SPATIAL 3D DOCUMENTATION OF HISTORICAL MINING REMNANTS IN FORESTED AREA IN THE ERZGEBIRGE/KRUŠNOHOŘÍ MINING REGION UNESCO SITE

This contribution deals in the possibilities of 3D documentation of historical mining relicts hidden in the forest. On the Czech – German border, in the Ore Mountains, several historical mining relicts are located there. There are interesting underground spaces (historical mines), some of which have recently been made available for visits by tourists. But there are many relicts on the surface that are linked to mining and are not known or on the fringes of interest. These are mining pits, dumps, water works, remains of buildings and historic entrance roads. Many of them are in forest areas, were not documented or archaeologically explored, and have recently been devastated by amateur collectors equipped with metal detectors who unfortunately destroy unexplored localities to find interesting relicts. For the basic documentation and delimitation of these objects, aerial laser scanning (ALS) and personal laser mobile scanning (PLS) were used; some finds were documented by close-range photogrammetry.

Analysis of the Geomechanical Phenomena that Led to the Appearance of Sinkholes at the Lupeni Mine, Romania, in the Conditions of Thick Coal Seams Mining with Longwall Top Coal Caving

Thick coal seam no. 3, block V, Lupeni mine was mined by longwall top coal caving (LTCC). After the coal mining, the ground surface underwent continuous subsidence, but since 2008, three sinkholes have appeared on the surface with important dimensions, atypical for the geo-mining conditions in this coal basin. This article is a synthesis of the study meant to decipher the geo-mechanical phenomenon that led to the emergence of these sinkholes and highlighting the main factors that contributed to the development of this phenomenon. For this purpose, measurements were made on the terrain deformations using photogrammetric methods and aerial laser scanning, when modeling with 3D finite elements, in elasto-plasticity and with the help of the Knothe–Budrik influence function. The factors that contributed to the occurrence of discontinuous subsidence phenomena are shallow mining depth, the LTCC mining method, and the presence of faults in the vicinity of the mining panels. Additionally, the geo-mechanical phenomena of subsidence terrace development and sinkholes in the mining subsidence troughs at the Lupeni mine were described.

EFFICIENCY OF AERIAL LASER SCANNING OF THE TERRITORY WHEN MONITORING URBAN GREEN SPACES

The article describes the role of remote sensing technologies in monitoring urban green spaces. The positive aspects of the use of air laser scanning in the inventory and monitoring of urban green spaces are listed. The role of urban green spaces in the formation of an environmentally friendly urban environment is briefly described. Insufficient elaboration of the regulatory and legal documentation in the field of registration of urban green spaces in the Unified State Register of Real Estate Objects was noted. It is emphasized that the lack of approaches to the consideration of urban green spaces as independent cadastral objects entails numerous violations in the field of environmental and environmental legislation of settlements. A solution to this problem is proposed, which consists in the mandatory accounting of cadastral data on the land plot under the urban green spaces when maintaining the urban green spaces monitoring database.

Quantifying key metrics of ecosystem biodiversity in natural and managed sub-boreal forests of British Columbia

Forest management in the central interior of British Columbia has been active for over a century. Industrial forest practices in the region are based on the premise that harvest and subsequent stands regeneration is sustainable, but recent investigations raise questions about long-term ecological sustainability and impacts on biodiversity. I evaluate here, using a chronosequence of forest stands, the impacts of stand harvest on biodiversity status and recovery. Aerial laser scanning is used to enhance analysis and model impacts spatially. I provide a novel assessment of key biodiversity metrics of diversity, richness, abundance, and modeling using linear discriminant analysis and random forest frameworks. Results show that vegetation community composition and coarse woody debris (CWD), a key habitat for numerous taxa, are both impacted by harvest history. Predictive mapping of CWD provides insights and a further tool for decision makers to manage and ensure natural levels of CWD are maintained on the landscape.

Use of 3D models for control of the main pipeline protective facilities

The primary purpose of main pipelines is to transport oil products from a point to the point of destination. Therefore, its length can be thousands of kilometers, most often it is located in difficult natural and climatic conditions. Main pipeline continuous operation and protection from accidents or breakdowns requires passive or active control of protective structures using 3D technologies. The article briefly describes the technology for creating 3D models based on materials from aerial laser scanning and aerosurvey.

Chaos in Motion: Measuring Visual Pollution with Tangential View Landscape Metrics

Visual pollution (VP) in the form of outdoor advertisements (OA) is a threat to landscape physiognomy. Despite their proven usefulness in landscape aesthetic studies, landscape metrics have not yet been applied to address the phenomenon of VP. To fill this knowledge gap, a methodological framework for the measurement of VP using tangential view landscape metrics is proposed, which is accompanied by statistically significant proofs. Raster products derived from aerial laser scanning data were used to characterize two study areas with different topographic conditions in the city of Lublin, East Poland. The visibility of the cityscape in motion was simulated through viewshed measurements taken at equal intervals in the forwards and backwards directions along pedestrian walkways. The scrutinized tangential view landscape metrics (visible area, maximum visible distance, skyline, Shannon depth, view depth line) was the object of a two-fold interpretation wherein the spatial occurrence of VP as well as its impacts on the visual landscape character (VLC) were examined. The visible area metrics were found to be highly sensitive VP indicators. The maximum visible distance metrics provided evidence for the destructive effect of OA on view corridors. The Shannon depth and depth line metrics were not found to be statistically significant indicators of VP. Results from directional viewshed modelling indicate that distortion in the analyzed cityscape physiognomy depends on the view direction. The findings allow for particular recommendations with practical implementations in land use planning, which are discussed along with limitations to our proposed methods.

Investigating the Impact of Digital Elevation Models on Sentinel-1 Backscatter and Coherence Observations

Spaceborne remote sensing can track ecosystems changes thanks to continuous and systematic coverage at short revisit intervals. Active remote sensing from synthetic aperture radar (SAR) sensors allows day and night imaging as they are not affected by cloud cover and solar illumination and can capture unique information about its targets. However, SAR observations are affected by the coupled effect of viewing geometry and terrain topography. The study aims to assess the impact of global digital elevation models (DEMs) on the normalization of Sentinel-1 backscattered intensity and interferometric coherence. For each DEM, we analyzed the difference between orbit tracks, the difference with results obtained with a high-resolution local DEM, and the impact on land cover classification. Tests were carried out at two sites located in mountainous regions in Romania and Spain using the SRTM (Shuttle Radar Topography Mission, 30 m), AW3D (ALOS (Advanced Land Observation Satellite) World 3D, 30 m), TanDEM-X (12.5, 30, 90 m), and Spain national ALS (aerial laser scanning) based DEM (5 m resolution). The TanDEM-X DEM was the global DEM most suitable for topographic normalization, since it provided the smallest differences between orbital tracks, up to 3.5 dB smaller than with other DEMs for peak landform, and 1.4–1.9 dB for pit and valley landforms.

THE FUSION OF EXTERNAL AND INTERNAL 3D PHOTOGRAMMETRIC MODELS AS A TOOL TO INVESTIGATE THE ANCIENT HUMAN/CAVE INTERACTION: THE LA SASSA CASE STUDY

Caves have been used by humans and animals for several thousand years until present but, at these time scales, their structures can rapidly change due to erosion and concretion processes. For this reason, the availability of precise 3D models improves the data quality and quantity allowing the reconstruction of their ancient appearance, structure and origin. However, caves are usually characterised by lack of light, high percentage of relative humidity, narrow spaces and complex morphology. Thus, quite often the traditional topographic instruments cannot be employed. In the La Sassa cave (Sonnino, Italy) a huge deposit ranging from Pleistocene to the Second World War has been found and stratigraphic evidence suggested that the shape of the cave and its entrance might have been different. In this paper, the fusion of the internal and external 3D photogrammetric models of the La Sassa, made to support the archaeological excavations, is presented, A Nikon camera with a fisheye lens and a smartphone camera have been used to survey the internal part of the cave, while an aerial drone has been employed for the external area. The two models have been georeferenced and scaled using GCPs acquired by a double frequency GNSS (GPS and GLONASS) receiver. A low-resolution DTM derived from a previous aerial laser scanning survey and the 3D models have been elaborated in CloudCompare environment to highlight the complete morphology of the cave and its surroundings.