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The spontaneous revegetation of a disused demolition waste landfill in Rome (Italy) led to a very high vascular plant species density (269 species in 0.2 km 2 ). Vegetation was dominated by Mediterranean annual species (Therophytes), and floristic assemblage was consistent with the regional species pool. No significant levels of biotic homogenization were found. Local activists successfully campaigned to save the site from development, which resulted in its designation as an Urban Nature Reserve; however, it was essentially managed as a conventional neighbourhood park. As a consequence, vascular plant species richness decreased by 50%. The functional and biogeographic groups most typical of Mediterranean habitats saw the largest decrease (the steno-Mediterranean element decreased by 80%), leading to biotic homogenization via changes in native species only (no increases in alien species were observed). The removal of most of the old demolition-waste mounds was probably the main cause for these observed changes. These mounds provide well-drained, oligotrophic soils and micro-habitat heterogeneity. Mediterranean grassland vegetation, especially within urban areas, is often perceived as “untidy” and undesirable by local residents and decision-makers, who tend to overlook or ignore the ecological value of spontaneous grasslands—perhaps distracted by their apparently “messy” aesthetics. Mediterranean urban wastelands that are “saved” with the scope of creating public green spaces are particularly at risk of being inappropriately managed from the ecological perspective. Thus, in dry-climate regions, ecologists should be particularly careful not to dismiss the importance of aesthetic issues and cultural acceptance in urban nature conservation. Considering the results of this case-study, we offer some generalized management guidelines that can help render urban dry grasslands acceptable for recreational use, while at the same time preserving their biodiversity and educational value. [ABSTRACT FROM AUTHOR]

Fire-damaged ecosystems have often been monitored by applying a combination of field survey information and vegetation indices derived from remotely sensed data. Furthermore, it has been demonstrated that remotely sensed data can be integrated as a useful tool in predicting the recovery of fire-damaged ecosystems over time. Using regression models, the present study analyzes the trend function described by the Normalized Difference Vegetation Index (NDVI) and Fractional Vegetation Cover (FVC) 7 and 12 years after the fire. The method was performed through (i) permanent plot collection per plant community type and data reduction; (ii) comparison of the correlation established between FVC with different vegetation index contrasted with the NDVI; (iii) monitoring vegetation recovery; and (iv) a supervised classification of FVC. The NDVI was the one that correlated most with the FVC. In both the seventh and twelfth year after fire, the linear regression model was used to accurately quantify FVC based on the NDVI. Results show that 12 years after the fire, the recovery rate of the FVC associated with scrub was higher than that of the FVC of other forest classes. Although vegetation recovery is taking place, the continuing increase in the FVC associated with shrub land classes could create a state of successional stagnation. [ABSTRACT FROM AUTHOR]