PL
Węzły ekologiczne jako obszary nie zabudowane a czynne biologicznie pełnią lub mogę pełnić w mieście rolę lokalnego zasilania i wzbogacania terenów otaczających, rolę hydrologiczną, klimatyczno-higieniczną i ekologiczną. W związku z tym powinny być nieodzownym elementem systemu przyrodniczego każdego miasta, a tym samym elementem jego struktury przestrzennej, powinny też znaleźć zapis w ustaleniach planów zagospodarowania przestrzennego. W artykule podano założenia wyjściowe tworzenia węzłów ekologicznych, ich rolę w mieście oraz sposób wyznaczania. Potencjalne węzły ekologiczne autorka wyznaczyła w Radomiu, Białej Podlaskiej i Białymstoku. Stwierdzono duże zróżnicowanie węzłów tak pod względem ich wielkości, położenia, jak i stopnia wewnętrznego urozmaicenia.
EN
In the physical structure of towns, a very important role is played by the open areas. To fulfil their functions, they should create a natural system shaped according to the principles of ecology. An indispensable element of the natural system in towns should be the ecological knots. The ecological knots are, those areas which exert a positive influence on their surroundings and which play or are able to play a role of local provision and enrichment of these surrounding areas. They shoulo be selected so that, in view of their peculiar features and values, they could and should play their role in the field of hydrology, climate, sanitation and ecology. The starting point for designation of ecological knots are the abiotic and next, biocenotic conditions. Potential ecological knots were designated within three towns: Radom, Biała Podlaska and Białystok (Fig. 1-3). Owing to this material, it is possible to present in this article the results of research in this field. Generally, it should be stated that the knots are considerably differentiated. In each of these towns there are various knots which differ in their size, situation and degree of their internal diversity (mosaic arrangement). Considering the situation of the knots, four types may be distinguished, namely: high plain type (watershed, slope, mixed), valley type, valley-high plain type and high plain-valley type. Fig. 4 presents four, selected as examples, ecological knots from the above mentioned towns, showing their dif- feret types. A proposition was submitted and proved that the differences among these knots, as well as their abiotic and biotic conditions are the result of the situation of these towns in various zones of Poland, showing different surface features. Ecological knots with a view to their functions, should be recognized as an element of the natural system of the town being equivalent to the element of the physical structure. This evokes a need for seeking in the town and in its surroundings the areas of potential ecological knots which should be registered in the plans of physical development, ensuring them proper forms of management.