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Abstract

Current laser scanning (Lidar, light detection and ranging) technologies span a wide range of survey extent and resolutions, from regional airborne Lidar mapping and terrestrial Lidar fi eld surveys to laboratory systems utilizing indoor three-dimensional (3D) laser scanners. Proliferation in Lidar technology and data collection enables new approaches for monitoring and analysis of landscape evolution. For example, repeat Lidar surveys that generate a time series of point cloud data provide an opportunity to transition from traditional, static representations of topography to terrain abstraction as a 3D dynamic layer. Three case studies are presented to illustrate novel techniques for landscape evolution analysis based on time series of Lidar data: (1) application of multiyear airborne Lidar surveys to a study of a dynamic coastal region, where the change is driven by eolian sediment transport, waveinduced beach erosion, and human intervention; (2) monitoring of vegetation growth and the impact of landscape structure on overland fl ow in an agricultural fi eld using terrestrial laser scanning; and (3) investigation of landscape design impacts on overland water fl ow and other physical processes using a tangible geospatial modeling system. The presented studies demonstrate new insights into landscape evolution in different environments that can be gained from Lidar scanning spanning 1.0-0.001 m resolutions with geographic information system analysis capabilities.

Quantifying the effects of terrestrial laser scanner settings and survey configuration on land surface roughness measurement

“…We tested several different interpolation algorithms, but ultimately spline with tension yielded the smallest rmse values (cf. Starek et al, 2011). The average rmse for the high-resolution data was 0.016 m, with a standard deviation of 0.002.…”

“…In order to gauge the relative accuracy of the TLS data we calculated the vertical offset of the 404 GPS points acquired in the cup interspaces relative to an interpolated surface for individual and combinations of point clouds. Following Starek et al (2011) we used spline with tension. The GPS points were converted into raster format to facilitate differencing with the corresponding cells on the point cloud-interpolated surfaces.…”

Viewshed simulation and optimization for digital terrain modelling with terrestrial laser scanning

“…Centred at 35°44.2ʹ N, 78°40.7ʹ W within the Piedmont region's eastern boundary of North Carolina (Figure 1), the SECREF comprises a catchment for two sub-watersheds. Dense grassland is the dominant land cover type in the field, but tillage and other agricultural practices are sometimes performed (Starek et al 2011). The experimental site is mainly used for the research of soil erosion processes and landscape modification triggered by significant overland flow events.…”

“…Landscapes undergo constant evolution through natural erosions and anthropogenic events (Dean and Dalrymple 2002;Starek et al 2011). It is more important nowadays than ever to effectively monitor the highly variable evolution processes and understand their nature in order to support decision-making with respect to human settlement, environmental conservation, ground and air transportation and so forth.…”

“…The advent of light detection and ranging (lidar) technology mounted in airborne and terrestrial platforms has made it possible to accurately and rapidly monitor dynamic terrain evolution (Mitasova et al 2010). Compared to airborne lidar, terrestrial lidar, more commonly referred to as terrestrial laser scanning (TLS), is advantageous for very high-resolution mapping of localized terrain providing sub-cm scanning resolutions and a few mm point measurement accuracies (Starek et al 2011). TLS has been widely adopted to examine landform dynamics (Feagin et al 2012;Guisado-Pintado, Jackson, and Rogers 2019) and ecological resilience at coastal zones (Nguyen et al 2018;Owers, Rogers, and Woodroffe 2018).…”