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S. Frank et al. 2010. A regionally adaptable approach of landscape assessment using landscape metrics
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such as economic wealth, ecological functioning and landscape aesthetics. Landscape evaluation
is realized at two assessment levels. The first level (a) provides an indicator based evaluation of
LUT- values with regard to each ecosystem service on a relative scale from 0 to 100. The
relative scale addresses the problem to provide a basis for comparing changes of various
ecosystem services, which each are expressed by different units and address different orders of
magnitudes. Regarding cell values, the LUT-values are corrected by integrating cell specific
attributes (soil, climate, topography) and the cell specific environment (neighbored LUT).
The here presented paper documents a second evaluation level (b). The assessment of landscape
patterns using landscape metrics (LMs) will provide the possibility to correct the result achieved
for the ecosystem service “ecological functioning” with regard to superior landscape structure
aspects. Aim of our study is to develop a scientifically and normative based system facilitating
quantification and assessment of the ecological functioning at landscape level.
2. Conceptual approach
For the usage of LMs as corrective for the ecological functioning of a landscape, relations
between landscape mosaic, ecological processes and ecosystem services need to be identified.
Landscape structure represents the interface between the land use that is influenced by natural
and cultural compounds on the one hand and ecological and functional landscape properties on
the other. Hence, quantification of landscape structure considering composition and
configuration of patches is of fundamental importance for an assessment of ecosystem services
(Zebisch et al. 2004).
LMs can be calculated at three spatial levels: patch level, class level and landscape level
(McGarigal and Marks 1995). To ensure an adequate quantification of the considered processes,
we mainly referred to class level. An aggregation of LUTs provides not only a spatial but also a
functional reference. This classification approach implies three functional groups:
(a) unsealed open space, e.g. Agricultural areas, Forest and semi natural areas, Wetlands;
(b) sealed areas, e.g. artificial areas, streets, rail tracks;
(c) degree of hemeroby.
Especially (c) is of importance because it considers function aspects of the landscape structure.
Six degrees of hemeroby are distinguished (Table 1). Each LUT was assigned to one degree of
hemeroby. Additionally, a superior aggregation into “natural” and “not natural” LUTs became
necessary to assess certain ecological parameters such as habitat connectivity. As no
“ahemerobe” LUTs are located in Europe (Steinhardt et al. 1999), this hemeroby class was not
considered for calculations.
Table 1: Classification of the human impact on ecosystems and the according degree of hemeroby and
naturalness (Blume and Sukopp 1976 -modified)
LMs describing the intensity of land use and the habitat connectivity, which are two of three
main evaluation parameters, are based on the hemeroby classification. The degree of hemeroby
is used for the Hemeroby Index. Habitat connectivity is based on the sub-classification into
“natural” and “not natural” LUTs. The third main indicator, biodiversity, is based on two
indices measuring the spatial diversity of a landscape. Figure 1 gives an overview of LMs,
indicators and main indicators that are used to evaluate the ecological functioning.
Figure 1: Hierarchical assessment scheme for the ecosystem service “ecological functioning”
3. Assessment of the ecological value
Figure 1 highlightens that intensity of land use, habitat connectivity and biodiversity are used as
main factors for evaluating the effect of the landscape structure on ecological functioning.
Intensity of land use and biodiversity are integrated into the evaluation by the use of “ecological
Forest Landscapes and Global Change-New Frontiers in Management, Conservation and Restoration. Proceedings of the IUFRO Landscape Ecology
Working Group International Conference, September 21-27, 2010, Bragança, Portugal. J.C. Azevedo, M. Feliciano, J. Castro & M.A. Pinto (eds.)
2010, Instituto Politécnico de Bragança, Bragança, Portugal.