Geography Reference
In-Depth Information
georelief development. The result of georelief reconstruction is a Digital Terrain
Model (DTM) representing the
base ground—
a surface without building,
trees, etc.
Aerial imagery is produced with DSM
s from the processed images—a surface
containing all the objects on the ground (houses, bridges, trees, etc.). DSM
processing is faster than hand digitizing the contour lines, but the resulting
model is affected by the quality of the input imagery.
The latest Digital Terrain Model of the Czech Republic of the 4th generation
(DMR 4G) data are used for representing the current state of the georelief—as
they represents a picture of natural or human activity modified terrain surface in
a digital form as heights of discrete points with X, Y, H coordinates in regular
5
'
5 m grid. These data were obtained using LIDAR technology (
Digital
Terrain Model of the Czech Republic of the 4th generation (DMR 4G) and
ˇ
´
ZK
).
The resulting DTMs from the year 1953 and 2012 are shown in Fig.
1
, where the
original state of the georelief and the current state is introduced—with a large water
dam and open-pit mine. This data requires special handling methods and has been
tested in Pacina et al. (
2012
) and Pacina et al. (
2013
).
Different types of analysis may be performed on the resulting surfaces—here we
may perform different analysis to delineate the areas with major georelief changes
and further apply volumetric analysis to compute the total volume of the added/
removed material from the area. The results of the differential analysis of DTMs are
presented in Fig.
1
. The dark green represents removed material (open-pit mine)
and the orange transported material (deposit, water dam). Detailed results and
analysis possibilities are presented in Pacina et al. (
2012
) and Pacina et al. (
2013
).
The project results will be offered to the public not only by a web-mapping
application but as well as an exhibition showing the results in reality. The
reconstructed DTMs (the original and current state) are printed using the ZPrinter
®
450 (a 3D printer) in tiles 20
25 cm, in the scale 1:50,000. The resulting tiles will
seamlessly cover the Most basin in areas with georelief change. Printed tiles of our
area of interest are presented in Fig.
1
.
Field Data Collection
A field survey is another reliable data source used for gathering data for our
information system. Several methods were used:
Unmanned Aerial Vehicle (UAV)—so called
drone
, can be used for carrying
different kinds of cameras (classic, multispectral, thermal). Results from UAV
survey may be orthophotos, DSMs, object 3D models, etc.
