Open Space Network Research Articles

The Design of an Urban Open-space Network for the City of Durban (South Africa)

Global urbanization is proceeding at an alarming rate and is threatening the long-term survival of many important biological resources. Planners in the City of Durban (South Africa), cognizant of this impending environmental crisis, have designed an urban open-space network aimed at preserving a representative and functional example of the previous indigenous landscapes now under threat as a result of development.Biogeographical principles have been used to produce for Durban a system characterized by maximized reserve size, continuity, and overall minimized system linearity with the lowest edge-to-area ratio possible. Emphasis has also been placed on economic viability and on the importance of community acceptance and participation within the system.

Biotope mapping and nature conservation strategies in urban areas of the Federal Republic of Germany

Two methods of biotope mapping and species recording in urban areas are presented. 1. (1) Selective biotope mapping in which only certain biotopes deemed worthy of protection are mapped. The examples presented here are the biotope mapping of Munich and the rapid biotope mapping of Düsseldorf. 2. (2) Comprehensive mapping, in which all biotopes found in the city are surveyed. Comprehensive mapping according to the method used in Berlin is described as an example. The evaluation of areas solely on the basis of selective mapping is considered to be inadequate because biotopes, especially in urban areas must be evaluated in the context of their surroundings. On the other hand, comprehensive mapping involves higher costs and more time and personnel. The recommendations of the “Working Group on Biotope Mapping in Settled Areas” are summarized. 3. (1) Comprehensive mapping should be given preference over selective mapping. 4. (2) The size of study sites in comprehensive mapping should be approximately 4 ha. 5. (3) A map scale of 1:5000 (in Berlin 1:4000) is suitable for field surveys. 6. (4) A clear distinction between built-up areas and the urban fringe must be made when data are being recorded. 7. (5) The recording of floristic, phytosociological and — whenever feasible — faunistic data must be on the basis of defined land-use types. 8. (6) Lists of flora should either be complete or include a defined selection. The present position of biotope mapping in the cities of the Federal Republic of Germany is given. Finally, the Species Conservation Program for the city of Berlin is cited, as an example where the results of surveys have actually been interpreted in terms of nature conservation strategies. In this respect, the following guidelines for urban development are of great importance: 9. (1) further use of land for building purposes must be minimized; 10. (2) consideration should be given to natural development in the inner-city area; 11. (3) the variety of typical urban landscape elements should be conserved; 12. (4) habitat differences should be preserved; 13. (5) a network of open spaces should be maintained; 14. (6) there should be functional integration of building in the ecosystems. The Species Conservation Program contains measures for the care and development of all urban biotope types. The measures for the biotope type “closed block building substance” are presented as an example.