The Green Belt as a European Ecological Network strengths and gaps

Schlumprecht, H., Laube, J.
MONITORING BIODIVERSITY OF THE THURINGIAN GREEN BELT
Belt. The following text presents this concept and the results of the first survey rounds in the
years 2010 and 2011.
1.2 Concept Outline
The monitoring programme covers 30 monitoring areas. This number was chosen to
assure validity and representativeness on the one hand, and to meet long-term funding
possibilities on the other hand. The final number of 30 areas is the result of a power analysis
based on preliminary results in 2010. Power analysis is a statistical method to identify the
minimum required sample size to obtain meaningful results.
The monitoring consists of a spatially explicit and comprehensive survey of biotopes
(land use types and valuable biotopes for nature conservation, according to Article 30 of
Federal German Nature Conservation Law and the manual for the Thuringian biotope
mapping [2]). All areas of minor conservational value were noted as land use types solely. For
all valuable biotopes, a detailed documentation is given (biotope structure, land use, threats,
shrub cover, management proposals). A detailed evaluation (with 3 levels: excellent, good or
poor conditions) of the parameters habitat structure, plant species composition, and
impairments is given, and then summed up for a comprehensive evaluation of each biotope.
Additionally, a comprehensive list of characteristic and threatened plants (species lists
including an estimate of abundance) is compiled for each valuable biotope. The evaluation
scheme was developed with reference to the evaluation scheme for habitat types of the
Habitats Directive [3].
Furthermore, three animal groups are investigated. A survey of breeding birds is done
according to the German standard method for territorial bird mapping [4] with 5 survey dates.
The survey of butterflies and grasshoppers follows the German standard of butterfly
monitoring: 500 m long transect of 10 reaches, counting individuals at 4 survey dates (see
[5]). Zoological surveys were done in 7 selected monitoring areas. The number of 7 sites
again are a compromise between costs for field work, accuracy and limited funding. For each
species, the reproduction status is assessed. The evaluation is based only on confirmed and
probably reproducing species. The areas of valuable biotopes as well as land use types of
minor conservational value were mapped and digitized in a scale of 1:2500 on aerial
photographs using GIS (ArcGIS 9.3), detailed information on valuable biotopes were
documented in a database. One monitoring area can consist of up to 20 land use types and
valuable biotopes.
1.3 Selection of monitoring areas
The selection of monitoring areas followed several aims. Every natural geographic unit
should be represented with at least one area, and large natural geographic units with at least
two areas. Main biotope types should be represented in all the natural geographic units in
which they are common. Thirdly, it was aspired to represent different elevations of the
Thuringian Green Belt. Therefore, the 30 monitoring areas are scattered along the Thuringian
Green Belt (see Figure 1).
Within this framework, the monitoring areas should not represent the „best“ or „most
valuable“ sections of the Green Belt per natural geographic unit, but were chosen to give
reliable information of the actual state habitats and biotopes within the Green Belt. Therefore,
strongly degraded open land areas were included as monitoring sites, but areas of the Green
Belt completely covered by forests were not surveyed. The monitoring areas (2010 and 2011)
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