Geoscience Reference
In-Depth Information
9.3 Material and Methods
9.3.1 Historical Maps
Digitised historical maps were the basis for the representation of the landscape
change (Krováková & Bruna, 2007; Timár & Pišút, 2008; Timár et al., 2008;
Mikšovský & Zimová, 2007). On the one hand sheets of the 1st Military Survey
were used, which was accomplished between 1763 and 1785 in the Austro-
Hungarian monarchy. Sheets from this particular part of the monarchy were plotted
in 1785 (Kretschmer & Riedl, 2008). Especially concerning their colour these sheets
were high quality but to some extent there is a remarkable difference in terms of the
content (meadow turns to arable land at the sheet border, tracks stops abruptly, etc.)
of the individual sheets. On the other hand there were sheets available from the 2nd
MS (accomplished 1821-1869, particularly plotted in 1845). The quality of these
sheets varies strongly. Especially the southern most sheets are low grade concerning
colour. The central sheets have almost the same quality as the sheets from the 1780s.
The original northern-most sheets got lost and were obviously only available as bad
brown-coloured copies of the original. Content differences between the sheets were
not as serious and rather rare (for instance draw wells are missing completely in
the western sheets). Because of the fact, that it is not possible to rectify this kind of
data accurately into present-day coordinate systems (Timar et al., 2007; Cajthaml,
2007b) the maps were rectified manually via ground control points. To increase
the precision of rectification an already existing high-resolution laser-scan (LIDAR)
was used to build a digital terrain model (DTM) with a horizontal resolution of 17
and 4 cm accuracy in height (Bitenc, 2007). Military surveys on the whole concen-
trate very strongly on militarily relevant land marks. In this special case a lot of the
plotted small observation knolls can be accurately linked to uprisings in the DTM.
9.3.2 Current Land Cover Data
Current land cover data were derived from the official digital cadastral map (DCM,
which is constantly renewed) and SINUS land-cover data (Peterseil, et al. 2004).
Because of poor resolution and too common categories within these two datasets
additional data from various practical courses and field surveys were included
especially for displaying actual grassland areas properly.
9.3.3 Determination of Investigation Area
The investigation area has been defined as the extension area of the used DTM.
This area is restricted to a broad strip along the eastern shore of Lake Neusiedl up
to the Hanság on the Hungarian border. Figure 9.1 displays the extension of the
investigation area. Altogether the analysed area covers 317.18 km
2
. Different kinds
of overlapping nature protection areas can be found (see Table 9.1).
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