Mapa zasięgu widoku okolic Pińczowa

W artykule przedstawiono możliwości pomiaru zasięgu widoku i ich wykorzystania w badaniach geograficznych. Zasięg widoku był obliczany na podstawie specjalnie do tego celu opracowanego programu komputerowego. Analizę przeprowadzono dla obszaru 77 km(2) w okolicach Pińczowa. Jej efektem jest pierwsza w Polsce i jedna z pierwszych w świecie mapa zasięgu widoku.

---

The instruments or methods which present and help to interpret three-dimensional space belong to the considerably new means of applying GIS techniques. Methods of determi- ning view range seem here to be of particular interest. View tests can be carried on in two basic aspects: as exploration of individual scenes or as investigation of the same landscape; only one observed from different locations. The result of the first approach will be a general characterization of the scenic view. The identification of invariant basic observation points can take place by creating a geometric grid or by selecting specific points at characteristic sites such as crest-lines, hill summits etc. According to the second approach one gains an answer to the question concerning the point from which a specific (for instance the most attractive) perspective on a given landscape is available. One can also identify the observation points where specific landscapes or its components (such as a river, mountain top, smoke stack) can be seen. In addition to this the landscape components i.e. its content are visible in different positions mutually. This of course has also an impact upon further analysis. The investigated area should be deli- mited by natural borders or barriers which cover the view such as crest- -lines, forest lines. The identification of view range is not to be attempted in forested or built-up areas. In the field of view investigation one can also identify a structural aspect, when analysis concerns the situation of landscape components and a fun- ctional aspect, when one considers the functioning of the landscape and the changes of its physiognomy over time. The proposed method of view range measurement can be defined as testing whether the site observed is hidden behind a certain point on the surface of the given territory. The area of study should be covered by a suffi- ciently dense network of points from which an analysis of the field of vision is carried out. These points should normally be located in the centre of the area under study. Otherwise the range of the field of vision can extent beyond the field of study and the result of the analysis can be erroneous. Such an analysis is only relevant when our interest is focused on just one element of the view (for example one-directional view). The empirical analysis was carried out in the vicinity of the town of Pińczów, situated in southern Poland, 50 kms south of the city of Kielce. The area of investigation covered 77sq. kms (7 x11kms), the area of observation was 8 sq. kms. For the purpose of the analysis a three-dimensional model of land cover including wooded areas, built-up areas etc. was elaborated. The computer programmes applied were WinSurfer for Windows and Atlas GIS. The model has included a square grid of side lenght of 50 metres (there were 31161 nodal points all together and there were 3241 points from which the view range was being determined). The view range was measured on the basis of an algorithm specially developed and written in the program- me Visual Basic. The algorithm was used to test the view range between each pair of points on the grid, at the height of 1.7 metres above ground. As a result a set of individual points was received, characterized by specific values of the view range. A map was elaborated on this basis using the MapInfo computer programme. The areas from which the view range is less than 10 sq. kms account for 35.8% of the total model area, the area of the view range of between 10 and 20 sq. kms amount to 15.8%, between 20 and 50 sq. kms, to 8.7% and the area of the view range of above 50 sq. kms represent 12.2% of the total area under study. Determination of the view range can find various applications. Such an analysis can undoubtedly be used to estimate the aesthetic value of the landscape. It can also be used for the purpose of spatial development, construction, tourism, recreation, as well as for practical field orientation. An analysis of the view range, as carried in to estimate the aesthetic value of landscape should be considered in two aspects: in the context of visual attractiveness of individual regions (natural landscapes, as well as natural and cultural landscapes) and in the context of visual attractiveness of individual views. These two elements are mutually complementary and therefore the two approaches should be considered jointly.