**Author details**

18 Current Air Quality Issues

which are certified by shared *standards*.

**Leverano**

ICK" and "Prediction map of ICK" layers.

**6. Conclusions**

**Copertino**

This function has been used to query the database associated with the layer "Permeability" and visualize, by using the thematic map, the study area with high level of permeability overlapped to the layers "level curves of ICK" and "Prediction map of ICK". In this case, the user can identify areas of high level of permeability close to area with high Rn concentrations. Interactive navigation of maps is possible by using the tools implemented in the RnWebGIS,

On the other hand, in order to ensure the interoperability (i.e. exchange and/or sharing) of geographic data, it has been relevant to build a RnWebGIS according to the specifications of the services, defined by the *Open Geospatial Consortium* (OGC). Indeed, by using the features implemented in the RnWebGIS, the user can also integrate data located on different servers as well as data of different formats. This is possible by recalling the WMS given by the OGC that avoids duplication of data and, at the same time, provides updated geographical data

For example, it is worth highlighting that, by using the appropriate WMS, an orthophoto of Lecce district can be integrated with the layer "Prection map of OCK " as shown in Fig. 13.

> **San Donato di Lecce**

level curves of ICK Rn concentration Prediction map with ICK

> /m3 kBq /m3 kBq /m3 kBq /m3 kBq /m3 kBq /m3 kBq /m3 kBq kBq/m3 /m3 kBq /m3 kBq /m3 kBq /m3 kBq

5.18 - 10.31 10.31 - 15.43 15.43 - 20.56 20.56 - 25.56 25.69 - 30.82 30.82 - 35.94 35.94 - 41.07 41.07 - 46.20 46.20 - 51.32 51.32 - 56.45

0.05 - 5.18

Satellite picture 2006 **WMS**

56.45 - 61.58

such as the use of *zooming/panning* available by selecting the object on the map.

**Arnesano**

**Nardò Galatina**

**Figure 13.** Orthophoto of Lecce district, obtained by the WMS and integrated with the "Rn sites", "level curves of

In this paper, after introducing the usefulness of a GIS supported by geostatistical results, and reviewing some geostatistical modeling and predictions techniques used in the univariate and multivariate cases, a case study concerning a thorough geostatistical analysis of the Rn concentrations in soil gas over Lecce district has been discussed. In particular, four different spatial interpolation techniques, that is Ordinary Kriging, Log-normal Kriging, Cokriging with Indicator variable and Kriging with Varying Local Means, have been used in order to predict the Rn concentration levels over the study area. Then, an *ad hoc* WebGIS, called RnWebGIS, has been proposed. The map of the Rn predictions obtained by using Cokriging with Indicator variable, which performed more accurate predictions than the ones obtained by using the other methods, has been stored into the WebGIS, together with several Veronica Distefano, Sandra De Iaco∗, Monica Palma, Donato Posa, Alessandra Spennato

\*Adress all corresspodence to: s.deiaco@economia.unile.it

University of Salento, Department of Management, Economics, Mathematics and Statistics, Italy

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**Chapter 19**
