Landscapes Forest and Global Change - ESA - Escola Superior ...

S. Frank et al. 2010. A regionally adaptable approach of landscape assessment using landscape metrics
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linking matrices” that allow for combining various LMs including their mutual impact (Bastian
and Schreiber 1999). Figure 2 illustrates the methodological approach. Values of the considered
LMs are assigned to five classes. “Hemeroby” that quantifies the degree of naturalness is one
factor for the determination of the intensity of land use (left part of Figure 2). For the
investigation of the second factor “landscape fragmentation”, two LMs get interlinked. The
Effective Mesh Size (M eff ) is a LM measuring the mean area of unsealed open area. A linkage
with the Total Core Area of natural LUTs yields a value of “landscape fragmentation” (right
part of Figure 2). The final value of the “Intensity of Land Use” can then be read off the linking
matrix (bottom part of Figure 2).
Figure 2: Exemplary application of ecological linking matrices for assessing the intensity of land use
For calculating intensity of land use and biodiversity, the same procedure is applied. For
considering different aspects of biodiversity at landscape level we considered two spatial
aspects. Shannon’s Diversity Index (SHDI) that reflects the compositional component (number
of patch types) as well as the structural component (distribution of classes) of landscapes, was
taken into account. Additionally, in order to quantify the spatial configuration of patch types,
the Interspersion and Juxtaposition Index (IJI) was chosen. Interlinking these two indices within
a linking matrix, statements on the variety of habitats can be made. For quantifying the third
factor habitat connectivity, the Cost Distance Method is used. This method allows measuring
functional connectivity of “natural” habitats (Zebisch et al. 2004). The basic assumption is that
“ecological costs” increase with increasing degree of hemeroby of raster cells that need to be
crossed for reaching other natural areas. The Moving-Window-method was then applied to
identify natural areas that might serve as “stepping stones” between core areas. The value of
habitat connectivity ranges from -10 to 10 in 5-point-steps (Table 2).
Table 2: Evaluation of the habitat connectivity
The normative background, which sets thresholds of LMs beyond expert knowledge, is given by
German laws and strategies (e.g. BMU 2007; BNatSchG 2010). Thresholds were set following
development targets. For example the degree of habitat connectivity mandatory shall be at least
10 % (§20(1) BNatSchG 2010). As ecologists criticize this value being too low (SRU 2000;
Krüsemann 2006), a positive evaluation starts at a percentage of >15 % of habitat connectivity.
Summarizing the results of all three factors gives the figure to which the preliminarily
calculated value for ecological functioning in Pimp Your Landscape should be increased or
reduced. It ranges from - 30 to + 30. Due to the relative evaluation scale of 0 to 100, the impact
of LMs as superior evaluation tool within Pimp Your Landscape is estimated to be significant.
4. Conclusion and outlook
Concerning landscape panning, LMs within Pimp Your Landscape provide an assessment tool
for the evaluation of functions and services that cannot easily be determined. The combination
of ecological linking matrices and traits of an additive model provided the possibility to
aggregate a large number of landscape characteristics to correct one macro-indicator (ecological
functioning). The here presented evaluation approach provides theoretical background for
further evaluation criteria such as aesthetics, water quality and economical wealth. For complex
methods evaluating the functionality of landscapes not only LMs but also further information is
necessary (Lang et al. 2009). Hence, besides a purely quantitative analysis of LMs, scientific
findings such as degrees of hemeroby are essential to make basic assumptions. Employing LMs
without any assumptions and restrictions would risk misinterpretations (Fortin et al. 2003). An
additional measure to avoid misinterpretations is the usage of sets of LMs(Lausch and Herzog
2002; Cushman et al. 2008). Due to local developed landscape characteristics, employing only
one LM could lead to an over- and under-estimation of determined characteristics.
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.