In: Wagner W., Szekely, B. (eds.): ISPRS TC VII Symposium - 100 Years ISPRS, Vienna, Austria, July 5-7, 2010, IAPRS, Vol. XXXVIII, Part 7B
visual photointerpretation whose aim is to identify individual
objects and assess their importance (Philipson, 1997, McGlone,
2004 in Jensen, 2006). Aerial photo interpretation starts from
visual perception related to objects of the outer world Ciolkosz,
Miszalski, Oledzki, 1999).
The displays of deep coal mining in the landscape were detected
using contact copies of archive black-and-white aerial photos
from the period of 1947 to 1995 (provided by the Military
Geography and Hydrometeorology Office in Dobruska) and a
coloured orthophoto from 2003 (map service of the Portal of the
Public Administration of the Czech Republic).
The surface consequences of hard coal deep mining are
characterized by the occurrence of anthropogenic landforms
directly related to mining (waste banks, submerged ground
subsidences, tailings ponds, manipulation areas etc.). Secondary
subsurface coal mining leads to the process of abandonment
(e.g. the transformation of continuous urban fabric into green
urban areas), the occurrence of reclamation areas aimed to deal
with the consequences of mining activity, or the construction of
communications.
2. DISPLAYS OF HARD COAL DEEP MINING
2.1 Primary displays
Hard coal deep mining is primarily manifested by
anthropogenic landforms directly related to mining activity.
These include post-mining landforms (waste banks, ground
subsidences) and industrial landforms (tailings ponds,
manipulation areas).
2.1.1 Waste banks: Waste banks represent convex
landforms whose area can reach from a few areas to tens of
hectares (Havrlant 1980). They originate as a result of the
deposition of extracted coal waste. The OKMD area includes
the following types of waste banks (Havrlant 1980): cone-
shaped waste banks, waste piles, plate-shaped waste banks,
terrace-like waste banks, flat waste piles or their combinations.
Active waste banks in the photos represent vegetation-free
surfaces with clearly visible contours (Figure 2). They are
generally found in the proximity of mine buildings.
Figure 2. Waste banks in (a) an aerial photo from 1947 (© MO
CR/GeoSI ACR) and (b) an aerial photo from 2003
Waste banks are reclaimed after waste piling is terminated
(Figure 3).
Figure 3. The part of reclaimed waste bank in 2003
2.1.2 Ground subsidences: Ground subsidences originate
as a result of the surface subsidence above the mined-out space
(Demek, 1988). It concerns flat subsidences whose size depends
on geological conditions, tectonics and the area and thickness of
coal-seams (Havrlant, 1980). The subsidences can be filled with
water. Submerged ground subsidences are displays of
unfavourable disturbance of the regime of surface and
subsurface waters the level of which has infiltrated above the
bottom of subsided terrain (Zapletal, 1969).
The occurrence of ground subsidences is therefore a primary
display of mining activity. Aerial photos help to interpret
particularly submerged ground subsidences that represent a
secondary display of undermining and that, to a large extent,
take part in the process of submerging. Unlike other water
surfaces they usually have an irregular broken shape (Figure 4).
Submerged ground subsidences positively affect ecological
value of landscape as they increase species diversity of the
territory. Their banks are occupied by wetland plant species,
rare invertebrates (e.g. specially protected dragonflies,
crayfishes, shells) and other important animal species.