Are landscape pattern metrics suitable indicators of biodiversity in Temperate European agricultural landscapes
Résumé
The objective of this paper is to
investigate the relationship between landscape
pattern metrics and agricultural biodiversity at
the Temperate European scale, exploring the role
of thematic resolution and a suite of biological
and functional groups. Factor analyses to select
landscape-level metrics were undertaken on 25
landscapes classified at four levels of thematic
resolution. The landscapes were located within
seven countries. The different resolutions were
considered appropriate to taxonomic and functional
group diversity. As class-level metrics are
often better correlated to ecological response, the
landscape-level metric subsets gained through
exploratory analysis were additionally used to
guide the selection of class-level metric subsets.
Linear mixed models were then used to detect
correlations between landscape- and class-level
metrics and species richness values. Taxonomic
groups with differing requirements (plants, birds,
different arthropod groups) and also functional
arthropod groups were examined. At the coarse
scale of thematic resolution grain metrics (patch
density, largest patch index) emerged as rough
indicators for the different biological groups
whilst at the fine scale a diversity metric (e.g.
Simpson’s diversity index) was appropriate. The
intermediate thematic resolution offered most
promise for biodiversity monitoring. Metrics included
largest patch index, edge density, nearest
neighbour, the proximity index, circle and Simpson’s
diversity index. We suggest two possible
applications of these metrics in the context of
biodiversity monitoring and the identification of
biodiversity hot spots in European agricultural
landscapes.