Ankara'nın Kentsel Metabolizması:Eryaman Bölgesinde 3B CBS İle Stoğa Net Katkı (SNK) İndikatörü Tahmini

Abstract

The need for materials in the built environment and the amount of waste that may be generated in the future due to this consumption is one of the serious problems of urbanization. The energy required for the production of construction materials constitutes a significant part of the total energy need of the society. Promotion of the transition to more environmentally friendly construction materials in the construction sector, reduction of material use and consumption of natural, local and recyclable materials are important in terms of resources, energy and waste management. Urban metabolism studies play an important role for determination of urbanization trends and identification of relevant environmental problems. These studies, using inputs required for the functioning of a city, accumulations and outputs in the system are gathered in a systematic way and the indicators related to the metabolism of interest are calculated. One of the indicators of urban metabolism is Net Additions to Stock (NAS). NAS indicator refers to the transformation of inputs and the material and energy stored in the system after outputs are removed from the system. NAS indicator is an indirect measure of the economic growth of the urban area. Parallel to the global trend of urbanization, urbanization has a rapid upward trend for provinces of Turkey that have high in, presence of industry, commerce, tourism and services sectors. Among these provinces Ankara is a the city that has one of the greatest number of buildings. In the scope of this study, NAS indicator for Etimesgut county and Ankara city was estimated based on exploration of a pilot area in Eryaman district of 7,34 km2 using Material Flow Analysis (MFA) method for the years 1998 and 2015. The difference in net additions to stock between 1998 and 2015 were examined. Results show that the pilot area has an area of 4,59 km2 in 1998 and 5,8 km2 in the year 2015 with an increase of % 20,86 in built-in environment. According to the findings, the material stock, which was 7,81 megatons in 1998, increased by 2,02 megatons to reach a total of 9,83 megatons in 2015. NAS indicator for Ankara was estimated to be 76 tons/person for the year 2015 by extrapolating results of the pilot area using population density per area as an indicator. As a result, it has been observed that the 7,34 km2 area of Eryaman district, which was selected as the pilot urban area. At the end of the expected lifetime of the buildings, for the year 2015 the amount of total waste generated is, 9,83 megatons of material and 7,68 megatons of the total amount is recyclable building material. The amount of embodied energy caused by the structures was calculated and compared with the value in the literature. The total embodied energy calculated for 1998 and 2015 is 16.756 TJ and 21.161 TJ respectively. The amount of embodied energy for residential buildings per square meter is found as 3,6 GJ. This value is closer to the lower limit of the range of 3-8 GJ provided in the literature.