MAPPING LANDSCAPE DIVERSITY ON THE BASIS OF LAND COVER DATA

E.B. Bielecka

Institute of Geodesy and Cartography

elzbieta.bielecka@igik.edu.pl

 

Landscape represents the complex interaction between human societies and the natural environment. Portraying landscape on the basis of land cover category is a simple and aggregated way because the land cover structure together with the relief are mainly recognisable as a landscape.

This paper presents work carried out at the Institute of Geodesy and Cartography on the basis of general assumptions made by European Commission in the report From Land Cover Data to Landscape Diversity. This is an attempt to adjust the European methodology for setting up landscape indicators to Polish environment as well as explore potentialities and limits to use CORINE Land Cover data to portrayal diversity of Polish landscape. The investigation presented focuses on the following questions:

  1. What type of reference units could be the most appropriate for retrieving landscape metrics?
  2. How can landscape metrics portray the spatial structure of landscape?
  3. Are the metrics sensible enough to reveal changes in landscape affected by land cover changes?

As a single indicator which describes all aspects of landscape structure does not exist five metrics were chosen and investigated in depth: Number of Patches, Patch Density, Edge Density, Shannon Diversity Index and Interspersion and Juxtaposition Index. Analysis conducted shows that NP, PD and ED are correlated, so that is why only one matrix is usually enough. The contrast between regions is more pronounced by Shannon Diversity Index and Edge Density. Whereas Interspersion and Juxtaposition Index stresses diversification of the landscape. The matrices could also portray changes in the landscape because appearance as well as disappearance of land cover polygons (patches) results in different values of indices

The CORINE Land Cover (CLC) databases were the source for computing landscape metrics. These inventories are based on satellite images as the primary data source. CLC is a coherent and standardised geodataset with 25 ha minimum mapping unit. However we should remember that the mapping unit and the methodology of attributing to each polygon the dominant type of land cover significantly influence the value of indices.

To conclude landscape metrics computed on the basis of CORINE Land Cover data allow to complement the stock of knowledge about landscape and are useful tool for preserving and sustaining landscape diversity.