Mapping data of a glacier cave inside the tidewater glacier Kongsvegen (western Svalbard, Norway)... more Mapping data of a glacier cave inside the tidewater glacier Kongsvegen (western Svalbard, Norway), collected on 06th of June 2021. Data was collected using a handheld GPS unit and a DistoX mapping device.
The use of unmanned aerial vehicles (UAV) for image based surface reconstruction has gained enorm... more The use of unmanned aerial vehicles (UAV) for image based surface reconstruction has gained enormous popularity in the last decade, not only in the study field of geomorphology, as technological improvements continue steadily. UAV Systems (UAS) have shown to be a cost-effective short- and close-range remote sensing alternative to classical manned aerial photogrammetry or LiDAR surveys. As geomorphic investigations concentrate on a multitude of purposes and processes different demands on accuracy and resolution arise. This study focuses on the error assessment of 3D point clouds (PCs) derived from high resolution image sets of four different UAV-systems: DJI Mavic Pro (MAV), DJI Phantom 4 Pro+ (P4P+), DJI Inspire 2 (I2) and Airborne-Robotics XR6 with Sony Alpha 6000 (XR6) with fixed 19 mm Sigma objective. We defined three classes to categorize the systems: “low-cost” ( 15000 €). In particular, we analyzed the influence of different flight patterns (parallel axes, cross-grid, cross-gr...
Since the end of the Little Ice Age (LIA), formerly glaciated areas have undergone considerable c... more Since the end of the Little Ice Age (LIA), formerly glaciated areas have undergone considerable changes in their morphodynamics due to external forces and system-internal dynamics. Using multi-temporal high-resolution digital elevation models (DEMs) from different remote sensing techniques such as historical digital aerial images and light detection and ranging (LiDAR), and the resulting DEMs of difference (DoD), spatial erosion and accumulation patterns can be analyzed in proglacial areas over several decades. In this study, several morphological sediment budgets of different test sites on lateral moraines and different long-term periods were determined, covering a total period of 49 years. The test sites show high ongoing morphodynamics, and therefore low vegetation development. A decrease as well as an increase of the mean annual erosion volume could be demonstrated at the different test sites. All test sites show a slope–channel coupling and a decrease in the efficiency of sedim...
The research project developed in this Thesis involves the application of close-range photogramme... more The research project developed in this Thesis involves the application of close-range photogrammetry based on the Structure from Motion (SfM) approach that allows reconstructing the 3D point cloud of the photographed object from a sequence of overlapping images taken with a common digital camera. Thanks to the characteristics of high portability of the equipment, flexibility of the method to reconstruct surface at different scale with high resolution, low-cost, and ease of use also for not expertise during both acquisition and processing phase, the SfM-photogrammetry is becoming a valid alternative to the range-based technology for remote sensing and monitoring of dynamic natural environments. The aim of this research was to test and validate the capability of a ground photogrammetric survey to reconstruct a surface by dealing the main practical issues of a ground acquisition and by highlighting the main error sources which may be present within the field data. Furthermore, the feas...
Satellite-based long-term observations of vegetation cover development in combination with recent... more Satellite-based long-term observations of vegetation cover development in combination with recent in-situ observations provide a basis to better understand the spatio-temporal changes of vegetation patterns, their sensitivity to climate drivers and thus climatic impact on proglacial landscape development. In this study we combined field investigations in the glacier forelands of Fürkele-, Zufall- and Langenferner (Ortles-Cevedale group/Eastern Italian Alps) with four different Vegetation Indices (VI) from Landsat scenes in order to test the suitability for modelling an area-wide vegetation cover map by using a Bayesian beta regression model (RStan). Since the model with the Normalized Difference Vegetation Index (NDVI) as predictor showed the best results, it was used to calculate a vegetation cover time series (1986–2019). The alteration of the proglacial areas since the end of the Little Ice Age (LIA) was analyzed from digital elevation models based on Airborne Laser Scanning (ALS...
The measurements of tree attributes required for forest monitoring and management planning, e.g.,... more The measurements of tree attributes required for forest monitoring and management planning, e.g., National Forest Inventories, are derived by rather time-consuming field measurements on sample plots, using calipers and measurement tapes. Therefore, forest managers and researchers are looking for alternative methods. Currently, terrestrial laser scanning (TLS) is the remote sensing method that provides the most accurate point clouds at the plot-level to derive these attributes from. However, the demand for even more efficient and effective solutions triggers further developments to lower the acquisition time, costs, and the expertise needed to acquire and process 3D point clouds, while maintaining the quality of extracted tree parameters. In this context, photogrammetry is considered a potential solution. Despite a variety of studies, much uncertainty still exists about the quality of photogrammetry-based methods for deriving plot-level forest attributes in natural forests. Therefore...
Mapping data of a glacier cave inside the tidewater glacier Kongsvegen (western Svalbard, Norway)... more Mapping data of a glacier cave inside the tidewater glacier Kongsvegen (western Svalbard, Norway), collected on 06th of June 2021. Data was collected using a handheld GPS unit and a DistoX mapping device.
The use of unmanned aerial vehicles (UAV) for image based surface reconstruction has gained enorm... more The use of unmanned aerial vehicles (UAV) for image based surface reconstruction has gained enormous popularity in the last decade, not only in the study field of geomorphology, as technological improvements continue steadily. UAV Systems (UAS) have shown to be a cost-effective short- and close-range remote sensing alternative to classical manned aerial photogrammetry or LiDAR surveys. As geomorphic investigations concentrate on a multitude of purposes and processes different demands on accuracy and resolution arise. This study focuses on the error assessment of 3D point clouds (PCs) derived from high resolution image sets of four different UAV-systems: DJI Mavic Pro (MAV), DJI Phantom 4 Pro+ (P4P+), DJI Inspire 2 (I2) and Airborne-Robotics XR6 with Sony Alpha 6000 (XR6) with fixed 19 mm Sigma objective. We defined three classes to categorize the systems: “low-cost” ( 15000 €). In particular, we analyzed the influence of different flight patterns (parallel axes, cross-grid, cross-gr...
Since the end of the Little Ice Age (LIA), formerly glaciated areas have undergone considerable c... more Since the end of the Little Ice Age (LIA), formerly glaciated areas have undergone considerable changes in their morphodynamics due to external forces and system-internal dynamics. Using multi-temporal high-resolution digital elevation models (DEMs) from different remote sensing techniques such as historical digital aerial images and light detection and ranging (LiDAR), and the resulting DEMs of difference (DoD), spatial erosion and accumulation patterns can be analyzed in proglacial areas over several decades. In this study, several morphological sediment budgets of different test sites on lateral moraines and different long-term periods were determined, covering a total period of 49 years. The test sites show high ongoing morphodynamics, and therefore low vegetation development. A decrease as well as an increase of the mean annual erosion volume could be demonstrated at the different test sites. All test sites show a slope–channel coupling and a decrease in the efficiency of sedim...
The research project developed in this Thesis involves the application of close-range photogramme... more The research project developed in this Thesis involves the application of close-range photogrammetry based on the Structure from Motion (SfM) approach that allows reconstructing the 3D point cloud of the photographed object from a sequence of overlapping images taken with a common digital camera. Thanks to the characteristics of high portability of the equipment, flexibility of the method to reconstruct surface at different scale with high resolution, low-cost, and ease of use also for not expertise during both acquisition and processing phase, the SfM-photogrammetry is becoming a valid alternative to the range-based technology for remote sensing and monitoring of dynamic natural environments. The aim of this research was to test and validate the capability of a ground photogrammetric survey to reconstruct a surface by dealing the main practical issues of a ground acquisition and by highlighting the main error sources which may be present within the field data. Furthermore, the feas...
Satellite-based long-term observations of vegetation cover development in combination with recent... more Satellite-based long-term observations of vegetation cover development in combination with recent in-situ observations provide a basis to better understand the spatio-temporal changes of vegetation patterns, their sensitivity to climate drivers and thus climatic impact on proglacial landscape development. In this study we combined field investigations in the glacier forelands of Fürkele-, Zufall- and Langenferner (Ortles-Cevedale group/Eastern Italian Alps) with four different Vegetation Indices (VI) from Landsat scenes in order to test the suitability for modelling an area-wide vegetation cover map by using a Bayesian beta regression model (RStan). Since the model with the Normalized Difference Vegetation Index (NDVI) as predictor showed the best results, it was used to calculate a vegetation cover time series (1986–2019). The alteration of the proglacial areas since the end of the Little Ice Age (LIA) was analyzed from digital elevation models based on Airborne Laser Scanning (ALS...
The measurements of tree attributes required for forest monitoring and management planning, e.g.,... more The measurements of tree attributes required for forest monitoring and management planning, e.g., National Forest Inventories, are derived by rather time-consuming field measurements on sample plots, using calipers and measurement tapes. Therefore, forest managers and researchers are looking for alternative methods. Currently, terrestrial laser scanning (TLS) is the remote sensing method that provides the most accurate point clouds at the plot-level to derive these attributes from. However, the demand for even more efficient and effective solutions triggers further developments to lower the acquisition time, costs, and the expertise needed to acquire and process 3D point clouds, while maintaining the quality of extracted tree parameters. In this context, photogrammetry is considered a potential solution. Despite a variety of studies, much uncertainty still exists about the quality of photogrammetry-based methods for deriving plot-level forest attributes in natural forests. Therefore...
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Papers by Livia Piermattei