저탄소 도시관리를 위한 온실가스 평가지표 개발 및 활용방안 = Development and Utilization of Greenhouse-Gas Evaluation Indicator for Low-Carbon Urban Management

다국어 초록 (Multilingual Abstract)

Seoul City needs to establish the foundation for more active low-carbon urban management in consideration of local characteristics in order to contribute to low-carbon green growth of the government and participate in international efforts to respond to climate change. In general, the items related to greenhouse gases in urban management plan includes only the calculation of yearly energy consumption and yearly CO2 emission per unit building and preparation of reduction plans, but does not include specific indices for low-carbon soil utilization. Especially, the items related to greenhouse gases are examined only for the building part and little has been considered for such carbon absorption sources as vegetation and soil that can bring in the indirect effect of emission reduction. The objective of this research is to analyze greenhouse gas emission of the building part in business districts on the basis of the urban regeneration project for accomplishment of low-carbon urban management, analyze the reduction by such carbon absorption sources as vegetation and soil, and then present a plan to apply a quantified target value related to greenhouse gases to low-carbon urban management in the future. The major contents of this research are as follows: First, the status of low-carbon urban management related to greenhouse gases was analyzed. Policies and standards practiced in relation to greenhouse gases were investigated in the position of the central government and Seoul City. At the same time, the cases for management and evaluation of greenhouse gases were examined in an effort to apply effectively the quantified target value developed in this research to low-carbon policies of Seoul City. Second, the current status of greenhouse gas emission was analyzed. The current status for urban management project of Seoul City was analyzed and the urban regeneration project was targeted for this research. The target sites of the urban regeneration project were classified into the residential environment improvement project and the urban environment improvement project for selection of specific target sites for analysis and estimation of greenhouse gas emission. For selection of target sites, the environmental impact evaluation project of Seoul City which can easily provide current data of business target sites was analyzed. Out of rearranged business target sites, some target sites whose basic data related to greenhouse gas emission analysis of the building part and vegetation/soil part required in this research was not sufficient were excluded and finally 10 target sites from each of the residential environment improvement project and the urban environment improvement project were selected. Greenhouse gas emission was analyzed after classification into building and vegetation/soil parts. For greenhouse gas absorption of vegetation and soil, existing formulae were reviewed and the single-tree formula used most generally in consideration of characteristic of the downtown area was selected, and for the building part the greenhouse gas emission was estimated from building emission sources fixed before and after business execution, Third, The results of each part were combined for evaluation, and an integrated analysis was made on greenhouse gas change classified by business target sites. For 10 target sites of the residential environment improvement project, combination of the storage and absorption by vegetation/soil and the emission from buildings indicates that, on the average, the carbon change per unit area was 70.48tonC/yearㆍha and the rate of carbon change 26.65%. The target sites from the residential environment improvement project were, on the whole, general residential areas of more than 2 or 3 kinds and some include semi-industrial areas or semi-residential areas, but the floor-area-to-land ratio was around 250% and the greenhouse gas change before and after business execution was relatively small with a maximum of 70.23% and a minimum of 0.87%. The absorption and storage of greenhouse gases by vegetation ad soil was found to be equivalent to 5 - 10 % of the emission of greenhouse gases from buildings. Thus, it is judged that active securing of vegetation and soil in the business districts can contribute to some degree to the reduction of greenhouse gases. In case of 10 target sites from the urban environment improvement project, on the average, the carbon change per unit area was 2,588.71tonC/year·ha and the rate of carbon change 1,168.62%, which indicate that the greenhouse gas emission increased a great deal compared with that of the target sites from the residential environment improvement project. The rate of carbon change for a considerable number of target sites was around 500%, and some target sites such as O district and L district showed the rate of carbon change was greater than 4,000%, which indicates that the variation between districts is seriously large, N district (2,098.58% increase) and R district (5,592.00% increase) where the rate of carbon change was severe are the cases where the carbon emission prior to business execution was remarkably low compared with other target sites and the rate of change increased. Comparison of real total carbon emission of these areas after business execution with that of other target sites shows a lower emission of the areas than the average emission per unit area, Thus, since the difference between these target sites and the other ones prior to business execution was large, an exceptional application is judged to be needed in case the target value of carbon emisson is developed in the future. In case of the urban environment improvement project, the storage and absorption of greenhouse gases by vegetation and soil were analyzed to reduce about 1% of the emission from buildings and so the reduction of greenhouse gases by absorption does not appear to contribute a great deal. Fourth, a target value related to greenhouse gas emission was selected and a specific plan to use it was presented. A specific target value was selected by combining integrated analytical results of building and vegetation/soil parts. For specific application of the developed target value (index), an environmental review from the urban management planning of Seoul City and items related to greenhouse gases from the environmental impact evaluation of Seoul City were considered to understand the current status, and evaluation standards and guidelines were presented to review relevant items in the future.