F. Francesconi

Landscape changes of Rome through tree-lined roads

Rome has greatly expanded in the course of the last century, after it became the capital of the Italian state in 1870. In this period, many areas were built according to different urbanistic criteria. The city may now be divided into urban units (Wards, Districts, Suburbs and Zones), which have an almost concentric disposition. The changes of the whole urban landscape and of the single urban units (UUs) have been analysed by studying the different tree-species planted along the roads. A database has been created using the four censuses of the tree-lined roads made by the city administration in 1898, 1955, 1971 and 1998. This analysis has shown a strong link between the specific cultural and political period and the tree-species used. Moreover, for each year, the UUs have been classified according to the percentage composition of the species. The results have been mapped using the Arcview 3.1 GIS program in order to integrate them with a more general project on GIS-based cartography of the natural and anthropic vegetation of Rome.

A multiple approach for the evaluation of the spatial distribution and dynamics of a forest habitat: the case of Apennine beech forests with Taxus baccata and Ilex aquifolium

An approach integrating phytosociological and stand structure surveys with the predictive modelling of species distribution was applied to analyse the spatial distribution and dynamics of the Apennine beech forests with Taxus and Ilex, a high conservation priority forest habitat in Europe. The homogeneity of the habitat was tested trough a Mann–Whitney test between beech woods with Taxus and those with Ilex with respect to climatic, topographic, structural and environmental parameters: the former have proven to be more microthermic, mesophilous and characterised by a closer canopy. Five statistical models were compared to analyse the relationship between bioclimatic parameters and Taxus and Ilex spatial distribution: Regression Tree Analysis, the most efficient model, has shown that the distribution of Taxus is influenced by precipitation variables, while Ilex is mainly influenced by temperature variables. This model highlighted that Ilex has a potential area that surrounds, at lower altitudes, that of Taxus. A stepwise multiple regression analysis has been applied to identify the factors influencing the regeneration of the two species: beside climatic parameters, Taxus regeneration is negatively influenced by soil nitrate concentration (an indicator of livestock disturbance) while Ilex is negatively influenced by beech forest cover. Traditional management practices seem to have an effect on the regeneration of the two species: frequent cuts favour the regeneration of Ilex, reducing the forest cover and allowing more light penetration, while Taxus, less resistant to grazing livestock, is confined to more inaccessible places. The multiple approach has proven to be useful for the elaboration of two differentiated conservation strategies for the two beech forest types.

Classifying and Mapping Potential Distribution of Forest Types Using a Finite Mixture Model

The present paper presents the application of a finite mixture model (FMM) to analyze spatially explicit data on forest composition and environmental variables to produce a high-resolution map of their current potential distribution. FMM provides a convenient yet formal setting for model-based clustering. Within this framework, forest data are assumed to come from an underlying FMM, where each mixture component corresponds to a cluster and each cluster is characterized by a different composition of tree species. An important extension of this model is based on including a set of covariates to predict class membership. These covariates can be climatic and topographical parameters as well as geographical coordinates and the class membership of neighbouring plots. FMM was applied to a national forest inventory of Italy consisting of 6,714 plots with a measure of abundance for 27 tree species. In this way, a map of potential forest types was produced. The limitations and usefulness of the proposed modelling approach were analyzed and discussed, comparing the results with an independently derived expert map.

Sharing Italian Botanic Gardens’ living collections: The role of the National Biodiversity Network

Abstract This paper presents the role of the Italian National Biodiversity Network in making available biodiversity data from Italian Botanic Gardens at a national and international level. The case study of the Botanic Garden of Rome is presented explaining procedures and methods for collecting georeferenced data on living plant species and making them available through web-based applications.

MULTIFUNCTIONAL ANO MULTIMEDIA GIS SYSTEM FOR THE INVENTORY ANO THE MANAGEMENT OF THE WETLANOS OF PUGLIA REGION (SOUTHERN ITALY)

The Puglia region is characterised by an homogeneous calcareous basement, affected by karst processes. so as to have a noticeable water reservoir. lts wetlands are the result of the complex interaction or geo-hydrological. climatic and biogeographical factors. The conservation of these remnant wetlands is menaced by human activity: land reclamation, pumping of water table, loading of pollutants, tourism and poaching. In order to conserve these habitats a two phases project was carried out. In the first phase the wetlands were identified and mapped in a GIS system. In this way 36 wetlands were mapped. These areas were grouped into the following categories: ponds and marshes (15). artificial basins and saltpans (6). meanders (5), lakes (3), swamps (3),estuaries (2). lagoon (I). gulf (I). A description has been hot linked to each area: physical and biological characteristics, previous land uses, environmental perturbations; level of protection; restoration activities to be undertaken. In the second phase three sample areas were chosen to develop a method for their characterisation. The areas are: l-Torre Guaceto, a brackish marsh bounded by sand-banks, 2-Frattarolo swamp, a salt swamp characterised by grasslands mainly composed by halophytes. 3-Lago Salso, an artificial al basin created for agricultural and hunting purposes, characterised by a mosaic of vegetation, mainly composed of hydrophytes and hygrophilous species, and of sheets of water, which represent an idoneous nesting and roosting area for many bird species, A spatio-temporal GIS database was developed using 19 digital orthophotos in order to analyse the changes that have occurred in the last fifthy years. Then the efficiency of a quantitative evaluation index was verified, This index was calculated using a GIS extension named Wetlands Rapid Assessment Procedure (WRAP). This procedure is based on the ranking of the ecological factors chosen for the evaluation: wildlife. vegetation, buffer area, hydrology and water quality. Multimedia information such as graphics. tables. ground photographs and digital video was used to highlight the more interesting characteristics of those wetlands and the GIS systems was modified to develop a more suitable user-interface for an easy access to both the spatial dataset and the multimedia information.