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GIS in Environmental Decision Making Development of Environmental Applications with
MapObjects Marco
PAINHO1, Ricardo SENA2 e Pedro CABRAL3 New
Technologies Laboratory Instituto
Superior de Estatística e Gestão de Informação New
University of Lisbon Trav.
Estêvão Pinto – 1070-124 LISBOA – PORTUGAL Telefone:+351-21-3870413;
Fax:+351-21-3872140 emails:
1painho@isegi.unl.pt, 2rsena@isegi.unl.pt and 3pcabral@isegi.unl.pt Abstract The Environmental Impact
Study System and the Environmental Adjustment Contracts Monitoring System from
the Environmental General Directorate, and the Constraints Evaluation System
from the Environmental Regional Directorate of Alentejo, both from Portugal,
are applications that were developed to perform specific tasks that include
environmental information. The main purpose is to provide easy-to-use tools
that makes possible the integration, storage, edition and analysis of
environmental information, helping the environmental technicians to support
their decisions. This paper describes the methodology and the functionalities
of this three applications developed using MapObjects, at the New Technologies
Laboratory of ISEGI - New University of Lisbon. 1. Introduction Environmental
decision-making is a complex task that demands a great amount of information.
All the data that is used by these type of systems needs to be correctly
integrated in the organization in order to be used, maintained, processed,
stored and analysed. Environmental data is Earth-related data and GIS provides
the most effective tools to tranform these data into useful information. With the recent developments
in GIS technology it is now possible to develop GIS user-oriented applications
that are fully integrated with the other information systems that operate
within the organization. GIS applications are becoming based in standard
technologies, leaving aside their proprietary developing and customizing
environment. Many spatial databases are now available for analysis but the
available GIS software is still far from being usable for most of the users.
There are insufficient analysis tools that allow all the users to perform
effective spatial analysis, without GIS software specialists help. These advances in software
development made possible to build up specific, easy-to-use, tailored GIS
applications with component software. Using component object model (COM)
architecture, it is possible to develop independent pieces of software
(components) that can be incorporated into other applications. This is a
powerful feature that makes possible the reduction of the resources spent on
the development of more applications. Component software, like MapObjects from
ESRI, allows the use of standard development environments like VB, Delphi or VC
++, to develop applications that integrate GIS functionalities. It works like a
set of new objects, in this case mapping objects, that can be attached to these
development programs and programmed. It is also possible to customize and
extend existing software packages to better fit user needs using this
programming languages. The environmental agencies
who we are working with are a good example of users who do not not have the
right tools to perform an effective spatial analysis. They have the heavy GIS
software, terabytes of spatial databases but, they lack of easy-to-use,
tailored applications that everybody knows how to use. Everytime it is
necessary to perform a spatial analysis there is the need to to spend several
hours with their GIS specialist. These are the reasons why we have choosed to
implement these kind of solution: we want to make tools that everybody can
actually use. This is not a solution for the experts but for all the
technicians that are not GIS experts. With these interfaces we are only
interested in providing the functionalities needed to perform specific tasks.
One of the advantages of these kind of software is the possibility of easily implementing
new functionalities if there is the need of doing that in the future. 2. DEVELOPMENT PROCESS The development of these
applications was based in a methodology that integrated all the phases of the
implementation process. This methodology had to be flexible enough to make
possible the introduction of new features at any time of the developing
process. The adoption of a
development model allowed, among other features, to:
The development model
adopted to develop these applications is based on Barry Bohem’s Spiral model
(Figure 1). This is an incremental and iteractive model that incorporates a
risk analysis into the process and allows the developers to stop the process
depending on the expected results from new requirements that are incorporated.
Figure
1 Barry Boehm’s Spiral Model (adapted) On the first turn of the
spiral model the objectives are defined and the constraints and alternatives
are identified. After analysing all this information the application
development is started resulting in the first prototype. This first prototype
will not be for sure one that satisfies all the requests of the project but it
will have to be analysed and evaluated by the users in order to make the
necessary changes. With the feedback provided by the users, there will be a new
iteration on the spiral that will result in a new prototype. These iterations
will only finish when a satisfactory prototype is achieved. To implement this
type of iteractive development we used a rapid application development (RAD)
tool - Visual Basic - in order to reduce the turns we had to make to the
spiral. 3. IMPLEMENTATION PROCESS The development model and
its implementation were based on a technology that allowed the development of
spatial enabled applications: the ESRI programmable mapping components -
MapObjects. These mapping components can be integrated in any standard
development environment. We adopted Visual Basic, mainly its database
capabilities and because it is a RAD tool, which enabled the reduction of the
development life cycle. The implementation based in
objects and components has several advantages, namely:
By using this type of
implementation the system was structured in a set of related objects that
provided a set of features. The identification and definition of the several
objects were made on the phases of the analysis and design of the system. In
the implementation phase, these objects were organised and structured in
components. Each of these independent components took care of a specific domain
of the program. For example, there is a component, with several objects, that
has the responsibility of accessing and retrieving data from the database, or
other, that only has objects about functionalities related to the interface. The definition of the object
model is crucial for achieving successfuly the objectives of the system that is
being developed and also to make possible the re-use of the components in
future application development. This way it is possible to develop independent
pieces of software (components) that can be incorporated into other
applications. This is a powerful feature that makes possible to reduce the
resources spent on the development of more applications.
Figure
2 – Three-Tier architecture The structure and
organization of these objects/components is done using the three-tier
architecture (Figure 2). This architecture makes a logical separation of the
system in three different levels each one representing a set of services. 4. APPLICATIONS 4.1 Environmental impact
studies evaluation support system According to the Portuguese
law, corresponding to the transcription of the European directive nº85/337/CEE
of 27th of June, for the construction projects that may have an impact on the
environment it is necessary the elaboration of a study to determine and
describe those impacts. The elaboration of the Environmental Impact Studies
(EIS) needs to be made by the promoters of the construction projects.
Basically, the EIS identifies the most important environmental impacts, the
actions to reduce or avoid them and the alternatives for the implementation of
the construction project. The EIS makes comparative analysis of the several
alternatives for the project. The Environmental General Directorate (DGA) is
the governmental institution responsible for the EIS evaluation. 4.1.1 Description One of the requisites of the
application developed by this project was its integration with the operational
system that was already implemented in the Environmental General Directorate.
This system gives support to the administrative procedures of the environmental
impact studies evaluation and uses an Oracle database, in which it stores data
about the identification and other descriptive data about the EIS. The support
system for the EIS evaluation has a connection to this database, retrieving
only the data needed for the EIS evaluation. The primary objective of the
EIS Support System was the automation, as much as possible, of the evaluation
process of the environmental impact studies, namely of the activities of
analysis for the determination of impacts. To fulfill this objective, the
system has these functionalities:
It was established a
workflow to guarantee the correspondence and integrity of the information
produced by the operational and the support system, namely between the spatial
and the alphanumeric components. The established workflow is made of the
following procedures:
During the development
process it was defined that the EIS Support System should satisfy three
requisites:
Figure 3 Integration of the Operational System with the EIS
Evaluation Support System The first requisite is
satisfied by the using the information that is stored in the operational
database. The second requisite is one of the hardest to fulfill because EIS are
very diverse and each of them has its own specific needs. The third requisite
was accomplished with the development of a user-friendly interface that
implemented the same way of working of the DGA staff and was integrated with
their office tools. Based on these requirements,
it was developed an interface with the basic functionalities of a browser of
geographical information and the specific requisites of the EIS evaluation
process. One of the constraints we faced was the potential lack of base and
thematic geographical information available to be used in the analysis process
and consequent EIS evaluation. The territorial scope of the support system is
the Portuguese continental territory. In many cases, it does not exist, digital
base and thematic geographical information and the specificity associated with
each EIS. This is the reason why the support system had to be very flexible to
include, in each case, the information needed and/or available. Even with this
flexibility, the support system should maintain a systematic and procedural
character. Another concern was the
access to the geographical information. We want it to be as much systematised
as possible. That is, the access to the information should be directed and
oriented accordingly to the objectives of the application - EIS evaluation. As
you can see in Figure 4, the interface of the application combines the
alphanumeric and spatial information relative to the EIS, which enables the
user to select the EIS with alphanumeric or spatial queries. Besides that, the
user can add thematic geographical data and choose which of them will be used
in the analysis process and what information will be produced.
Figure 4 – EIS Evaluation Support System interface To provide an easy and
direct access to the information, we have implemented another concept, which is
the Map Catalogue. The Map Catalogue
(Figure 5) is a level of geographical information and consists on a grid where
each cell corresponds to a sheet of the map. In the support system the users
just have to open the catalogue and select a cell of the grid to add or remove
the correspondent map sheet. The user can also control the visualisation
properties of the catalogue and define several map catalogues (geology, land
use, soils, topography, etc) but can only use one at a time. This way, the user
does not have to know the number of the sheet or where the geographical file is
stored, he just have to spatially select the sheets he wants to see. All the
information necessary to reference the sheets and about the map catalogue are
stored in a configuration file. The support system comes with a utility to
create and maintain the configuration file of the map catalogue. The process of the EIS
analysis and evaluation is implemented with a wizard, like many other windows
applications. The wizard is a Step-By-Step
tool in which the user indicates the themes geographical information that
should be used for the analysis. The user also indicates the information of
each theme. This method makes the process easier and more oriented. We only
have implemented a generic process of analysis and accordingly to the reaction
and suggestions of the users we probably will implement specific processes of
analysis, based on each type of EIS.
Figure 5 – Use of Map Catalogue The EIS Evaluation Support
System implements several types of reports. The reports can be the results of
the analysis of an EIS, the anual or periodic EIS evaluation activities or
relative to a specific EIS and based on the preferences of the user. These
reports combine the map and the descriptive information and can be directed to
a printer or to a document. The user also has the possibility of copying the
contents of the map and paste it in other application to create its own
documents. 4.2 Environmental Permitting
System DRA Alentejo is responsible
for licensing the use of the land under its jurisdiction and one of the many
functions of its technicians is to evaluate, if it is legal or not, to make a
specific use of an area in the region of Alentejo. This kind analysis can take
advantage from GIS technology, exploring in particular, the spatial database
and its inherent advanced analysis capabilities. The main objective of the
project is to simplify the decision making process by providing a simple
interface to a decision support system to DRA Alentejo technicians that allows
them evaluate every situation in a more effective and efficient way. 4.2.1 Description The DRA Alentejo technicians
use mainly the military topographic map at 1:25000 scale and, according to
several environmental legal constraints that are published in several sources,
takes the decision of authorizing, or not, the construction of a building or
factory, after checking if any of the environmental constraints is violated. The evaluation of
environmental constraints used to be made in a traditional way: a person who
wants to build, for instances, a building in Alentejo, needs to go to the DRA
Alentejo and ask if it is legal or not to build in that specific place. After
filling in several forms, they need to tell the technician where exactly is the
place and wait several weeks for the result of his evaluation. We are working on an
user-friendly interface that will enable the DRA Alentejo technicians, not
necessarily GIS specialists, to simulate and perform the evaluation of
environmental constraints in a very easy manner. Software to evaluate - what-if
- scenarios must be well designed and easy to use, to avoid disfunctional
separation of the roles of the analyst and decision-maker (Goodchild, 1993).
This is also one of our major concerns. After initializing the
program, the following interface appears (Figure 6). Here it is possible to
visualize the Alentejo map in Concelhos (administrative division) with the bold
border, and Freguesias (administrative subdivision of Concelhos) with the thin
border. There are 47 Concelhos and 295 Freguesias in Alentejo. This interface
has a toolbar with buttons with some basic functionalities like: Zoom In, Zoom
Out, Pan, Zoom to Full Extent and Identify. It also indicates the military
coordinates and the scale.
Figure 6 Alentejo in Map Objects
interface With the objective of
helping the user to locate the place where he wants to get information for, it
is possible to perform searches for the name of the Concelho or Freguesia using
a specific form. The 1:25000 scale raster military maps can be activated using
an image catalogue (Figure 7) created for these specific purpose. This way it
is possible to view only the image you want without the need of adding all the
images at the same time. Once it is loaded, it is also possible to perform a
search for the number of the military map. There are 212 military maps at 1:
25000 scale for the region of Alentejo.
Figure
7 Image
catalogue loaded with a SPOT satellite image from Sines After having located the place, the user can simulate the environmental constraints through a list box that allows to specify the type of implementation of the process: area (for instances if it is a building), line (for instances if it is a fence) or a point (for instances if its a well). After drawing the place where, for instances, the building is located, the | |||||||||
