Monitoring vegetation and land use quality along the ruraleurban gradient in a Mediterranean region Luca Salvati a, b, * , Marco Zitti b, c a Italian Council for Research in Agriculture, Centre for Plant-Soil Relationships (CRA-RPS), Via della Navicella 2-4, I-00184 Rome, Italy b Department of Methodologies and Modeling for the Study of Territory, Economy and Finance, University of Rome ‘La Sapienza’, Via del Castro Laurenziano 9, I-00161 Rome, Italy c Italian Council for Research in Agriculture, Unit of Climatology and Meteorology Applied to Agriculture (CRA-CMA), Via del Caravita 7a, I-00186 Rome, Italy Keywords: Landscape changes Urban sprawl Rome Southern Europe abstract This paper illustrates a methodology to quantify vegetation quality and its possible degradation in a large ‘shrinking’ Mediterranean city. Vegetation quality was estimated at three years (1960, 1990, 2006) in the Nuts-3 prefecture of Rome, central Italy (5355 km 2 ) through the analysis of comparable land cover maps. The aims of this work are to assess how ‘compact growth’ and ‘sprawl’ impact on vegetation quality, and to monitor the territorial disparities observed in the vegetation quality as caused by urbanization and land use polarization. Built-up areas covered 3.3% and 12.9% of the investigated area in 1960 and 2006, respectively, with a dispersed to compact urban surface ratio passing from 1.2 to 1.9. Vegetation quality increased slightly during the investigated period with a diverging trend between urban and rural areas. As a consequence, territorial disparities in the same variable grew due to low-density urban diffusion in lowlands and depopulation with land abandonment and natural forestation in mountain areas. Ó 2011 Elsevier Ltd. All rights reserved. Introduction Urbanization is a process of settlement diffusion that involves different factors that gradually end up changing spatial structures and creating new landscape patterns (Antrop, 2004). Urbanization reflects cultural and sociological challenges caused by the trans- formation of rural life styles into urban-like ones, inducing changes in the way man uses his environment and in the ecological func- tioning of the landscape (Alberti, 2005; Antrop, 2000, 2006; Conway & Lathrop, 2005; Johnson, 2001; McDonnell et al., 1997; Pickett et al., 2001). Urbanization acts in different ways according to the geograph- ical and geopolitical position of the region, and thus it should be approached considering the specific territorial and historical context in which particular urban forms shape cities (Antrop, 2005; Bruegmann, 2005; Richardson & Chang-Hee, 2004). Landscapes created by the transformation of the countryside around urban centres are referred to as ‘periurban’ landscapes and are charac- terized by a wide variety of land uses, which is expressed in a highly-fragmented morphology (Antrop, 2004). In periurban regions new elements and structures are superimposed upon the traditional landscape, that tends to become functionally homoge- neous although with a high structural heterogeneity. This process of landscape ‘homologation’ was largely due to the polarization in areas with different land uses caused by urban expansion (e.g. Salvati & Sabbi, 2011). Urban sprawl is regarded as a relatively recent process in Europe, especially in southern Europe (see Gargiulo Morelli & Salvati, 2010 and references therein). Traditionally, Mediterranean cities experi- enced a rapid compact growth till 1990s (Leontidou,1990). After this period, a low-density expansion was observed especially in large urban areas (Chorianopoulos, Pagonis, Koukoulas, & Drymoniti, 2010). The recent Mediterranean patterns of urban development impose to rethink the impact of ‘dense’ and ‘dispersed’ growth on landscape transformations. This dichotomy has sometimes related the opposition between diffused ‘green cities’ and high-density, compact cities (Jim, 2004) to the choice between urban desir- ability and suburban livability (Neuman, 2005). From the environ- mental point of view, trade-offs have been pointed out between outer land preservation and environmental quality within dense and diffused cities (Allen, 2003; Bolound & Hunhammar, 1999; Garcia & Riera, 2003). Sprawl-driven landscape changes have caused the depletion of heritage values and land resources (Antrop, 2000, 2004; Chorianopoulos et al., 2010; Economidou, 1993). The loss of arable lands, olive groves, vineyards, and annual crop is the most visible * Corresponding author. Italian Council for Research in Agriculture, Centre for Plant-Soil Relationships (CRA-RPS), Via della Navicella 2-4, I-00184 Rome, Italy. Fax: þ39 06 700 5711. E-mail address: luca.salvati@uniroma1.it (L. Salvati). Contents lists available at SciVerse ScienceDirect Applied Geography journal homepage: www.elsevier.com/locate/apgeog 0143-6228/$ e see front matter Ó 2011 Elsevier Ltd. All rights reserved. doi:10.1016/j.apgeog.2011.09.002 Applied Geography 32 (2012) 896e903