1.1.2 Ground-based laser scanning
Compared with traditional methods (aerial photography, ground
photogrammetric survey, field studies), laser scanning has several
advantages. Very precise results make it possible to estimate the
intensity of slope processes, and estimate the age of landslide bodies
(Monserrat & Crosetto, 2008; Dunning et al. , 2009), to build
detailed three-dimensional models and evaluate the slope stability
(Viero et al. , 2010). One of the essential uses of ground-based
laser scanning is to study the dynamics of slope processes. The study of
relief dynamics requires repeated measurements of the object under study
and their comparison with previous data, which requires geodetically
accurate referencing provided by modern ground-based laser scanning
technologies (Barbarella et al. , 2015; Gafurov et al. ,
2016; Yermolaev et al. , 2018).
Fundamentally different technology for scanning results of
georeferencing was proposed in 2014 by a group of Polish researchers. A
network of ground control points was organized with the use of the
differential global positioning system (DGPS) (Kociuba et al. ,
2014). The georeference accuracy, taking into account the DGPS receiver
error, was 26 cm. In 2015, the same research team carried out laser
scanning to monitor gully processes in a relative coordinate system,
which led to an increase in the accuracy of scans adjustment by two
orders (Kociuba et al. , 2015). Similar studies were carried out
in 2008-2010 in Spain by the Jimenez-Peralvarez scientific team
(Palenzuela et al. , 2016) and by Swiss scientists under the
leadership of M. Franz in 2012 (Franz et al. , 2016). The
combination of different technologies made it possible to achieve
georeferencing accuracy within 11 mm in plan and 17 mm in height.
Studies of landslides near water bodies are mainly carried out on the
coasts of seas and oceans (Spreafico et al. , 2015). Few
scientific studies have been devoted to the monitoring of hazardous
processes on slopes bordering reservoirs. Several publications on the
Three Gorges Reservoir in China, created in 2003, stand out (Wanget al. , 2015; Nicu et al. , 2019; Zhang et al. ,
2020; Guo et al. , 2020). In contrast, in Russia, there are many
studies devoted to studying geomorphic processes on the banks of large
reservoirs, because of the large-scale construction of hydroelectric
power plants in the middle of the last century (Starodubtsev, 2012;
Babicheva & Rzetala, 2013; Kalinin et al. , 2015; Bondur et
al. , 2019; Mazaeva et al. , 2019; Nikonorova et al. ,
2019).