A Remote Field Course Implementing High-Resolution Topography Acquisition and Applications Applied to Geomorphology

Mapping Intimacies ◽

10.5194/gc-2021-26 ◽

2021 ◽

Author(s):

Sharon Bywater-Reyes ◽

Beth Pratt-Sitaula

Keyword(s):

High Resolution ◽

Data Collection ◽

Structure From Motion ◽

Laser Scanning ◽

Earth Science ◽

Terrestrial Laser Scanning ◽

Airborne Lidar ◽

Earth Surface ◽

University Of Northern Colorado ◽

The University

Abstract. The course "Geoscience Field Issues Using High-Resolution Topography to Understand Earth Surface Processes" was originally intended to be conducted in-person with both field data collection and analysis to meet the "field" component of the University of Northern Colorado's Earth Science degrees (Environmental and Geology). With the 2020 world pandemic and cancellation of most in-person activities for 2020, the course was adapted for 100 % online implementation with an optional one-day field campaign. To prepare for the changed delivery model, UNAVCO and the University of Northern Colorado collected GNSS data, drone imagery for use in structure from motion, and terrestrial laser scanning from a site near Greeley, Colorado USA on the Cache la Poudre River. These data were used in mock field campaigns and real analyses implemented by students virtually through Zoom and Canvas. The objective of the course is to train students in manual and remote sensing methods of topographic data collection, including 1) GPS/GNSS surveys, 2) structure from motion (SfM), and 3) ground-based (terrestrial laser scanning, TLS) and airborne LiDAR. Course content focused on earth-surface process applications, but could be adapted to other applications. This was taught workshop style with the bulk of the instruction and application occurring within a 2-week period during the summer. Students from throughout North America attended the course, most meeting Field Camp requirements required for graduation. Despite the challenging conditions, students met the majority of the National Association of Geoscience Teachers’ Field Capstone Learning Outcomes.

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MONITORING BLUFF EROSION RATES USING TERRESTRIAL LASER SCANNING AND STRUCTURE-FROM-MOTION PHOTOGRAMMETRY ON MINNESOTA'S NORTH SHORE STREAMS

10.1130/abs/2017am-305956 ◽

2017 ◽

Author(s):

Elizabeth R. Brown ◽

◽

Karen B. Gran

Keyword(s):

Structure From Motion ◽

Laser Scanning ◽

Terrestrial Laser Scanning ◽

Erosion Rates ◽

North Shore ◽

Bluff Erosion

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MONITORING BLUFF EROSION RATES USING TERRESTRIAL LASER SCANNING AND STRUCTURE-FROM-MOTION PHOTOGRAMMETRY ON MINNESOTA'S NORTH SHORE STREAMS

10.1130/abs/2018nc-312932 ◽

2018 ◽

Author(s):

Elizabeth R. Brown ◽

◽

Karen B. Gran

Keyword(s):

Structure From Motion ◽

Laser Scanning ◽

Terrestrial Laser Scanning ◽

Erosion Rates ◽

North Shore ◽

Bluff Erosion

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Melite Civitas Romana in 3D: Virtualization Project of the Archaeological Park and Museum of the Domus Romana of Rabat, Malta

Open Archaeology ◽

10.1515/opar-2020-0126 ◽

2021 ◽

Vol 7 (1) ◽

pp. 51-83

Author(s):

Davide Tanasi ◽

Stephan Hassam ◽

Kaitlyn Kingsland ◽

Paolo Trapani ◽

Matthew King ◽

...

Keyword(s):

Laser Scanning ◽

Structured Light ◽

Terrestrial Laser Scanning ◽

Archaeological Site ◽

South Florida ◽

Virtual Museum ◽

Current State ◽

Structured Light Scanning ◽

The University ◽

Archaeological Excavations

Abstract The archaeological site of the Domus Romana in Rabat, Malta was excavated almost 100 years ago yielding artefacts from the various phases of the site. The Melite Civitas Romana project was designed to investigate the domus, which may have been the home of a Roman Senator, and its many phases of use. Pending planned archaeological excavations designed to investigate the various phases of the site, a team from the Institute for Digital Exploration from the University of South Florida carried out a digitization campaign in the summer of 2019 using terrestrial laser scanning and aerial digital photogrammetry to document the current state of the site to provide a baseline of documentation and plan the coming excavations. In parallel, structured light scanning and photogrammetry were used to digitize 128 artefacts in the museum of the Domus Romana to aid in off-site research and create a virtual museum platform for global dissemination.

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Terrestrial Laser Scanning for Vegetation Analyses with a Special Focus on Savannas

Remote Sensing ◽

10.3390/rs13030507 ◽

2021 ◽

Vol 13 (3) ◽

pp. 507

Author(s):

Tasiyiwa Priscilla Muumbe ◽

Jussi Baade ◽

Jenia Singh ◽

Christiane Schmullius ◽

Christian Thau

Keyword(s):

Remote Sensing ◽

Vegetation Structure ◽

Laser Scanning ◽

Spatial Scales ◽

Terrestrial Laser Scanning ◽

Point Clouds ◽

Parameter Extraction ◽

Airborne Lidar ◽

Special Focus ◽

Vegetation Parameter

Savannas are heterogeneous ecosystems, composed of varied spatial combinations and proportions of woody and herbaceous vegetation. Most field-based inventory and remote sensing methods fail to account for the lower stratum vegetation (i.e., shrubs and grasses), and are thus underrepresenting the carbon storage potential of savanna ecosystems. For detailed analyses at the local scale, Terrestrial Laser Scanning (TLS) has proven to be a promising remote sensing technology over the past decade. Accordingly, several review articles already exist on the use of TLS for characterizing 3D vegetation structure. However, a gap exists on the spatial concentrations of TLS studies according to biome for accurate vegetation structure estimation. A comprehensive review was conducted through a meta-analysis of 113 relevant research articles using 18 attributes. The review covered a range of aspects, including the global distribution of TLS studies, parameters retrieved from TLS point clouds and retrieval methods. The review also examined the relationship between the TLS retrieval method and the overall accuracy in parameter extraction. To date, TLS has mainly been used to characterize vegetation in temperate, boreal/taiga and tropical forests, with only little emphasis on savannas. TLS studies in the savanna focused on the extraction of very few vegetation parameters (e.g., DBH and height) and did not consider the shrub contribution to the overall Above Ground Biomass (AGB). Future work should therefore focus on developing new and adjusting existing algorithms for vegetation parameter extraction in the savanna biome, improving predictive AGB models through 3D reconstructions of savanna trees and shrubs as well as quantifying AGB change through the application of multi-temporal TLS. The integration of data from various sources and platforms e.g., TLS with airborne LiDAR is recommended for improved vegetation parameter extraction (including AGB) at larger spatial scales. The review highlights the huge potential of TLS for accurate savanna vegetation extraction by discussing TLS opportunities, challenges and potential future research in the savanna biome.

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On the potential of very high-resolution repeat DEMs in glacial and periglacial environments

The Cryosphere ◽

10.5194/tc-4-53-2010 ◽

2010 ◽

Vol 4 (1) ◽

pp. 53-65 ◽

Cited By ~ 69

Author(s):

J. Abermann ◽

A. Fischer ◽

A. Lambrecht ◽

T. Geist

Keyword(s):

High Resolution ◽

Laser Scanning ◽

Airborne Lidar ◽

Primary Data ◽

Glacier Area ◽

Airborne Laser ◽

Multi Temporal ◽

Rock Glaciers ◽

Data Source ◽

Very High

Abstract. The potential of high-resolution repeat DEMs was investigated for glaciological applications including periglacial features (e.g. rock glaciers). It was shown that glacier boundaries can be delineated using airborne LIDAR-DEMs as a primary data source and that information on debris cover extent could be extracted using multi-temporal DEMs. Problems and limitations are discussed, and accuracies quantified. Absolute deviations of airborne laser scanning (ALS) derived glacier boundaries from ground-truthed ones were below 4 m for 80% of the ground-truthed values. Overall, we estimated an accuracy of +/−1.5% of the glacier area for glaciers larger than 1 km2. The errors in the case of smaller glaciers did not exceed +/−5% of the glacier area. The use of repeat DEMs in order to obtain information on the extent, characteristics and activity of rock glaciers was investigated and discussed based on examples.

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Combined Use of Terrestrial Laser Scanning and UAV Photogrammetry in Mapping Alpine Terrain

Remote Sensing ◽

10.3390/rs11182154 ◽

2019 ◽

Vol 11 (18) ◽

pp. 2154 ◽

Cited By ~ 6

Author(s):

Ján Šašak ◽

Michal Gallay ◽

Ján Kaňuk ◽

Jaroslav Hofierka ◽

Jozef Minár

Keyword(s):

High Resolution ◽

Point Cloud ◽

Laser Scanning ◽

Terrestrial Laser Scanning ◽

Point Clouds ◽

Mutual Orientation ◽

Close Range Photogrammetry ◽

Combined Use ◽

Wide Range ◽

Close Range

Airborne and terrestrial laser scanning and close-range photogrammetry are frequently used for very high-resolution mapping of land surface. These techniques require a good strategy of mapping to provide full visibility of all areas otherwise the resulting data will contain areas with no data (data shadows). Especially, deglaciated rugged alpine terrain with abundant large boulders, vertical rock faces and polished roche-moutones surfaces complicated by poor accessibility for terrestrial mapping are still a challenge. In this paper, we present a novel methodological approach based on a combined use of terrestrial laser scanning (TLS) and close-range photogrammetry from an unmanned aerial vehicle (UAV) for generating a high-resolution point cloud and digital elevation model (DEM) of a complex alpine terrain. The approach is demonstrated using a small study area in the upper part of a deglaciated valley in the Tatry Mountains, Slovakia. The more accurate TLS point cloud was supplemented by the UAV point cloud in areas with insufficient TLS data coverage. The accuracy of the iterative closest point adjustment of the UAV and TLS point clouds was in the order of several centimeters but standard deviation of the mutual orientation of TLS scans was in the order of millimeters. The generated high-resolution DEM was compared to SRTM DEM, TanDEM-X and national DMR3 DEM products confirming an excellent applicability in a wide range of geomorphologic applications.

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Terrestrial laser scanning and structure-from-motion photogrammetry concordance analysis for describing the surface layer of gravel beds

Progress in Physical Geography Earth and Environment ◽

10.1177/0309133318822966 ◽

2019 ◽

Vol 43 (2) ◽

pp. 260-281 ◽

Cited By ~ 2

Author(s):

Andrew J Neverman ◽

Ian C Fuller ◽

Jon N Procter ◽

Russell G Death

Keyword(s):

Surface Layer ◽

Structure From Motion ◽

Laser Scanning ◽

Terrestrial Laser Scanning ◽

Point Clouds ◽

Survey Method ◽

Gravel Beds ◽

Non Invasive ◽

Sampling Biases

Terrestrial laser scanning (TLS) and structure-from-motion photogrammetry (SfMp) offer rapid, non-invasive surveying of in situ gravels. Numerous studies have used the point clouds derived from TLS or SfMp to quantify surface layer characteristics, but direct comparison of the methods for grain-scale analysis has received relatively little attention to date. Comparing equivalent products of different data capture methods is critical as differences in errors and sampling biases between the two methods may produce different outputs, effecting further analysis. The sampling biases and errors related to SfMp and TLS lead to differences in the point clouds produced by each method. The metrics derived from the point clouds are therefore likely to differ, potentially leading to different inputs for entrainment threshold models, different trends in surface layer development being identified and different trajectories for physical processes and habitat quality being predicted. This paper provides a direct comparison between TLS and SfMp surveys of an exposed gravel bar for three different survey periods following inundation and reworking of the bar surface during high flow events. The point clouds derived from the two methods are used to describe changes in the character of the surface layer between bar inundation events, and comparisons are made with descriptions derived from conventional pebble counts. The results found differences in the metrics derived using each method do exist, but the grid resolution used to detrend the surfaces and identify spatial variations in surface layer characteristics had a greater impact than survey method. Further research is required to understand the significance of these variations for quantifying surface texture and structure and for predicting entrainment thresholds and transport rates.

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