National Repository of Grey Literature 25 records found  previous11 - 20next  jump to record: Search took 0.02 seconds. 
Land cover change detection on the agriculture land
Klouček, Tomáš ; Štych, Přemysl (advisor) ; Brodský, Lukáš (referee)
The main purpose of thesis is creation and evaluation of models for change detection of arable land to grassland by Hybrid-based Change Detection method, which combined approaches based on the Vegetation Indices, Image Differencing and Principal Component Analysis. Six locations with different seasonal configuration of images with high resolution and one locality covered by image with very high resolution were used. The areas were spread across the foothill areas of the Czech Republic. The selection of predictors and the most suitable model was supported by statistical calculation. Application selected models were carried out using a multi-temporal object classification and their accuracy were verified using reference data. The benefit of this thesis is finding generally applicable model useful to investigate the land cover change and evaluation of the potentially most appropriate seasonal configuration of images. Valuable is also methodology in this thesis which focus on selection of predictors and calculation the order of the most appropriate models, which is unique in the available literature. The thesis provides useful findings fitting to insufficiently explored issue of Change Detection arable land to grassland. Powered by TCPDF (www.tcpdf.org)
The use of vegetation indices to study temporal variation in vegetation phenology
Beránková, Petra ; Štych, Přemysl (advisor) ; Hesslerová, Petra (referee)
1 ABSTRACT The work deals with the use of vegetation indices to study temporal variation in vegetation phenology. The first part was devoted to detailed analysis of domestic and foreign literature, which deals with the work processed in this field. The main research questions were if changed start, end and length of growing period during the analysis period. Other research theme was comparision with ground phenological data. Another objective of this work was search dependencies computed data phenological variables from vegetation indicies with phenological ground data. As a basic data set was used GIMMS set, which distributes the vegetation index NDVI. Other data sets were MERIS MTCI, data MODIS with vegetation indices NDVI, EVI a LAI. The results of analyzes of vegetation phenology show trends in most shifts at the beginning of growing season, where was a shift to an earlier time. Results of the analysis of vegetation remote sensing data with ground-based phenological data ČHMÚ were unfolding always according to the specific forest phenological stations. Interesting results were at the phenological station Svoboda nad Úpou, where the results of trends directives were consistent in almost all data sets. Comparison of process curves vegetation indicies with ground data corresponded most curves at selected...
Use of laboratory and image spectroscopy to evaluate drought resistance of Scots pine and to distinguish its ecotypes
Raasch, Filip ; Kupková, Lucie (advisor) ; Potůčková, Markéta (referee)
The aim of this study was to propose a non-destructive method for measuring Pinus sylvestris seedlings, to determine whether water stress would be evident in laboratory spectra of pines, to compare whether the response of pines would differ by ecotype, and to investigate whether two ecotypes of Pinus sylvestris could be distinguished using laboratory and image spectroscopy. For these purposes, hyperspectral images of seed orchards from August 2020 were processed and a three-month laboratory experiment was conducted, in which stress from water deficit was induced in two-year-old pine seedlings from the upland and hilly ecotypes. Spectral data were analysed using mixed statistical models, analysis of variance, principal component analysis, training of supervised pixel classifiers, vegetation indices, and linear regression. Based on the analyses, it was found that water stress can be detected in severely stressed Pinus sylvestris seedlings. The most sensitive spectral bands to water content were observed in the region between 1000-2500 nm. The initial response to water stress did not differ by ecotype, but a faster recovery was observed at the upland ecotype after the period of draught. The two Pinus sylvestris ecotypes were distinguished with high accuracy from both laboratory and image spectral...
Využití dálkového průzkumu pro odhad výnosů zemědělských plodin
Rosendorfská, Eva
Knowledge og the crop yield with sufficient lead time prior to harvest is crucial for the farm management or national agro-food policy. Spectral characteristics provided by satellite based remote sensing have both spatial and temporal resolution which allow crop yields from agricultural fields. The aim of this thesis was to test feasibility of developing crop yield. The study was focused on three major crops in the Czech Republic: spring barely, winter wheat and oilseed rape. The crop yield data were collected from 14 districts that represent regions with more intensive agricultural production and include a variety of climate, topographic and soil conditions. As a main data source for this thesis was series of digital images acquired by MODIS (Moderate Resolution Imaging Spectroradiometr) aboard Terra satellite from 2001-2014 period. Were analyzed two vegetation idices NDVI (Noramized Difference Vegetation Index) and EVI (Enhanced Vegetation Index) from the 16-days composite product with a spatial resolution of 250 m. In most cases, EVI showed higher correlations to the crop yied, which can be explained due to the negative saturation effect of NDVI.
Identification of potentially suitable habitats for occurrence of European Ground Squirrel (Spermophilus citellus) using remote sensing
Kadeřábková, Tereza ; Kupková, Lucie (advisor) ; Hais, Martin (referee)
The aim of the thesis was to evaluate the possibilities of remote sensing (RS) data with different spatial resolution (UAV data with 5cm resolution, RapidEye satellite data with 5m resolution and Sentinel-2A data with 10m resolution) and of remote sensing methods (unsupervised and supervised classifications, vegetation indices NDVI and TVI) to identify potentially suitable habitats for European ground squirrel. The analyses were first carried out in Velké Pavlovice small area of interest and consequently in a broader area of interest comprised of five regions of Moravia and Slovakia. Data form mapping of biotopes and squirrels' burrows collected within a project "Sysli pro krajinu, krajina pro sysly" (European ground squirrels for landscape, landscape for European ground squirrels) were also used for the analyses. Remote sensing methods were first tested in Velké Pavlovice area using RapidEye data. The method providing the best results in the detection of European ground squirrel burrows was then used for a burrows detection in the broader area of interest (five regions) using Sentinel-2A data. The accuracy of results was defined as a proportion of the burrows detected by the resulting layer derived from RS data to the overall number of burrows mapped in the field. Best results were obtained for...
Land cover change detection on the agriculture land
Klouček, Tomáš ; Štych, Přemysl (advisor) ; Brodský, Lukáš (referee)
The main purpose of thesis is creation and evaluation of models for change detection of arable land to grassland by Hybrid-based Change Detection method, which combined approaches based on the Vegetation Indices, Image Differencing and Principal Component Analysis. Six locations with different seasonal configuration of images with high resolution and one locality covered by image with very high resolution were used. The areas were spread across the foothill areas of the Czech Republic. The selection of predictors and the most suitable model was supported by statistical calculation. Application selected models were carried out using a multi-temporal object classification and their accuracy were verified using reference data. The benefit of this thesis is finding generally applicable model useful to investigate the land cover change and evaluation of the potentially most appropriate seasonal configuration of images. Valuable is also methodology in this thesis which focus on selection of predictors and calculation the order of the most appropriate models, which is unique in the available literature. The thesis provides useful findings fitting to insufficiently explored issue of Change Detection arable land to grassland. Powered by TCPDF (www.tcpdf.org)
Markers of pine physiological state in relation to genetic variability
Šafránková, Anna ; Albrechtová, Jana (advisor) ; Prášil, Ilja (referee)
Breeding of coniferous trees in the Czech Republic is undergoing an important development during last decades, especially thanks to molecular-genetic methods, which refine and simplify mapping of tree genotypes and the selection of superior genotypes. Recently, in the Czech Republic superior genotypes are selected based on forestry parameters (tree height, trunk diameter, and timber quality) what does not always correlate with the ability of a tree to resist abiotic and biotic stresses. Recently, there is an effort to include in the breeding also physiological parameters and select superior genotypes using nonspecific stress indicators, which are able to correspond better to tree fitness than the forestry growth parameters. The present thesis deals with genotypes of Scots pine (Pinus sylvestris L.) growing in seed orchards Doubrava and Silov in the Pilsen region in the Czech Republic. Seed orchards are tree plantations, which serve as a reserve of the genetically valuable reproduction material, they are parts of breeding programs. Pine needles were collected in July 2015 and analyzed for non-specific stress indicators - photosynthetic pigments, phenolics, lignin, cellulose and proline contents and leaf reflectance and fast chlorophyll fluorescence measurements. First objective of the present thesis...
Evalution of Time Series of Satellite Images to Observe Disturbancec in the Low Tatras
Laštovička, Josef ; Štych, Přemysl (advisor) ; Hais, Martin (referee)
The work is aimed at finding appropriate methods for observing changes in the status of forest vegetation and its evaluation in the years 1992-2015. The satellite images of the Low Tatras are analyzed by using Time Series technology. Specifically, the images Landsat 4, 5, 7 and 8, for which it is necessary to perform a calibration and an adjustment of input data values to realize the individual vegetation indices, due to the fact that the images are captured by different sensors with different radiometric resolution. From this perspective, the work deals with the possibilities of normalized relative radiometric corrections and search for a particular type of appropriate compensation for Landsat CDR images. Calibrated data sets are evaluated by Time Series of different vegetation indices. The resulting values are evaluated in relation with the occurrence of forest disturbances, eg. wind storms, biological and other pests. The final part is discussion of the results, evaluating the test methods of calibration and suitability of vegetation indices for observing the state of calamity. The App is created for generating the Time Series of Landsat images CDR and for preparing RRN datasets. Key words: Time Series, radiometric correction, atmospheric correction, Landsat CDR, vegetation indices,...
Development of selected invasive species and meadow vegetation classification algorithm in the Krkonoše Mountains using hyperspectral data
Jelének, Jan ; Kupková, Lucie (advisor) ; Halabuk, Andrej (referee)
Development of selected invasive species and meadow vegetation classification algorithm in the Krkonoše Mountains using hyperspectral data Abstract The thesis deals with utilization of airbone APEX hyperspectral image data for selected invasive species and meadow vegetation classification in the study area of the Krkonoše Mountains National Park. The mian goal of the thesis was to develop of classification algorithm based on proposed vegetation indices. The approach was based on the utilization of in-situ LAI, fAPAR, chlorophyll content data and analysis of their relation with vegetation spectral properties. The work also deals with several problems regarding LAI - vegetation indices relationship, namely saturation of LAI and mutual correlation of LAI and chlorophyll content. Tha classification was focued on invasive species Rumex alpinus and Lupinus polyphyllus, meadow vegetation with dominant Nardus stricta and dominant Trisetum flavescens and cutted lawns. Besides the proposed approach, the presented work resulted in several classification maps of study area and in spectral libraries, containing ground level spectra of studied invasive species, meadow vegetation types and several other meadow species. Keywords: hyperspectral image data, APEX, LAI, fAPAR, vegetation indices, invasive species, meadow...
The use of vegetation indices to study temporal variation in vegetation phenology
Beránková, Petra ; Štych, Přemysl (advisor) ; Hesslerová, Petra (referee)
1 ABSTRACT The work deals with the use of vegetation indices to study temporal variation in vegetation phenology. The first part was devoted to detailed analysis of domestic and foreign literature, which deals with the work processed in this field. The main research questions were if changed start, end and length of growing period during the analysis period. Other research theme was comparision with ground phenological data. Another objective of this work was search dependencies computed data phenological variables from vegetation indicies with phenological ground data. As a basic data set was used GIMMS set, which distributes the vegetation index NDVI. Other data sets were MERIS MTCI, data MODIS with vegetation indices NDVI, EVI a LAI. The results of analyzes of vegetation phenology show trends in most shifts at the beginning of growing season, where was a shift to an earlier time. Results of the analysis of vegetation remote sensing data with ground-based phenological data ČHMÚ were unfolding always according to the specific forest phenological stations. Interesting results were at the phenological station Svoboda nad Úpou, where the results of trends directives were consistent in almost all data sets. Comparison of process curves vegetation indicies with ground data corresponded most curves at selected...

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