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Forest monitoring using the GEDI sensor
Šedová, Adéla ; Potůčková, Markéta (advisor) ; Moudrý, Vítězslav (referee)
The overall objective of this thesis was to explore the use of GEDI and its integration with Airborne Laser Scanning (ALS) for large scale forest monitoring. The study was carried out using a sample of GEDI footprints that fell into the timeline of three available ALS datasets that were acquired during the same year. The study area, located in Southeast of Czechia, is covered with mature 121-year-old forest monoculture of Norway spruce (Picea abies), and due to frequent disturbances caused by infestation is closely monitored as a part of research on forest dynamic. As a result, the forest is highly fragmented, and due to its dynamic character, close dates of acquisitions were preferred to a larger dataset. Canopy gaps and low tree densities are known to pose a challenge for large-footprint full-waveform LiDARs. The specific of GEDI sensor, such as its footprint size, were specially designed to overcome these challenges. The options of optimising GEDI's geolocation accuracy were explored. A tool for integrating GEDI and ALS data, the GEDI Simulator, was used to standardise both data sources and derive elevation height, Relative Height (RH) and Canopy Cover Fraction (CCF). The metrics were derived from real GEDI waveforms, simulated GEDI-like waveforms, and calculated from the ALS point cloud, and...
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Predictive distribution modelling of selected bryophyte species in Bohemian Switzerland National Park
Procházková, Martina ; Man, Matěj (advisor) ; Moudrý, Vítězslav (referee)
The aim of this thesis was to create potential distribution models for Dicranum majus (Greater Fork Moss) and Polytrichum alpinum (Alpine Haircap) in Bohemian Switzerland National Park. In the Czech Republic these bryophyte species occur in cold climatic regions typically with higher altitudes. In Bohemian and Saxon Switzerland they can occur in really low altitudes thanks to unique microclimatic conditions of deep inversion ravines. These bryophyte species had low number of occurence records in studied area before the start of my research (4 occurence localities for Dicranum majus, 8 occurence localities for Polytrichum alpinum). Predictive habitat suitability models can be an effective tool for selecting potential new occurence localities, planning field research or management design. During field research I recorded 34 new occurence localities for Dicranum majus and 29 new occurence localities for Polytrichum alpinum in Bohemian Switzerland National Park. I used 8 topographic parameters derived from digital elevation model with 1 m resolution as environmental data. Using these data I created models of potential distribution of the most suitable habitats for both species with algorithms Artificial neural networks (ANN), Generalised linear model (GLM) and Random forest (RF). RF algorithm had the...
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Uncertainty associated with survey design in species distribution models
Vrabeľ, Matej ; Moudrý, Vítězslav (advisor) ; Barták, Vojtěch (referee)
Properly choosen input data, their form, way of the collection an the following correction as well, are the key factors affecting the accuracy of the more and more popular models of the species model distribution (SDM). A design unfluence of the data to the choosen distribution model of the virtual species has been tested. The General Linear Model (GLM) has been used. Four types of the present-absent collection designs have been tested for a virtual species on the area of the Czech Republic as follows: accidental, systematic, points on the easy accessible areas (near the communications) and the points with the higher concentration of the scientists (an area of CHKO).The TSS (True skills statistics), KAPPA and AUC (Area under curve) have been used to compare the accuracy of the prediction of the models .The points being choosen from the easy to access areas and CHKO had worse results in all of the monitored values than the accidental or the systematic choice of the points from the whole area of the Czech Republic.It results that the data collection mode affects the final accuracy of the species distribution models.
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Impact of horizontal and vertical pattern of habitats on birds diversity
Schovánková, Hana ; Šímová, Petra (advisor) ; Moudrý, Vítězslav (referee)
This diploma thesis follows up the influence of horizontal and vertical structure of biotopes on biodiversity of bird species of Czech Republic of forest and open sites. Vertical structure model was created from digital model of surface of Czech Republic (1st generation) and digital model of relief of Czech Republic (5th generation). Information about horizontal structure were derived by analyzing aerial imagery. Then single variables were detected from these data. Subsequently, it was analyzed which of these variables and which way influence bird diversity. On both types of sites was found increasing bird diversity with increasing diversity of vertical structure. With increasing horizontal structure, however, bird diversity significantly increased only on open sites. The influence of other characteristics was mostly different on bird diversity of open and forest sites, but, for both types of sites, the positive influence had for example edge density of land cover categories or edge density of height categories. Additional part of this thesis was to explore if vertical characteristics of biotopes could influence prediction of selected bird species. Results was different in forest and open biotopes, nevertheless in both types of sites was found potential use of both horizontal and vertical variables.
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Cadastral map visualization using ArcGIS and QGIS
Šilháček, Ondřej ; Barták, Vojtěch (advisor) ; Moudrý, Vítězslav (referee)
The aim of this work is to create a project in ArcGIS and QGIS that is based
on a visualization of a cadastral map in a format for storing vector spatial data:
shapefile. Spatial features contained in the map have correctly set vector
coordinates, but their style, attributes and properties are in default settings. The task
was to configure all the settings to match the style of the cadastral map. The final
project was meant to be used as a tool that can be applied to other cadastral maps
in default settings in order to change their style into the style of the cadastral maps.
Created style was saved as files that contain information about the properties
that were configured in shapefiles, but they do not contain spatial data, only the
information about their location. Shapefiles were styled according to the cadastral
regulation no. 357/2013 Coll. Created project expands possibilities of how cadastral
maps can be browsed and it will be used for potential customers of the Czech Office
for Surveying, Mapping and Cadastre in Prague who will apply for the cadastral map
in shapefiles.
Theoretical part contains characterization of ArcGIS, QGIS, possibillities of
how cadastral maps can be currently obtained and browsed. Also a brief history of
cadastral maps in the territory of the Czech state. As there are no guidelines, which
could be used for the cadastral map visualization, the methodology does not contain
informations about the process of creating the project, but only instructions that
determine how the final project should look like. Results contain detailed
informations about the process of creating the project with all partial steps including
visualization of shapefiles, saving the project and information how to run the project.
At the end of the theoretical part is an evaluation of the user friendliness, pros and
cons and the overall view of the work with used programs in the meaning of
shapefile visualization.
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Modelling potential distribution of invasive plants Indigo bush (Amorpha fruticosa) and Goji berry (Lycium barbarum) in the Czech Republic
Müllerová, Soňa ; Moudrý, Vítězslav (advisor) ; Barták, Vojtěch (referee)
Biological invasions are currently considered to be one of the major threats to biodiversity. Invasive species are introduced species naturalized in regions outside their native range with both ecological and economic impact known from many regions all over the world. In the Czech Republic, vascular plants constitute a major group of invasive species. They are characterized by the ability to adapt, spread and occupy new sites. Early identification of potentially dangerous species constitute a possible way to prevent further spread. This bachelor thesis presents the use of species distribution modelling technique as a tool for assessing invasive potential and predicting species invasions. The aim was to create the model of invasive shrub species Indigo bush (Amorpha fruticosa) and Goji berry (Lycium barbarum) potential distribution in the Czech Republic and explore the significance of each predictor variable including variables derived from digital elevation model. Models were created in the resolution of 100 m using Maxent method based on presence-only data and ten predictor variables including three topographic variables: elevation, slope and aspect. The results show that the most significant variables for both species are elevation, land cover which is the most important one for Amorpha fruticosa, and temperature annual range. Slope variable is significant for Lycium barbarum. Aspect is not significant. In terms of AUC discrimination measure, high values were achived for both species. AUC value for Amorpha fruticosa is 0,961 and 0,906 for Lycium barbarum. However, the realism and quality of the model is significantly influenced by the stage of invasion and also by complexity and accuracy of input data.
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OpenStreetMap contributor activity in the Czech Republic
Vaidiš, Martin ; Moudrý, Vítězslav (advisor) ; Komárek, Jan (referee)
Today on the internet, the amount of User generated content (UGC) is increasing as fast as never before. One of its very well usable representatives are Volunteered geographic informations (VGI), which were recently gathering a lot of interest. This applies especially on the most succesfull project based on collaborative mapping - OpenStreetMaps (OSM). Beside the brief introduction of VGI and its possibilities of use, the literature research part of this work takes a closer look at OSM, its structure and its comunity of more than two and a half millions members. The paper also presents ways to get information about the activity of contributors, which is then applied it the analytical part of the work. That is mainly focused on active users in the Czech Republic and its neighbours - Germany, Poland, Slovakia and Austria. By examining data of one year, it was found, among other facts, that the number of contributors in Czech Republic is increasing much more slowly than in the community as a whole. Also, the ratio of the most active members in Czech Republic is significantly lower than usual. The results also showed, that the number of edits made to the OSM database by an average Czech contributor is significantly greater than by others, which were inclueded in this reaserch. At the same time, the importance and potential causes of these anomalies are discussed, and finally, it is proposed how the results may be used for future research.
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Changes in volume of water reservoir Fojtka due to sediment flux
Vlasák, Tomáš ; Moudrý, Vítězslav (advisor) ; Hradilek, Václav (referee)
Sedimentation in dams is a natural process depending on various factors over a period of time. Sediments influence both total capacity of dam's surface and also relief of bottom.
This thesis deals with amount of sediment in Fojtka dam and with change of its bottom's relief in past 109 years since its establishment. There was conducted measuring using an echosounder in a boat. Final output derived from this experiment was a point layer including 5500 point items. Subsequently there was executed a measurement of dam's shoreline using GPS device. Data were processed in ArcGIS software, then reduced and edited to be used for interpolation tools of ArcToolbox. In order to select the most accurate interpolation method, there were created validation data, which were compared with interpolated data. The best results have been achieved by interpolation method Kriging and TIN in resolution 0.5 m.
Original maps were vectorized for comparison with current condition. Created validation data were compared in order to show accuracy of particular interpolation. The most useful evaluated method for gained data was TIN method in resolution 0.5 m. TIN method was applied in both data sets for 2D and 3D bottom relief visualization and also for calculation of actual water volume and area of water surface of the dam.
Difference in bottom's relief of Fojtka dam showed capacity reduction about 6,7 % and reduction of water surface area about 3,2 %. Regular extracting of sediment in reservoir located above the dam causes this relatively small silting ratio.
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Quality assessment of the OpenStreetMap data in Prague
Zídek, Jan ; Moudrý, Vítězslav (advisor) ; Šímová, Petra (referee)
OpenStreetMap (OSM) is the largest and objectively the most successful project from all attempts to open-source alternative to commercial map databases and projects of the official agencies. OSM is widely popular in Czech Republic, but the quality of this VGI (volunteered geographic information) dataset has not yet been studied. This master thesis evaluates several aspects of quantifiable characteristics of buildings in Prague. The objective was to primarily evaluate completeness, semantic accuracy and shape accuracy of building footprints. Data from OSM were compared with Digital map of Prague by Geoportal Prague, which is the official map resource covering the area of the city Prague. The data processing was done in ArcGIS by the ESRI company. The results show that OSM in Prague have high semantic accuracy and almost 100% completeness in terms of total area, but more than 50% of buildings are missing basic descriptive data. In terms of shape accuracy the footprints were identified by smaller amount of vertices than the footprints from Geoportal Prague and in some cases certain architectural details were missing.
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Do environmental filters improve predictions of species distribution models ?
Gábor, Lukáš ; Moudrý, Vítězslav (advisor) ; Barták, Vojtěch (referee)
Species distribution models (SDM) are widely used tool in biogeography, macroecology and nature conservation. With gradual development, it has become an important means used by, for example, in determining the potentially threatened locations by invasive species, or studying the impact of climate change on biodiversity. With the progressive development it becomes obvious that one of the major factors limiting the species distribution modelling are input data. The presence data are most readily available, but they suffer from an uneven collection, for example, with a predominance of records in easily accessible locations. The aim of this work is to show, that popular climate filtering of presence data input, in order to eliminate uneven sampling, affects the final model in a negative way. For this purpose, there were virtual sorts of different species and different prevalence of recorded occurrences on the territory of the Iberian Peninsula generated. Subsequently, species distribution models with and without climate filters were created by using Maxent. They were evaluated by AUC. The difference between virtual reality, which is presented to the suitability of the virtual species, and the resulting model was tested by paired T test. Comparison of the AUC confirmed that the species distribution models based on climate filtering have better discriminative ability. However, it only points to the skilful work with the selected sample bias that already does not reflect reality. In contrast, comparison of the differences between virtual reality and the models with and without climate filtering using a paired T test shows greater congruence between unfiltered models and virtual reality. Thus it was proved that the climate filtering does not lead to higher validity species distribution models.
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