## 3 Quantification, Assessment, and 3D Visualisation of UES in Naples
### Classification of UES
Regulation functions maintain a \"healthy\" ecosystem at different scale levels and provide the necessary pre-conditions for all other functions. * _Carrier_, including a group of functions related to different human activities (e.g., cultivation, habitation, and transportation) that require space and a suitable substrate (soil) or medium (water or air) to support the associated infrastructure, involving the permanent conversion of the original ecosystem. * _Information_, selecting essential \"reference functions\" that contribute to the maintenance of human health by providing opportunities for reflection, spiritual enrichment, cognitive development, recreation, and aesthetic experience. Assuming the classification of functions suggested by [PERSON] [87], Table 1 shows the selection of indicators in six levels, identifying three functions of UES, the tier as the specification of the function, the units of measure, the type of geometric entity, the distance threshold (DT) in metres, and the data sources. The geographical data were processed using multi-criteria procedures to provide indicators as proxies for UES status detection. The following list specifically explains each tier of the database that was gathered for the focus area, amounting to 21 tiers of geographical data with physical information. Within the category of Regulation functions, the followings five tiers were processed:  
* _Environmental protection area_ includes the surface per cell of Italian communitarian interest sites (SIC) and special protection zones (ZPS). These areas provide a relevant contribution to the maintenance/conservation of regulation services. * _Waterbody_ shows the surface per cell of the sea, lakes, fish ponds (natural or artificial), and rivers. For specific locations, this indicator is a disservice, as the quality of water in proximity to urban centres is frequently compromised by pollution. Nevertheless, this contribution does not provide detailed data about this phenomenon. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Urban Ecosystem** & **Tier** & **Unit of Measure** & **Geometric Entity** &
\begin{tabular}{c} **Distance** \\ **Threshold (DT)** \\ \end{tabular} & **Source** \\ \hline Regulation & Environmental protection area & Sq. km & Polygon & 2500 & Natura 2000—EC \\  & Waterbody & Sq. km & Polygon & 300 & Urban Atlas—EEA \\  & Forest & Sq. km & Polygon & 2500 & Urban Atlas—EEA \\  & Land without current use & Sq. km & Polygon & 100 & Urban Atlas—EEA \\  & Waterway & Km & Line & 300 & OpenStreetMap \\ Carrier & Railway & Km & Line & 100 & OpenStreetMap \\  & Road & Km & Line & 100 & OpenStreetMap \\  & Airport & Sq. km & Polygon & 1000 & Urban Atlas—EEA \\  & Port & Sq. km & Polygon & 1000 & Urban Atlas—EEA \\  & Bus/underground stop & Number & Point & 500 & OpenStreetMap \\  & Mineral extraction site & Sq. km & Polygon & 100 & OpenStreetMap \\  & Habilations & Buildings & Polygon & 100 & Urban Atlas—EEA \\  & Pers sq. km & Polygon & 100 & OpenStreetMap \\  & Waste disposal & Sq. km & Polygon & 100 & OpenStreetMap \\  & Tourism facility & Number & Point & 500 & OpenStreetMap \\ Information & Cultural site & Number & Point & 2000 & OpenStreetMap \\  & Place of worship & Number & Point & 500 & OpenStreetMap \\  & Sport and leisure & Sq. km & Polygon & 500 & Urban Atlas—EEA \\  & Green urban area & Sq. km & Polygon & 1000 & Urban Atlas—EEA \\  & Attraction place & Number & Point & 500 & OpenStreetMap \\  & Attractive landscape feature & Number & Point & 1000 & Panoramio/Flickr \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Urban Ecosystem Service indicators. * _Forest_ includes both protected and non-protected areas that provide a positive contribution to urban ecosystems in terms of biological exchanges, air quality, raw materials, and green footprints. * _Land without current use_ refers to the abandoned areas that, if correctly managed, can improve the regulation service maintenance/conservation.