Height of successional vegetation indicates moment of agricultural land abandonment

One of the major land use and land cover changes in Europe is agricultural land abandonment (ALA) that particularly affects marginal mountain areas. Accurate mapping of ALA patterns and timing is important for understanding its determinants and the environmental and socio-economic consequences. In highly fragmented agricultural landscapes with small-scale farming, subtle land use changes following ALA can be detected with high resolution remotely sensed data, and successional vegetation height is a possible indicator of ALA timing. The main aim of this study was to determine the relationship between successional vegetation height and the timing of agricultural land abandonment in the Budzów community in the Polish Carpathians. Areas of vegetation succession were vectorized on 1977, 1997, and 2009 orthophotomaps, enabling the distinguishing of vegetation encroaching on abandoned fields before and after 1997. Vegetation height in 2012-2014 was determined from digital surface and terrain models that were derived from airborne laser scanning data. The median heights of successional vegetation that started development before and after 1997 were different (6.9 m and 3.2 m, respectively). No significant correlations between successional vegetation height and elevation, slope, aspect, and proximity to forest were found. Thus, the timing of agricultural land abandonment is the most important factor influencing vegetation height, whereas environmental characteristics on this scale of investigation may be neglected

Vector algebra for Steep Slope Model analysis

Geographic Information Systems offer many algorithms that allow analysis of digital elevation models. They work with both GRID and TIN data, but they are limited to 2.5D models, where one planar (X,Y) position refers to only one vertical (Z) value. In mountainous regions, however, many steep, vertical and even overhung parts of rock walls and slopes occur. GRID and TIN models in a standard projection are not capable to deal with such a relief as they are not able to capture all complexity of steep slopes that can be observed from the terrestrial perspective. Such a perspective can be introduced into GIS via computer graphics software that allows 3D surface modelling by means of \mathit{mesh}, e.g. 3D triangular network. The paper presents a concept that implements 3D mesh in GIS and utilizes vector algebra to analyze such a surface. The idea is based on using normal vectors to compute slope and aspect of each triangle in a mesh. The computed values are saved as their attributes. Complete procedures are written in Python programming language and implemented into popular GIS software to work as a plug-in tool

Photo-based 3D scanning vs. laser scanning : competitive data acquisition methods for digital terrain modelling of steep mountain slopes

The paper presents how terrestrial laser scanning (TLS) and terrestrial digital photogrammetry were used to create a 3D model of a steep mountain wall. Terrestrial methods of data acquisition are the most suitable for such relief, as the most effective registration is perpendicular to the surface. First, various aspects of photo-based scanning and laser scanning were discussed. The general overview of both technologies was followed by the description of a case study of the western wall of the Kościelec Mountain (2155 m). The case study area is one of the most interesting and popular rock climbing areas in the Polish High Tatra Mts. The wall is about 300 meters high, has varied relief and some parts are overhung. Triangular irregular mesh was chosen to represent the true3D surface with its complicated relief. To achieve a more smooth result for visualization NURBS curves and surfaces were utilized. Both 3D models were then compared to the standard DTM of the Tatra Mountains in TIN format, obtained from aerial photographs (0.2 m ground pixel size). The results showed that both TLS and terrestrial photogrammetry had similar accuracy and level of detail and could effectively supplement very high resolution DTMs of the mountain areas

Relief and values of landscape metrics : a case study from the Tatra Mts

W niniejszej pracy zaprezentowano wyniki porównania wartości wybranych metryk krajobrazowych otrzymanych na podstawie obliczeń wykonanych dwiema metodami: metodą tradycyjną, w której pomiarów dokonuje się po zrzutowaniu mozaiki jednostek przestrzennych na powierzchnię planimetryczną, oraz metodą uwzględniającą trzeci wymiar krajobrazu - opartą na analizie numerycznego modelu terenu. Badania wykazały, że zastosowane metody mogą mieć wpływ na uzyskany obraz struktury krajobrazu wysokogórskiego. Ponadto w pracy zawarto uwagi dotyczące obliczania średniej szorstkości powierzchni oraz analiz wykonywanych przy wykorzystaniu pól geometrycznych w danym typie krajobrazu.The aim of the authors was to compare values of 2D and 3D landscape metrics in high mountains. The first part of the work takes into consideration the spatial structure of vegetation (the rank of landscape facias/ecotopes) of Kocioł Goryczkowy Świński, which was investigated in 1999 by Anna Kozłowska and Anna Jakomulska. The calculation of landscape metrics is resumed using the true surface geometries and compared with the result of traditional measurements on a reference plane. In the second part of the paper, a set of commonly used landscape metrics is calculated for the geocomplexes (rank of uroczysko unit) in the Morskie Oko catchment using both true surface and plain geometries. Finally average surface roughness is computed for the both study areas and some remarks for landscape metrics computed for geometric fields are given. The comparison shows that appropriate 2D and 3D metrics may differ significantly. Moreover, there is a strong correlation between the size of the discrepancy and the surface slope. For that reason, it is very important to distinguish between 2D and 3D metrics and to use them consciously, according to the particular problem

Integration of GIS and virtual reality for geographic data visualization and exploration

Kartografia 3D i wizualizacja 3D danych geograficznych cieszą się obecnie dużą popularnością. Uważa się, że sposób wizualizacji jest tak ważny jak sama treść mapy, a trójwymiarowy GIS jest bardziej komunikatywny od dwuwymiarowego. Ten artykuł prezentuje, jak w prosty sposób połączyć kartografię, GIS i wirtualną rzeczywistość w celu wizualizacji, analizy i eksploracji danych. Do wykonania map i trójwymiarowej wizualizacji danych użyto oprogramowania ESRI: ArcGIS i ArcScene, a wizualizacje bardziej realistyczne wykonano w programie Google SketchUp Pro 6, który umożliwia korzystanie z gotowych i tworzenie własnych modeli 3D oraz umieszczanie gotowych produktów w Internecie za pośrednictwem Google Earth. Jako dane wejściowe wykorzystano obrazy satelitarne, ortofotomapy, dane wektorowe, numeryczny model terenu oraz bibliotekę gotowych modeli 3D. Efektem były przestrzenne mapy zawierające dane ogólne i szczegółowe, wirtualne przeloty i profile wysokościowe, widoki panoramiczne oraz trójwymiarowe realistyczne modele. Oprócz zapewnienia kontekstu położenia geograficznego i orientacji, GIS 3D umożliwia plastyczne przedstawienie rzeźby terenu i elementów krajobrazu, a dane ilościowe mogą być prezentowane w postaci diagramów czy schematów. Rzeczywistość wizualizowana w jak najmniej abstrakcyjny sposób jest łatwiej rozumiana i pozwala skupić się na treści. Interaktywne wizualizacje idące w stronę wirtualnej rzeczywistości umożliwiają intuicyjną ocenę charakteru czy piękna krajobrazu i są bardzo pomocne w planowaniu.3D cartography and geographic data visualization are currently very popular. Compared to traditional methods, they allow a clearer presentation of a wider range of geographic content and facilitate interpretation. It is claimed that the manner of visualization is as important as the map content, and that 3D GIS has a higher communication power that two-dimensional GIS. It is of high importance for individuals who have not gained much experience in working with maps (especially for those having problems with correct relief perception) as well as for spatial planning (particularly the participatory aspect of it). This paper explores how traditional cartography, GIS, and virtual reality can be combined to visualize, analyze, and explore data. The first stage of the work involved map design and 3D visualization of spatial and attribute data. ArcGIS and ArcScene ESRI were used. Subsequently, to develop more realistic visualizations and facilitate communication with a user, Google SketchUp Pro 6 was used. The programme makes it possible to use the ready-made 3D models and to create one's own. It also allows to publish products in the Internet by Google Earth. Satellite images, orthophotomaps, feature data, digital terrain model, and Web library of the ready-made 3D models were used as source data. In effect, general and detailed maps, virtual flights, elevation profiles, panoramic views and three-dimensional realistic models were generated. Apart from providing a user with spatial context and orientation, the 3D GIS allows also to present the ground surface and landscape (natural and anthropogenic, e.g., a city) elements in an enhanced manner, while quantitative data may be showed as diagrams or other schematic images. The reality visualized at the lowest possible degree of abstraction is much easier to comprehend and allows to concentrate on the content. Satisfactory effects are obtained with digital terrain model and satellite images or orthophotomaps. Very complex visualizations, where the content is enriched in 3D models of trees, buildings, etc., and where it is possible to move, approach virtual reality. They allow the user to intuitively perceive the nature and beauty of a landscape, and are very helpful in planning

Ukształtowanie powierzchni terenu a wartości metryk krajobrazowych w górach wysokich na przykładzie Tatr

W niniejszej pracy zaprezentowano wyniki porównania wartości wybranych metryk krajobrazowych otrzymanych na podstawie obliczeń wykonanych dwiema metodami: metodą tradycyjną, w której pomiarów dokonuje się po zrzutowaniu mozaiki jednostek przestrzennych na powierzchnię planimetryczną, oraz metodą uwzględniającą trzeci wymiar krajobrazu – opartą na analizie numerycznego modelu terenu. Badania wykazały, że zastosowane metody mogą mieć wpływ na uzyskany obraz struktury krajobrazu wysokogórskiego. Ponadto w pracy zawarto uwagi dotyczące obliczania średniej szorstkości powierzchni oraz analiz wykonywanych przy wykorzystaniu pól geometrycznych w danym typie krajobraz

How does students motivation to acquire new geospatial skills influence their choices of e-learning content?

Higher education in many disciplines is affected nowadays by an evident orientation to assist students in developing a certain set of skills required by the labour market. This trend is visible also in the field of Geographic Information Science and Technology (GIS&T). The composition of competencies encompasses, apart from industry-specific technical competencies, also soft skills related to personal effectiveness, academic and workplace competencies. Moreover, soft skills are gaining in importance, being identified as future work skills. As a result, students may search for certain skills when they come into contact with a particular learning content. In this study, we investigated how the motivation to acquire specific skills influences students’ behaviour on the e-learning platform. As a case study, we selected a study programme in land management carried out at the Institute of Geography and Spatial Management (Jagiellonian University in Cracow, Poland). Several different motivating factors, like GIS&T skills and the ability to co-operate, were identified and compared with students’ behaviour on the e-learning platform in certain modules of the study programme. The results indicated that students only partially prospected for certain competencies during their work with the content of the e-learning platform. Students’ motivation was more evident in their on-line behaviour when they wanted to acquire technical skills than when they planned to develop soft skills