In present-day geographical investigations there is often a demand for a large amount of detailed information on natural environment. That information is provided by topographical and thematic maps. To make such maps it is necessary to transform the information in a competent way and to bring it up-to-date. That can be done very efficiently using a new technology in the study of environment, viz. a technology related to the Geographical Information System.
The use of computers in geographical investigations is on the increase. It is therefore necessary to work out and adopt new methods of presentation of the results of those studies, particularly in graphic form. If cartographic presentation of the results of studies is required, it is important to select adequate methods of cartographic studies. It is therefore of great importance to formulate some directions of methodical character concerning the transformation of the contents and form of various kinds of information and to call attention to problems connected with measurements.
The importance of the cartographic research method for the development of GIS
Information concerning the geographical environment can be obtained as a result of observation and field measurements or by means of maps. However, observations and field measurements in large areas nowadays are very rare, since they can be easily replaced by measurements on maps (satellite pictures and other cartographic presentations), and by analysis, transformation and interpretation of their contents. Those are among the basic procedures in the cartographic research method (Geoinformation Research Method - GRM).
The cartographic research method is one of the most creative ways of practical and scientific use of maps in the process of geographical research (Saliszczew, 1973). Among the procedures most frequently used in that method are:
The above groups of procedures are generally used jointly and can be modified depending on the possibility of their being mechanized and automated. Those procedures partly coincide with the groups of technical methods distinguished by Berlant (1973) and can be used for studying phenomena using one map or a series of maps. In both cases the procedure consists in:
In the cartographic study method there are a number of methods of establishing correlations. However, in geographical studies, pointing out areas with more or less significant relationships between phenomena, i.e. areas where phenomena occur jointly, should often be more important than the calculation of the correlation coefficients. In that case the graphic form is enough to reveal the relationships between the phenomena under study, presented in the form of distinct thematic layers. That can be achieved by making numerical maps showing the relationships between sets of data, based on previously demarcated units of territorial reference.
Among the cartographic forms of presentation a good example of a method demonstrating the relationships between phenomena is the two-variable choropleth colour map (Olson, 1981 and Koziel, 1993)1. The two-variable choropleth colour map makes it possible to distinguish mixed territories by overlaying on each other two colours by which definite areas on the map are marked. The use of that method for the making of maps of joint occurence of phenomena involves transformation of the information contained in topographic maps.
Contemporary needs of transformation of information about the environment based on numerical models of the terrain require a selection of those of its characteristics which are most essential and thus best characterize the particular elements of the environment. In geographical studies the right selection of pairs of phenomena is of prime importance. The association and detection of interrelations between phenomena is particularly important, since the result of such studies is not infrequently the preparation of a map presenting "new substance". Such a map can be greatly helpful in further, even more thorough analyses.
The use of GIS in environment studies
Nowadays, considering the completely new quality of computer devices (16- and 32-bit supercomputers become more and more common), the analyses carried out in the framework of GIS will be considerably simplified, more detailed and, what is important, very much accelerated. Some methods previously worked out within the framework of CRM have a significant effect on the simplification of the above analyses e.g. in newly opened GIS laboratories maps are often subjected to analysis and transformation both graphical and mathematical-statistical. The contents of maps is frequently analysed by non-specialists, it can also be analysed by computer. e.g. the analysis of pictures based on the shapes of particular areas is one of the fundamental problems of interaction graphics and is essential in situations when decisions must be undertaken on the basis of form, i.e. the shape of the object (Pavlidis, 1987). In the case of maps, their similarity is best seen in the analogy of forms of contours, which have most frequently a patchy structure. The patchines of contours means that they make up various forms with rounded outlines on all sides. Different forms of contours are characteristic of different physico-geographical and natural-economic regions as well as of different features of those regions (Strzemski, 1971). That should be always kept in mind while doing this kind of work. The capability of understanding pictures is of a different kind than e.g. the capability of carrying out calculations. It is easy to understand and classify pictures of the type of portrait, landscape or satellite photograph, generally without consciously using controlled rules of procedure. That is why when conveying that skill it is not enough only to describe the rules of procedure - the algorithm, but it is necessary to present examples (Tadeusiewicz, 1984). In accordance with that direction, series of maps have been made by the two-variable choropleth colour map method in various aspects; those maps as sets of numerical data (hypsometry, average slope of terrain) stored in the computer’s memory can be subjected to the process of automatic recognition (Koziel, 1990).
The study of the environment by analysing the contents of maps (satellite pictures) by means of computers occupies an increasingly important position, and in future those procedures will certainly predominate over other research methods. To anyone who has ever had the opportunity to make a map professionally there is no doubt what instrument should be used for that purpose. That instrument is a GIS laboratory, adequately equipped with hardware and software.
A contribution to the development of GIS based on mini and microcomputers has been the development of software in, among others, the theory of photogrammetric elaboration of maps, map drawing, computer graphics, theory of cartography (cartology), geographical modelling, the topology of graph theory as well as in measurements and coding of data, data management systems or in computer assisted planning. On the other hand, 16 and 32-bit supercomputers (workstations) have contributed, particularly in recent times, to the development of GIS of the second generation (McLaughlin & Coleman, 1989) after (Taylor, 1991). The fully developed GIS of the second generation uses in the first place data obtained from the satellite ceiling. That is why among a number of attempts at defining what GIS is the most adequate seems to be the definition regarding GIS as the common part of teledetection, computer cartography, data bases management systems and computer assisted design (Maguire et al., 1994).
Although we observe, particularly in highly developed countries, an increasingly frequent use of achievements related to the so-called "artificial intelligence", it must be born in mind that an element of great importance in GIS technology is the staff operating the computer devices. Many even highly sophisticated and perfectly secured computer systems have to be worked in an adequately rational and intelligent way by specialized operators. That is particulerly essential from the point of view of compiling computer bases of data and using them.
Contemporary transformations and changes in natural environment have contributed to the formation of many different data systems or information systems. In connection with those systems (computer graphics) there has been an ever growing number of works of graphic character.
To denote all the maps, photographs and other similar models Berlant (1993a) puts forward the term "geoimages" understood as any four-dimentional scale, generalized model of terrestrial (planetary) objects or processes presented in a figurative graphic form. He distinguishes the following geoimages:
Considering the necessity of working out or developing many problems in the field of geoiconometry (those underlined in the following sentence), attention should be focused on them. Geoiconometry comprises the following items: geoplanimetry (cartometry, photogrammetry, morphometry, photometry, colorimetry), geostereo-metry (stereocartometry, stereophotogrammetry, stereomorphometry, stereophoto-metry, stereocolorimetry, hologrammetry), geochronometry (dynamic cartometry, dynamic photogrammetry, dynamic morphometry, dynamic photometry, cinecolori-metry, cinehologrammetry) (Berlant, 1993b).
The development of precise measurement methods based on all kinds of geoimages is of prime importance for the progres of the Earth science. A problem of equal importance is the adoption of uniform methods of measurements and field observations so that their results should be objective, reliable and comparable. It is therefore necessary and expedient to undertake adequate steps aimed at perfecting the above methods.
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