environmental protection and natur conservation. The ChangeHabitats 2 is a similar international project, which uses airborne hyperspectral and airborne laser scanning (airborne LiDAR) sources beyond traditional data collection methods to build a monitoring system of Natura 2000 habitats. The goal of our research, on one hand, was to separate the most typical species of trees which can be found in the largest coverage in the research plots of Debreceni Nagyerdő Nature Reserve from field and airborne remote sensing data, use image classification that based on spectral and geometry (height) characteristics of the trees. On the other hand our goal was to evaluate the efficient use of the integration of mobilGIS, airborne hyperspectral and airborne LiDAR data collecting methods to complement or substitut of the traditional, field data collecting methods. We used ArcGIS 10.2 and Exelis 5.0 GIS software for data evaluation, in which the mosaicing, the selection of plots and the spectral image processing were carried out.
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Examination of soil parameters based on the evaluation of the spectroradiometric reflectance characteristics of the topsoil
75-80Views:186In this article we are presenting the methodology applied to analyse and interpret the topsoil surface reflectance parameters of multiple samples collected in the Mugello valley area in northern Italy in October 2012. The main aim of the whole project was to discover geomorphological behaviour and situation of the area ino order to improve potential for correct dating of certain archaeological artefacts found in the nearby areas. One of the crucial problem researchers are facing in the area is the lack of understanding of the underlying geological and geomorphological processes that were describing and characterizing the area and that played important role not only in the current geography and landscape formation but also in the transportation of various sediments and artefacts. In this particular research the main aim is to examine the possibility of developing a quick way to assess low level properties of the soil using hand held spectrometer and rapid analysis of cross-section using in situ measurement techniques. In this work we collected over 2000 individual samples of topsoil surface reflectance properties that we organized into a spectral library. This library is then to be used to describe physical and chemical processes in the soil. To support the analysis results were compared to analysis results from different kind of assessments in the same area. Our results show a great potential of application of hand held imaging spectrometer in soil property analysis based on the top soil surface reflectance parameters.
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Effects of combined nutrient supply treatments on some physiological parameters of autumn wheat
241-251Views:161The Fleischmann Rudolf Research Institute in Kompolt is not only famous for plant breeding but the institute also surveys the effects of different nutrient supply methods since 1918. In 2017, we joined this research supported by EFOP 3.6.1 project. Our aim was to investigate photochemical processes – which is one of the most determinant in case of yield – of crops by in vivo field measurements. We measured the chlorophyll content of leaves using Minolta SPAD 502. We used miniPAM fluorometer to determine actual photochemical efficiency and non-photochemical quenching of PSII during natural light conditions and also to evaluate the pigment (chlorophylls and carotenoids) and water content of leaves we applied field spectrophotometer (ASD FieldSpecPro 3). We utilized these methods by various treatments (1. treatment with soil bacteria + head and base fertilizer; 2. treated by only head fertilizer; 3. treated by only base-fertilizer) in field experiment of autumn wheat (4.1–2.43–1.19 ha) in June, 2017. The difference between treatments was clearly detectable. In the case of the first treatment, physiological processes were more intense and the ripening occurred earlier. The obtained yield was the highest in the case of the area treated by soil bacterial. Based on the results, the first treatment can be recommended in practice.
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Applicability of precision weed detection technologies
163-168Views:219In an agricultural field or horticultural plantation, weeds compete with cultivated plants for water and nutrients. The transpirated water by the weeds is needed to be replaced, which saddles surplus costs on the farmer, which could reduce the profitability of crop production. The aim of the precision plant protection system is to protect cultivated plants by applying site-specific technologies and optimized herbicides combination and methods, without environmental damage. The first step of precision weed control is the scouting for weeds. Traditional and modern (passive and active remote sensing) weed surveying technologies are available to detect weeds. The examination was carried out in an intensive apple orchard with drip irrigation system, protected by hail net of the Study and Regional Research Farm of the University of Debrecen near Pallag. The spectral-based weed detection was worked out by the Tetracam ADC broadband multispectral camera and the GreenSeeker 505 vegetation indexmeter. A strong correlation observed between vegetation indices and weed coverage. Based on the collected data, weed maps are created in appropriate software environment, thus the spatial distributions of the weeds are determined. The species level discrimination and the recognition of weed structural parameters were executed based on the 3D point cloud data by Leica ScanStation C10 laser scanner.
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Classification of a diffuse heavy metal polluted mining site using a spectral angle mapper
119-123Views:136Characterization 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.