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Landscape heterogeneity (the composition and configuration of matrix habitats) plays a major role in shaping species communities in wooded-agricultural landscapes. However, few studies consider the influence of different types of semi-natural and linear habitats in the matrix, despite their known ecological value for biodiversity.\ud Objective To investigate the importance of the composition and configuration of matrix habitats for woodland carabid communities and identify whether specific landscape features can help to maintain long-term populations in wooded-agricultural environments.\ud Methods Carabids were sampled from woodlands in\ud 36 tetrads of 4 km2 across southern Britain. Landscape\ud heterogeneity including an innovative representation\ud of linear habitats was quantified for each tetrad.\ud Carabid community response was analysed using ordination methods combined with variation partitioning and additional response trait analyses.\ud Results Woodland carabid community response was trait-specific and better explained by simultaneously considering the composition and configuration of matrix habitats. Semi-natural and linear features provided significant refuge habitat and functional connectivity. Mature hedgerows were essential for slow-dispersing carabids in fragmented landscapes. Species commonly associated with heathland were correlated with inland water and woodland patches despite widespread heathland conversion to agricultural land, suggesting that species may persist for some decades when elements representative of the original habitat are retained following landscape modification.\ud Conclusions Semi-natural and linear habitats have\ud high biodiversity value. Landowners should identify\ud features that can provide additional resources or\ud functional connectivity for species relative to other\ud habitat types in the landscape matrix. Agri-environment\ud options should consider landscape heterogeneity to identify the most efficacious changes for biodiversity.

The work presented in this report is part of the effort to define the landscape state and diversity indicator in the\ud frame of COM (2006) 508 “Development of agri-environmental indicators for monitoring the integration of\ud environmental concerns into the common agricultural policy”. The Communication classifies the indicators\ud according to their level of development, which, for the landscape indicator is “in need of substantial\ud improvements in order to become fully operational”. For this reason a full re-definition of the indicator has been\ud carried out, following the initial proposal presented in the frame of the IRENA operation (“Indicator Reporting on\ud the Integration of Environmental Concerns into Agricultural Policy”). The new proposal for the landscape state\ud and diversity indicator is structured in three components: the first concerns the degree of naturalness, the\ud second landscape structure, the third the societal appreciation of the rural landscape. While the first two\ud components rely on a strong bulk of existing literature, the development of the methodology has made evident\ud the need for further analysis of the third component, which is based on a newly proposed top-down approach.\ud This report presents an in-depth analysis of such component of the indicator, and the effort to include a social\ud dimension in large scale landscape assessment.