Spatial Monitor Flanders: Managing spatial data in support of policy making

Transcription

1 EnviroInfo 2011: Innovations in Sharing Environmental Observations and Information Spatial Monitor Flanders: Managing spatial data in support of policy making Bjorn Debecker 1, Thérèse Steenberghen, Paul Jaxcsens Abstract The Spatial Monitor Flanders (Ruimtemonitor Vlaanderen) is a digital GIS tool to support policy making in the field of spatial planning in Flanders, based on spatial indicators developed by researchers under the umbrella of Flanders Policy Research Centre of Spatial Planning and Housing. Different research domains provide environmental quality indicators such as e.g. concentration of gardens, forest fragmentation, renewable energy indicators, and indicators that impact the environment (e.g. car density, urban sprawl, housing density, ). The Spatial Monitor provides a direct and user-friendly access to these indicators and their calculation tools, through a dual approach. Via the web portal maps of all indicators can be viewed and limited access to the data is provided. The web portal is entirely constructed with Free and Open Source software (GeoServer, GeoNetwork, PostgreSQL). For more advanced analyses, a second version of the Spatial monitor is developed as an extension to ArcGIS 9.3/10 (ESRI ). This tool allows the experienced GIS user not only to consult, but also to analyse and to edit or to construct indicators. Additionally, in ArcGIS ModelBuilder, the calculation processes of indicators are entirely documented and automated to simplify consistent and correct modifications or updates. As the two applications serve different tasks and partially different user groups, they are complementary. An important technical issue is the synchronization of data between the web portal and the desktop application. Bridging the gap between Open Source software and proprietary software is maintained by the systems administrator by means of several software tools. Data management of the indicators consists of: development of the management tools, collecting & archiving the indicators, publication and finally maintenance (standardization, updates, synchronizing, data checks, ). The main drive behind the Spatial Monitor is the initiation, the promotion and the support of an interactive user community (consisting of key players in the dialogue between government and public community in the field of spatial planning) where indicators are developed, applied, updated, discussed and shared. 1. Introduction Nowadays, a large amount of spatial data is available on environmental topics, as well as on other domains of spatial planning. In order to support policy making, these data need to be organised and presented in an understandable and concise manner. This can be accomplished by converting the data into clear and straightforward indicators. For an efficient use, these indicators have to be easily accessible and shared. In addition, they should be well maintained, documented, harmonized and updated. Different authors have expressed the importance of providing indicators at a regional (or smaller) scale, rather than just generating numbers and graphs on a national level. For example (Fjellstadt 2010) conclude 1 K.U.Leuven, Spatial Applications Division Leuven, Celestijnenlaan 200E, B-3001 Leuven bjorn.debecker@sadl.kuleuven.be, Internet:

2 in their study on agri-environmental indicators in Norway that analysis of disaggregated data from indicator programs can lead to important insights, in support of national policy development. The Spatial Monitor aims to facilitate a multi-level, integrating framework by collecting, distributing and maintaining the most relevant spatial indicator data available in this area. 1.1 Spatial Indicators on environmental issues In the Policy Research Centre of Spatial Planning and Housing ( ) research on sustainable spatial planning is performed by researchers in Flemish universities and research institutes, in support of the Flemish Department of Town and Country Planning, Housing Policy and Immovable Heritage (RWO). The Research Centre generates a variety of output on relevant spatial topics such as future scenarios, prospective design, review of policy instruments,... The majority of work packages start with an analysis of past and present spatial processes in various domains such as urbanisation, mobility, housing,.. Next to scientific reports, these studies also result in the development of spatial indicators. These indicators form the contents of the Spatial Monitor Flanders. Throughout the different domains involved, there is an important consideration for environmental topics. This is reflected in two ways. First, there are the indicators that express a direct measurement of environmental features: concentration of gardens (Dewaelheyns/Bomans/Gulinck 2008), forest fragmentation (Figure 1), number of horses per municipality (Bomans/Dewaelheyns/Gulinck 2011),.... In this category one can also find maps in the Spatial Monitor that present renewable energy installations in Flanders and the potential energy production expansion areas (based on a study by (Lastra Bravo 2011)). Figure 1 Indicator for forest fragmentation in Flanders, as part of the Spatial Monitor Flanders, ranging from a very low degree of fragmentation (light green) to a very high degree (dark green) Source: Kirsten Bomans, KULeuven, based on AGIV data The Spatial Monitor also includes several indicators that have an (in)direct impact on the environment. Following the study by (Verbeek 2010), the same authors generated indicators on housing and open space density, where it can be seen that the boundary between the Flemish urban and rural areas faded in recent years and a fragmented spatial structure emerged (Figure 2). They suggest the control of accessibility of

3 the countryside as a means to guide this evolution, considering the limited carrying-capacity of open space. The gradual fading of this urban-rural boundary is the consequence of urban sprawl. (Pisman 2009) found that for the city of Ghent (B) residential neighborhoods with a higher status are situated in specific urban sprawl areas, rather than in more rural areas (Figure 3). Another example is the study of (Boussauw/Witlox 2009) on the relationship between energy consumption, daily travel distance and spatial characteristics in Flanders. They calculated that residential density and land use mix in urban areas is the best guarantee for curbing excessive mobility (and consequently environmental impact). Their indicators on car density can be found in the Spatial Monitor (Figure 4). (Bomans 2010) state that the current categorizations of land use and land cover are not always able to catch transformations related to competition for space. They call for the development of integrated maps, based on an expanded information basis, depicting at appropriate scales the spatial diversification and combinations of functions, values and patterns in open space. Also (Bock 2005) argues for an integrated approach of multiple applications and ways of modeling for the development of spatial indicators for nature conservation. Figure 2 Indicator for the degree of built area in Flanders (in percentage), as part of the Spatial Monitor Flanders. The areas with the smallest degree of built area have become scattered Source: Thomas Verbeek, UGent, based on AGIV data

4 Figure 3 Different housing environments in the south of the city of Ghent (B). High end residential neighborhoods (red colors) are situated in urban sprawl areas, rather than in a rural environment Source: Ann Pisman, UGent Figure 4 Daily energy consumption per capita for travel between home and workplace Source: Kobe Boussauw, UGent, based on data from the Social Economical Survey 2001 & MIRA

5 1.2 The Spatial Monitor as a management instrument for indicators The discussion above demonstrates the need for a qualitative instrument to manage spatial indicators. The Spatial Monitor Flanders is developed to meet this demand. The technical specifications are discussed in the next chapter, but first it is explained what the term indicator management encompasses in the context of the Spatial Monitor. The indicators are collected from the different research groups in the Research Centre, and prepared for admission in the Spatial Monitor. Most indicators are delivered as, or converted into GIS-layers. Subsequently, the various indicators are harmonized concerning lay-out, map elements and metadata. Researchers and policy makers involved need an easy access to the contents of the Spatial Monitor. On the other hand, given the sometimes confidential nature of the data, the user access is restricted and on demand for people outside the Research Centre. The fourth and most extensive task is maintenance and support in the Spatial Monitor. Whenever new source data is available, it should be checked if indicators can be updated. Similarly, contact data on indicators has to be well-maintained (address changes, personal replacements, ). In addition, it is verified regularly if all data in the Spatial Monitor are synchronized. A forum is developed which not only serves for mutual support between users, but also as archive of all relevant correspondence concerning Q&A on indicator data, indicator calculation methods and technical specifications of the GIS instruments. 2. Software Architecture 2.1 A dual approach When considering the application of spatial indicators, the subdivision can be made between users who consult indicators and users who produce, analyse and edit indicators. In order to optimally meet the demands of the different tasks and both user groups, the Spatial Monitor Flanders is constructed as a dual GIS-instrument. A first form is the web portal, more specifically a geoportal, where maps can be viewed and consulted via an ordinary browser. This provides a quick and easy acces, without any specific requirements for software or GIS skills. Secondly, a similar interface is developed as an extension for ArcGIS. Through this desktop application, the user can transfer any indicator layer into the ArcGIS environment, where advanced analyses options are available. Obviously, this requires a certain understanding of GIS software from the user. In the next part, both applications are discussed more in detail, regarding functionality and applied technology. While the web portal is based on Open Source Software, the desktop application operates in a proprietary software environment. A last paragraph will deal with the harmonisation between both applications. 2.2 The web portal For new users, the web portal is usually the first acquaintance with the Spatial Monitor Flanders. It can be accessed from anywhere, with any recent web browser via the address However, apart from the welcome screen, access is moderated and only possible after approval of registration. The user policies are discussed more in detail in the last part of this paper. Since this web portal is currently exclusively developed for Flemish policy makers & researchers, the language on the interface is Dutch. Upon access, the user can chose to consult the different indicators, that are grouped according to the work packages within the Research Centre (namely economy, urbanisation, open space & agriculture, mobility & infrastructure, tourism and housing (Figure 5). Alternatively, one can search for a specific indica-

6 tor by means of search terms. For each indicator one can view metadata (description of the indicator, author contact data, reference to source data, ) and a graphical presentation of the indicator. For most indicators, the latter consists of a map of Flanders where the indicator is presented per relevant geographical unit (i.e. km-cel, statistical sector or community). Figure 5 Overview screen of the web portal (with Dutch interface). Icons for the different indicator groups on the left, list of indicators on the right together with buttons to view, edit and add metadata, and to view maps. In addition, for some cases, the indicator is also available as a time series, i.e. a chronological series of maps where the indicator is presented for each given year. This can be in the form of an animated movie or by means of a split screen where the user can compare an indicator between two different years (Figure 6). The web portal is entirely based on Free and Open Source Software (FOSS). The main components are GeoServer, GeoNetwork and PostgreSQL. GeoServer is an open source software server written in Java that allows users to share and edit geospatial data. It is the reference implementation of the Open Geospatial Consortium (OGC) Web Feature Service (WFS) and Web Coverage Service (WCS) standards, as well as a high performance certified compliant Web Map Service (WMS) (GeoServer 2011). In other words, GeoServer provides the means to make geographical data available online. To actually show this geographical data, GeoServer applies the Open Layers web mapping library. Of course, the data to be shown has to be stored on a server. In the Spatial Monitor web portal, the data is stored on a PostgreSQL database. An extension to this database server, namely PostGIS allows for the storage of the geographical component of the data. The last essential part for the web portal is a cataloging application for the spatially referenced data. GeoNetwork, another open source project, provides this service. By implementation of its Catalog Service (CSW), common browser interfaces and metadata queries are available (Ozana/Horakova 2008). The metadata itself, in addition to the geographical data, is also stored on the PostgreSQL database.

7 Figure 6 Time series for greenhouse culture in Flanders, presented by a split screen in the Spatial Monitor Flanders, ranging from high (yellow) to low (dark brown). The upper screen shows the data for the year 1990, the lower screen for 2005 Source: Kirsten Bomans, KULeuven based on data from the National Institute for Statistics Worldwide, several interesting projects have been set up with (parts of) the prementioned software in the field of environmental sciences. With the open source character of the software, a worldwide community of users is developing, whose voluntary contributions continuously help to improve it. An interesting example of the application of GeoServer is by (Schrader-Patton/Ager/Bunzel 2010) who developed a Geobrowser to explore Wildland Environmental Threats (insects and disease, fire hazard, etc) for the USDA Forest Service. Other examples are (Olivé 2009) who integrated GeoServer for real time monitoring of oceanographic data on board research vessels, or (Schotman 2009) who applied GeoServer in their spatial evaluation of meadow bird habitats. 2.3 Desktop application The desktop application of the Spatial Monitor is developed in C#.NET as an extension within ArcGIS 9.3 or ArcGIS 10. Consequently, the use of the desktop application requires the presence of ArcGIS on the user s computer. Contrary to the web application, the desktop application needs to be installed on each computer where it is to be used. The applied indicator data though can be installed centrally on a server. Indicator data is stored as shapefiles and layer files on a server. The Spatial Monitor extension provides a browser window, similar to that in the web portal, only here one has the functionality to add the layers directly into the ArcGIS application. This gives the user the possibility to edit and/or process the data with all the functions available in ArcGIS. Another application of the Spatial Monitor in ArcGIS is the use of Modelbuilder to automate indicator calculation processes. This is discussed more in detailed further on in this text.

8 3. Harmonisation between Open Source software and proprietary software The choice to combine Open Source software with proprietary software proved to be challenging in several aspects. Although the Open Source software in this project was free of charge, it demands a considerable investment in personnel hours in order to study, to set-up and to maintain the software. Naturally, the experience gained in this area will be used in future projects. The main issue is the interoperability of different geospatial file types. Initially data are created and stored as shapefiles and layer files in ArcGIS for the desktop application. But, although shapefiles are supported in GeoServer, it is recommended to rather use databases such as PostgreSQL (with PostGIS extension), which are more suitable in production and offer better performance and scalability (website GeoServer). Thus, it would be a more obvious choice to store the data for the two applications on one common PostgreSQL database. However, in ArcGIS 9.3 PostgreSQL is not supported without an extra interoperability extension (which does not come standard). It would be against the philosophy of the project that the integration of Open Source software on the one side would lead to extra costs on the proprietary software on the other side. Thus, it was opted to store the data twice, once as shapefiles for the desktop application, and once as PostgreSQL records for the webportal. The translation from shapefiles to PostgreSQL records is perfomed by shp2pgsql, a freeware tool. Since this program does not automatically run when any changes are made, one must be careful to keep both datasets synchronized. After all, the contents of both Spatial Monitor applications (attribute data and geographical coordinates) should be at all times identical, only the form varies (shapefiles versus PostgreSQL records). Note that in the new version of ArcGIS (v10), support for PostgreSQL comes now standard, so in the future we might switch to one central PostgreSQL database for both applications of the Spatial Monitor. The second, and larger obstacle in this area, is the lay-out. In ArcGIS, lay-out is stored as layer files. However, this format is protected from use by other software. GeoServer supports the alternative SLD (Styled Layer Description) format. Thus another conversion has to be performed, this time for the lay-out files. Here there are two options. First one can open the shapefile in an Open Source GIS program like UDIG which supports SLD. Thus, the lay-out can be completely recreated manually and the SLD is exported for use in GeoServer. This can be a tedious work. Alternatively, recent tests with Arc2Earth, a third party software that runs as an extension in ArcGIS allows to export the layout in ArcGIS directly in the SLD format. Arc2Earth is also proprietary software, but there is a free light version available that fully supports the SLD export functionality. This drastically improves the lay out interoperability. However, as Figure 7 Technical specifications of the two applications of the Spatial Monitor, with indication of their internal links

9 long as ESRI, the producer of ArcGIS does not support other lay out formats like SLD, or opens up its own layer format, it will not be possible to use one lay-out file that can be used by both applications of the Spatial Monitor. Figure 7 gives an overview of the most important technical components of both application of the Spatial Monitor. In addition, it is indicated how both applications are linked: 1) use of a common PostgreSQL database for metadata, 2) data format transformation with shape2pgsql and 3) lay out format transformation through manual scripting in UDIG, or alternatively with Arc2Earth. 4. Managing Indicator Calculations In the desktop application, the use of ModelBuilder tools is encouraged. With the ModelBuilder extension in ArcGIS, the calculation process of any indicator, i.e. its succesive series of GIS operations, can be automated. ModelBuilder is a part of the geoprocessing framework of ArcGIS and can run any tool in the ArcGIS toolbox, including scripts, custom tools and other models (Armstrong 2011). Figure 8 shows the schematized workflow of the indicator model for forest fragmentation. The largest advantage of the ModelBuilder application is that a calculation process is exactly and completely archived, and documented. Contrary, when only a written description of a calculation process is available, there is always a considerable chance that some parameters are missing in order to repeat the exact calculations. Furthermore, an indicator can be very easily updated when updated source data are entered in the indicator model. The indicator models are also well suited for sensitivity analyses. By parameterising a certain parameter, one can recalculate the indicator for different values of this parameter, in a structured and fast manner. Some examples of such a sensitive analysis can be: the influence of a buffer distance around a forest patch, the influence of working with minimum, maximum or average values when calculating population density per community,. Finally, any new indicator model can be applied as any other ArcGIS tool, in a closed form with limited degrees of input freedom. It is the developer of the tool that can decide which layers and input values are parameterized, i.e. can be chosen freely when the model is run. In this way, the models can be used by ArcGIS users that are inexperienced with ModelBuilder. Figure 8 ModelBuilder model in ArcGIS for the calculation of the indicator Forest Fragmentation. Bleu ellipses represent input data, green ellipses output data and yellow rectangles represent spatial ArcGIS operations

10 The models in the Spatial monitor exist in two versions. First there is a demo version that works with small data sets, and consequently short calculation times. These demo versions are useful to study an indicator in a partial study area, or to present a quick demo. It is however a complete tool with complete functionality. Second, there is the full version for complete data sets with calculation times that can take up to several hours. These models sometimes require modified operations for large data handling (i.e. splitting and merging datasets). Currently 10 models are included in the Spatial Monitor s desktop application, each in demo version and full version. They serve as an incentive for further development of new models. Ideally, in the future, each indicator should be provided with its own model. 5. Towards an interactive user-community The Spatial Monitor Flanders project aims to initiate and to promote an interactive user community where indicators are developed, applied, updated, documented, discussed and shared. The initial user group of the Spatial Monitor consists of civil servants of the Flemish spatial planning department, as well as the researchers within the Research Centre. At this time, also the Research Centre of the Flemish Government and the provincial spatial planning departments are integrated in the user group. Although the user group is limited, it consists of key players in the dialogue between government and public community in the field of spatial planning. Figure 9 gives a schematic overview of the different users and interactions in the Spatial Monitor project. To support the user community, a forum is used for sharing and archiving discussions among and across researchers and civil servants. The forum is open for discussion related to contents (i.e. indicator data, source data, calculation methods, ) as well as for questions about applied software. This leads to a flexible and self-learning system: the more users, the more new spatial transformations, indicators, possible calculations and data sources can be identified and developed. A critical note is raised here. The Spatial Monitor can only exist with the presence of a sufficiently large and participative user community. Since it is a new instrument, it requires significant effort to introduce the Spatial Monitor on the work floor. Therefore, its promotion is a very important task at this stage. Without enough active users, the risk exists that data is not updated, evaluated or applied. Such a status quo is not an option for this project. In this regard, one can neither underestimate the importance of software maintenance. As the underlying technologies and services rapidly evolve, new versions of the Spatial Monitor appear. Developing, maintaining and installing the software is thus another key task in support of the user community. It will be interesting to see how the indicators evolve as the user group evolves. Different users have different needs and different opinions on quality of indicator data. (Devillers 2007) state correctly that not all users evaluate quality based on the same criteria. For instance, certain users will be more interested in spatial accuracy, others in completeness, some in temporal data quality, and so on. Quality and suitability of indicators is a continuous point of interest. The work from (Devillers 2007) on combining concepts from GIS and Business Intelligence to support expert users in the assessment of the fitness for use of a given dataset, can be a valuable inspiration.

11 Figure 9 Schematic overview of the users groups & their mutual interaction around the Spatial Monitor 6. Conclusion In this project, four distinct achievements were realized. First, in the Spatial Monitor Flanders spatial indicators and their calculation methods are stored, documented and harmonized. The indicators collected are in support of spatial planning and both direct and indirect environmental indicators are included. Second, the two application provide for two different types of use. The easily accessible web portal decreases the threshold for new users, while the desktop application offers the extended ArcGIS spatial analysis functionalities for the indicator data. Third, the challenge to synchronize data within an Open Source environment to data within a proprietary software environment is successfully tackled. It is also noted that software developments on both sides evolve fast and allow for new, improved possibilities of interoperability. On the other hand, the constant changes in software requires permanent maintenance of the tools. Fourth, the Spatial Monitor provides the means for an interactive user community where spatial data and indicators are always in progress. Users do not just consult data, but also contribute by delivering new indicators or by helping to adjust existing data through discussions and comments. The forum support this creative process. Thus, a versatile, interactive and easy to use GIS instrument is implemented to support policy making. Acknowledgements This project is commissioned by Flemish Department of Town and Country Planning, Housing Policy and Immovable Heritage.

12 Bibliography Armstrong, K. (2009): ModelBuilder: An Introduction, Esri Southeast Regional User Group Conference, Held in Jacksonville (USA). Bock, M. (et al.) (2005): Spatial Indicators for Nature Conservation from European to Local Scale, in: Ecological Indicators, 5, pp Bomans, K., Dewaelheyns, V., Gulinck, H. (2011): Pasture for Horses: An Underestimated Land Use Class in an Urbanized and Multifunctional Area, in: Journal of Sustainable Development and Planning, 6(2), Article in Press. Bomans, K. (et al.) (2010): Underrated Transformations in The Open Space The Case of an Urbanized and Multifunctional Area, in: Landscape and Urban Planning, 94, pp Boussauw, K., Witlox, F. (2010): Travel Energy Consumption and the Built Environment : Evidence from Flanders, Proceedings of Conférence Permanente du Développement Territorial (CPDT), Held in Liège (B), pp Devillers, R. (et al.) (2007): Towards Spatial Data Quality Information Analysis Tools for Experts Assessing the Fitness for Use of Spatial Data, in: International Journal of Geographical Information Science, 21(3), pp Dewaelheyns, V., Bomans, K., Gulinck, H. (2008): Dispersion, Spatial Associatons and Morphology of Gardens in Flanders (in Dutch), Ad hoc assignement Policy Research Centre Space and Housing. Fjellstad, W., Puschmann, O., Stokstad, G. (2010): Addressing the Spatial Resolution of Agri- Environmental Indicators in Norway, Proceedings of the OECD Workshop on Agri-Environmental Indicators, Held in Leysin (CH). GeoServer (2011): GeoServer website, (Date of acces: May 2011). Lastra Bravo, X. (et al.) (2011): Renewable Energy in Flanders. Current Situation, trends and potential related to spatial planning, Proceedings of the World Renewable Energy Congress, Held in Linköping (S), p. SCR0642. Olivé, J. (et al.) (2009): Geographic information system architecture applied to oceanographic data acquisition systems, in :Instrumentation Viewpoint, 8, pp Ozana, R., Horakova, B. (2008): Actual State in Developing GeoNetwork Opensource and Metadata Network Standardization, Proceedings of the Sborník sympozia GIS, Held in Ostrava (CZ). Pisman, A., Verbeek, T., Allaert, G. (2009): Lifestyles and Patterns of Housing Environments in Periurban Areas in Flanders, Proceedings of the SCUPAD Congress :!Lifestyle? versus Life Patterns : Planning for New Urban and Rural Interdependence, Held in Salzburg (AU). Schotman, A. (et al.) (2009): An Internet-Accessible Knowledge System on Spatial Evaluation of the Habitat of Meadow Birds, Proceedings of the 18th World IMACS / MODSIM Congress, Held in Cairns (AUS), pp Schrader-Patton, C., Ager, A., Bunzel, K. (2010): GeoBrowser Deployment in the USDA Forest Service: A Case Study, Proceedings of the 1st International Conference and Exhibition on Computing for Geospatial Research & Application, Held in Bethesda (USA). Verbeek, T. (et al.). (2010): Public and Private Use of Open Space in a Densely Urbanized Context, Proceedings of the 24th AESOP Annual Conference, held in Aalto (FIN), pp