سیستم کارشناسی برای شناسایی اثرات زیست محیطی بر اساس سیستم های اطلاعات جغرافیایی

The identification and assessment of the environmental impacts of engineering projects is an essential step in studies on environmental impact (IES). There are methods that allow both tasks to be performed and methods that allow each of them to be carried out separately. Normally, traditional methods are used to identify and evaluate environmental impacts, such as matrices, cause-effect network diagrams or check lists. Here we report the configuration of an expert system as a tool that allows environmental impacts to be identified. The expert system is based on a geographic information system to configure the knowledge base, the inference motor and the user interface. The knowledge base comprises declarative knowledge (structured in an alphanumeric and spatial database from official cartographic information) and procedural knowledge (via heuristic rules that superimpose project actions over environmental factors). We then describe the application of the expert system to the study of the environmental impact of the R-3 motorway in the Community of Madrid, Spain. As results, running the expert system allows the identification of environmental impacts on environmental factors defined at the 1:5000 and 1:25000 cartographic scales. Finally, analysis of the results or conclusions allows the validity of the use of graphic expert systems to be compared for the identification of environmental impacts.

1.1. Background This work is related to two avenues of enquiry: on one hand, the use of computer-generated models and the development of software for the identification and assessment of environmental impacts and, on the other, the application of geographic information systems for the identification and evaluation of environmental impacts. Within the context of research into models and software development, the first IMCA (Gómez-Orea et al., 1990) and IMPRO (Gómez-Orea et al., 1991) models are very important, as is the later improvement with the IMPRO 3 (Gómez-Orea, 1999). In this sense, emphasis should also be placed on the proposal of a “Metalanguage for the Evaluation of Environmental Impact” (Pereira, 1999) or “AIEIA: software for fuzzy environmental impact assessment” (Blanco-Morón et al., 2009). Regarding the application of GIS to the identification and assessment of environmental impacts, contributions addressing the role of the spatial dimension of environmental impact and the assessment of their importance are relevant (Antunes et al., 2001 and Vanderhaegen and Muro, 2005). As well as the above research framework, this work also addresses the following issues: (1) the strong dependence of the assessor (or expert) in the identification of environmental impacts by the methods usually employed to measure them (matrices, network diagrams, check lists); (2) the spatial issue is not addressed in traditional methods assessing environmental impact (in this sense, the actions of projects are not usually represented cartographically, neither are comparisons found between situations “with” and “without” projects by cartographic representation); (3) the elaboration of digital cartographic information in a study addressing environmental impacts is costly. 1.2. Hypothesis approach In light of the foregoing, the present research aimed at the configuration of an expert system able to identify environmental impacts. To accomplish this, it was necessary to consider the spatial component of the environmental information. To do this, the actions of the project, and the environmental factors were represented cartographically and “with” and “without” project situations were analyzed by means of a geographic information system (GIS). Additionally, the cartographic information about environmental factors came directly from numerical cartographic bases or cartographic series in digital form elaborated by the corresponding official cartographic agencies.

6.1. Main contribution The present work provides a new way to identify environmental impacts based on algorithms of graphic overlapping between the actions and the environmental factors by direct use of official cartography in digital format as part of the environmental inventory. It goes beyond the simple consideration of a GIS in the identification of environmental impacts as a useful technology for the overlapping of topology maps since it proposes the configuration of an expert system able to identify, on its own, environmental impacts. The software used in the verification test allows direct use of the graphic data base of the Community of Madrid. With the programming carried out for the verification test, it is possible to construct a complete expert system, although it is necessary to modify the way in which part of the graphic information generated by the Community of Madrid is arranged, and perhaps a more efficient programming would be required. The essentially graphic nature of the system certainly suggests that the selection of information through its graphic attributes allows the same degree of use of the graphic information as the selection of information through the thematic data base. Additionally, the selection of information through the graphic database avoids complicated thematic databases (i.e., it is not necessary to configure the automatic cartography system according to features and categories, as done in the verification test). Accordingly, it is necessary to operate with the graphic attributes established by the CAD program. The possibility, adopted here, of being able to define the actions according to the level of detail allows the expert system to be used as an assessor of possible environmental impacts. 6.2. Secondary contributions Regarding secondary contributions, the digital information of the cartographic files of the Community of Madrid requires the transformation of certain complex graphic elements (for example, multilines and area shapes with holes) into simpler ones for treatment with the expert system. Additionally, the vast amount of information of some thematic layers of the files of the Community of Madrid (for example, buildings) requires treatment according to smaller areas than those of the corresponding map. In the opposite case, the GIS program may become blocked. 6.3. Unresolved issues Among the aspects that remain to be clarified here is the incorporation of a thematic attribute into the degree of certainty in the identification of environmental impacts (although this was not dealt with either in the study of the real environmental impact of the R-3). Neither have we considered in the information concerning the environment the so-called critical aspects that will specify the different risks deriving from natural and or confluence conditions of certain activities with respect to the environment.