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S. Thorin et al.
17.1 Introduction
Landscape ecology is a multidisciplinary field that combines the spatial approach of
geography with functional ecology (Boström et al. 2011). Landscape ecology has
been widely applied in the terrestrial environment to understand the relationships
between spatial patterns and ecological processes at a range of spatial and temporal
scales (Wedding et al. 2011). But while landscape ecology started out as primarily
a terrestrial discipline, it is increasingly applied to explore organism–habitat relationships in aquatic environments. Initial studies applying landscape approaches to
tropical marine systems indicate that landscape structure (cover and pattern of surrounding habitat types) likely play an important role in determining fish community
composition, abundance and species richness (Yeager et al. 2011). As highlighted by
Pittman et al. (2011), landscape ecology concepts have recently emerged as theoretical and analytical frameworks that are equally useful for evaluating the ecological
consequences of spatial patterns and structural changes in the submerged landscapes
of coastal ecosystems. Thus, since the early 1990s, the landscape ecology approach
has been applied in several coastal subtidal and intertidal biogenic habitats across a
range of spatial scales (Boström et al. 2011).
A submerged landscape, called seascape, is defined as a spatially heterogeneous
area of coastal environment (i.e. intertidal, brackish). Seascape structure is commonly represented as a patch matrix, with focal patches (e.g. vegetation) viewed as
‘islands’ embedded in a matrix (e.g. sediment) that affect animal movements and survival depending on relative isolation (Boström et al. 2011). Measurement of spatial
patterns plays a central role in monitoring environmental change and for studying
the multi-scale processes that drive organism distributions and biodiversity (Pittman
et al. 2011). Moreover spatial heterogeneity is now recognized as a central driver to
many ecological processes (Wedding et al. 2011; Yeager et al. 2011). Spatial pattern
metrics offer great potential for ecological research and environmental management
in marine systems (Wedding et al. 2011).
Habitat structure likely drives a large part of spatial variability in the distribution
and abundance of Mediterranean organisms, especially when abundance is assessed
at small spatial scales. Habitat complexity can thus be measured at each scale using
different variables (e.g. number of boulders classified by size, rugosity, etc.; see
Ruitton et al. 2000). If we consider habitat structure from a functional perspective,
such that habitat refers to any physical or biological environmental attribute that
offers some resource like food or shelter to the organisms of interest at a given
scale, then it is pertinent to ask what features of this habitat are important to those
organisms, and what the responses of those organisms are to the spatio-temporal
heterogeneity of a feature of this habitat (Garcia-Charton et al. 2000).
One of the most important and characteristic habitats of the north-western Mediterranean coastal areas is the rocky substrata (Harmelin 1987). Mediterranean rocky
bottoms are generally formed by boulders of several sizes (from small stones to huge
blocks) resulting from coastal erosion, flagstones, plates or large areas of bedrock
with varying degrees of architectural complexity. The complexity of coastal rocky
S. Thorin et al.
17.1 Introduction
Landscape ecology is a multidisciplinary field that combines the spatial approach of
geography with functional ecology (Boström et al. 2011). Landscape ecology has
been widely applied in the terrestrial environment to understand the relationships
between spatial patterns and ecological processes at a range of spatial and temporal
scales (Wedding et al. 2011). But while landscape ecology started out as primarily
a terrestrial discipline, it is increasingly applied to explore organism–habitat relationships in aquatic environments. Initial studies applying landscape approaches to
tropical marine systems indicate that landscape structure (cover and pattern of surrounding habitat types) likely play an important role in determining fish community
composition, abundance and species richness (Yeager et al. 2011). As highlighted by
Pittman et al. (2011), landscape ecology concepts have recently emerged as theoretical and analytical frameworks that are equally useful for evaluating the ecological
consequences of spatial patterns and structural changes in the submerged landscapes
of coastal ecosystems. Thus, since the early 1990s, the landscape ecology approach
has been applied in several coastal subtidal and intertidal biogenic habitats across a
range of spatial scales (Boström et al. 2011).
A submerged landscape, called seascape, is defined as a spatially heterogeneous
area of coastal environment (i.e. intertidal, brackish). Seascape structure is commonly represented as a patch matrix, with focal patches (e.g. vegetation) viewed as
‘islands’ embedded in a matrix (e.g. sediment) that affect animal movements and survival depending on relative isolation (Boström et al. 2011). Measurement of spatial
patterns plays a central role in monitoring environmental change and for studying
the multi-scale processes that drive organism distributions and biodiversity (Pittman
et al. 2011). Moreover spatial heterogeneity is now recognized as a central driver to
many ecological processes (Wedding et al. 2011; Yeager et al. 2011). Spatial pattern
metrics offer great potential for ecological research and environmental management
in marine systems (Wedding et al. 2011).
Habitat structure likely drives a large part of spatial variability in the distribution
and abundance of Mediterranean organisms, especially when abundance is assessed
at small spatial scales. Habitat complexity can thus be measured at each scale using
different variables (e.g. number of boulders classified by size, rugosity, etc.; see
Ruitton et al. 2000). If we consider habitat structure from a functional perspective,
such that habitat refers to any physical or biological environmental attribute that
offers some resource like food or shelter to the organisms of interest at a given
scale, then it is pertinent to ask what features of this habitat are important to those
organisms, and what the responses of those organisms are to the spatio-temporal
heterogeneity of a feature of this habitat (Garcia-Charton et al. 2000).
One of the most important and characteristic habitats of the north-western Mediterranean coastal areas is the rocky substrata (Harmelin 1987). Mediterranean rocky
bottoms are generally formed by boulders of several sizes (from small stones to huge
blocks) resulting from coastal erosion, flagstones, plates or large areas of bedrock
with varying degrees of architectural complexity. The complexity of coastal rocky