Bio- and landscape diversity Theme 8 Theme

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Bio- and landscape diversity: Theme # 8 Theme 8: Landscape diversity • What is landscape diversity • Measuring landscape diversity • Mapping landscape diversity • Landscape fragmentation

Bio- and landscape diversity: Theme # 8 What is landscape diversity The landscape diversity is understood as the diversity of ecosystems composing the landscape. In the hierarchy of the levels of biodiversity the landscape diversity follows the ecosystem diversity. genetic diversity species diversity ecosystem diversity landscape diversity regional biodiversity global biodiversity The difference between ecosystem diversity and landscape diversity is that landscape diversity refers to the area, while the ecosystem diversity refers to the complexity of interactions between its elements. Ecosystem diversity as well as species, communities, and genetic diversity do not consider the territory. Few ecosystems – low landscape diversity. Many ecosystems – high landscape diversity.

Bio- and landscape diversity: Theme # 8 What is landscape diversity Series of maps showing the predicted changes in landscape pattern under the current land management. Landscape diversity often become lower if the current land management practices would not be corrected. In most cases the loss of landscape diversity means the degradation of landscape while it could not be used anymore for agriculture, forestry or for other human purposes.

Bio- and landscape diversity: Theme # 8 What is landscape diversity The landscape diversity depends on: 1 - the number of landscape elements within the area under study (the bigger the number is the more diverse the landscape would be) Number of landscape elements = 3 (simple landscape) Number of landscape elements = 20 (diverse landscape) 2 - the number of types of landscape elements within the area under study (the bigger the number of types of land elements is the more diverse the landscape would be) Number of types landscape elements = 4 (simple landscape) Number of types of landscape elements = 17 (diverse landscape)

Bio- and landscape diversity: Theme # 8 What is landscape diversity The landscape diversity depends on: 3 - The proportion of landscape elements of different types within the area under study (the more equally land elements are distributed within the landscape the more diverse it would be) One type of landscape elements dominates (simple landscape) Three types of landscape elements are equally distributed (diverse landscape) 4 – Configuration of land elements (the more complex the shapes of elements are the more diverse the landscape would be) Simple shape of (simple landscape) Complex shape of landscape elements (diverse landscape)

Bio- and landscape diversity: Theme # 8 What is landscape diversity Four dimensions of landscape diversity mentioned above (on two last pictures) describe four different aspects (sides) of landscape and have their names: Topological diversity refers to the number of landscape elements in a landscape Typological diversity refers to the number of types of landscape elements in a landscape Patterns diversity refers to the relative presence (per cent of an area) of various types of landscape elements in a landscape Configurational diversity refers to the complexity of borders between landscape elements in a landscape While all four dimensions of landscape diversity are regarded (and evaluated) altogether such feature of landscape Is often called as landscape complexity Landscape complexity = f (topological, typological, pattern, configurational diversity) Landscape with high complexity should have many landscape elements, many types of landscape elements, which are relatively equally distributed in a landscape and have complex shapes. :

Bio- and landscape diversity: Theme # 8 Measuring landscape diversity Landscape diversity could be measured (evaluated, quantified, quantitatively assessed). These estimates are widely used in landscape and regional planning and in mapping of landscape diversity. Various measures (indexes) of landscape diversity were proposed. Measures of topological landscape diversity: Patch Density (PD): expresses the number of patches within the entire reference unit on a per area basis (e. g. 100 ha). It is calculated as: PD is a Patch Density; n – is the number of landscape elements (pathces) in a landscape; S is the size (area) of a landscape Average size of a patch (AS): AS is a Average size of a landscape elements (patch); n – is the number of landscape elements (patches) in a landscape; si is the sizes of each particular landscape element in a landscape.

Bio- and landscape diversity: Theme # 8 Measuring landscape diversity Measures of typological landscape diversity: Number of classes (NC): expresses the number of types of landscape elements (patches). Even if a certain type of landscape element covers only the smallest possible area, it is counted. NC = 3 Measures of pattern landscape diversity: The Shannon Diversity Index (H) quantifies the diversity of landscape on two components: the number of different patch types and the proportional area distribution among patch types. It is calculated : H is The Shannon Diversity Index; m – is the number of landscape elements (patches) types in a landscape; si is the area (size) of each patch; S is the total area of a landscape NC = 3

Bio- and landscape diversity: Theme # 8 Measuring landscape diversity Measures of pattern landscape diversity: Landscape evenness (LE) measures how equally the landscape elements of various types are distributed among the landscape. It could be calculated using the formula: where H' is the Shannon diversity index and H' max is the maximum value of H', which is equal to ln. S: Landscape evenness index is constrained between 0 and 1. . Degree of coherence (C) Landscape division index (D)

Bio- and landscape diversity: Theme # 8 Measuring landscape diversity Measures of configurational landscape diversity: Edge Density (ED) or Perimeter/Area Ratio (PAR): An edge refers to the border between two landscape elements. Edge density (in m/ha) or alternatively Perimeter/Area Ratio equals the length (in m) of all borders between landscape elements divided by the total area of the landscape The index is calculated as: ED is the Edge Density, E is the total length of the borders between landscape elements; S is the total area 9 size) of the landscape. In contrast to patch density (PD), edge density (ED) takes the shape and the complexity of the patches into account. Edge density is a measurement of the complexity of the shapes of patches. Landscape dissection index (LDI) more complicated measure of landscape spatial configuration and is calculated as : LDI is the Landscape Dissection index; pi is the length of the borders of each type of landscape element; si is the area of each type of landscape element; S is the total area of the landscape.

Bio- and landscape diversity: Theme # 8 Mapping landscape diversity Maps of landscape diversity show the areas different in their diversity. These maps are used for identifying the areas with exceptionally rich landscape diversity as well as the areas where the diversity of landscape is low and thus needs to be enriched. The general approach for mapping of landscape diversity is to calculate the values of its particular measure (e. g. NC – number of classes, or PD – patch density, or any other ) for each of the reference units within the area under study. Normally, the reference units are chosen as a regular set of squares (quadrats) or hexagons covering all the area under study. The values of landscape diversity measure are then interpolated. Square lattice (grid) Hexagonal lattice

Bio- and landscape diversity: Theme # 8 Mapping landscape diversity In particular, maps of landscape diversity are used for creating the econets. The most diverse areas in landscape serves as the centres of biodiversity and as corridors connecting them into a net.

Bio- and landscape diversity: Theme # 8 Landscape fragmentation is a process of converting the natural vegetation cover into the arable lands, industrial sites, urban fabric so that natural ecosystems are preserved within separate patches. The landscape fragmentation is breaking up of large land area into smaller patches. Habitats which were once continuous become divided into separate fragments. After intensive clearing, the separate fragments tend to be very small islands isolated from each other by crop land, pasture, pavement, or even barren land. Landscape fragmentation influences many ecological patterns and processes and is mainly responsible for biological species extinction and biodiversity degradation. Fragmentation also increases the fragility of patches to external disturbance, for instance windstorm or drought. Forest fragmentation in southern Finland

Bio- and landscape diversity: Theme # 8 Landscape fragmentation Fragmentation of habitats: increases the number of areas, reduces the size of the areas increases the spatial isolation of the areas. As the result, the habitats become often too small for preserving local populations. Species, which cannot cross the areas between the remaining habitats, are then restrained on a high number of too small habitats. This reduces the probability of survival of a species in a region in the long term. In peri-urban environments, habitats are frequently separated by roads, settlements or intensively used agriculture land. These land-use types form a barrier for many species and entail the isolation of populations. Fragmented landscape: Areas painted in green – forests and other natural/seminatural vegetation; white colors – arable lands, villages and other man-made lands Phases of the landscape fragmentation (after R. Forman, 1995)

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