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Sensitivity to climate change and anthropogenic disturbance is a typical feature of Mediterranean forests growing under dynamic and manipulated environmental conditions. In the present study, a large sample of stone pines (Pinus pinea L.) was analyzed in five sites of Castelporziano and Castelfusano forests (Rome, central Italy) to assess tree-growth variability with the aim to derive information on long-term climatic trends possibly reflected in the radial growth response. The multivariate exploratory analysis of tree ring widths, which were standardized to remove the age trend, showed a marked spatial variability among sites and a heterogeneous time pattern that allows for the classification of the investigated years into three homogeneous groups : 1964: -1974: , 1975: -1997: , and 1998: . The years 1975: and 1998 were identified as the candidate break points in the local climate regime. Coherence of the 1998 break point was verified by comparing two time intervals (1981-1997 and 1998-2011) of the meteorological time series of precipitation and temperatures available for Castelporziano station. Results indicate a significant shift toward aridity and warming in the area supporting the information obtained from the analysis of dendro-chronological time series. Implications of the spatio-temporal monitoring of climate variations through indirect sources are discussed in the light of conservation of the residual pristine forest of Castelporziano taken as a paradigmatic example for other Mediterranean coastal forests.

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Summer precipitation and temperature regimes have been compared along the coastal-inland gradient in three sites (Tor Paterno and Castello in Castelporziano forest and Collegio Romano in inner Rome, central Italy) during the last 15 years (1999)(2000)(2001)(2002)(2003)(2004)(2005)(2006)(2007)(2008)(2009)(2010)(2011)(2012)(2013). Soil water budget using rainfall, evapotranspiration and maximum water capacity of the soil was calculated according to Thornthwaite-Mather approach for the two forest sites. Meteorological conditions during the dry season were found significantly different in the three sites with minimum temperatures increasing from the coastal site (Tor Paterno) to the inland area (Castello and Rome). Maximum temperatures showed a less marked coastal-inland gradient. Cumulative summer rainfalls (accounting for less than the 10 % of annual precipitation) were comparable in the three sites along with a high variability. Although soil water budget variables (available water content and water deficit) were similar in the two forest sites, the aridity index was higher in the inland site than in the coastal site. Despite based on a relatively short climatic time-series, implications of the climate variations observed along the coastalinland gradient in Castelporziano are discussed in the light of conservation of the residual pristine flat oakwood stands and the traditional agro-forest landscape mosaic.

The present study assesses how urban growth impacted landscape composition, structure and diversity in peri-urban Rome, central Italy, during the last 60 years (1949–2008). The spatial distribution and fragmentation of nine land-use classes derived from comparable digital maps covering the whole study area (1500 km2) were assessed by computing a total of 27 metrics using a relational approach based on exploratory data analysis. Landscape transformations were explored through hierarchical clustering applied on the selected landscape metrics. Our results indicate the increased fragmentation of peri-urban landscape over the study interval. Especially vineyards, arable land and pastures underwent patch fragmentation. This process was reflected into smaller ‘core’ areas compared with the remaining non-urban uses of land (woodland, olive groves). A negative relation between class area and patchiness was observed for all classes with the exception of forests and olive groves. Policies aimed at contrasting fragmentation and simplification of the relict landscape on the fringe of large cities are finally discussed