Recently fine dust is one of the biggest concerns in our society. Fine dust not only harms the landscape and blinds the view, but also causes critical damages to human health. The concentration of fine dust depends on regions and is influenced by various variables to some degree. Moreover, even though one is exposed to the same concentration of fine dust, the degree of risk from fine dust varies depending on one’s socioeconomic status.
In this regard, this study aims to examine the spatial distribution of fine dust in the city of Daegu, Korea and to investigate if there is an environmental inequity in the spatial distribution of fine dust. To do so, the Korea Environment Corporation(K-eco) and Korea Telecom Corporation(KT)''s fine dust measurement data were compared using the independent-samples t-test and combined. Four spatial interpolation methods such as Inverse Distance Weighted(IDW), Simple Kriging(SK), Ordinary Kriging(OK) and Univeral Kriging(UK) were performed and the Root Mean Square Error(RMSE) values were quantified and compared. Geographically Weighted Regression(GWR) was used to find out the environmental inequity in the spatial distribution of fine dust with respect to socioeconomic variables.
The results from this study can be summarized as follows. There was a small statistical difference between the K-eco and KT''s data. According to the result of the four interpolation methods, IDW showed the lowest RMSE value. From the IDW interpolation results, fine dust showed the highest concentration in Dalseo-gu and the lowest concentration in Jung-gu. GWR results showed better AICc and R2 values compared with those of Ordinary least Square(OLS). This means the regression relationship between fine dust concentration and socioeconomic variables in the city of Daegu showed a higher coefficient of determination in local regression and significant spatial non-stationarity. Although the analysis at the up-scale did not show statistically significant inequity between socioeconomic variables and the concentration of fine dust, the analysis at the down-scale showed statistically significant inequity. In other words, the environmental inequity analysis of fine dust in the city of Daegu confirmed that the Modifiable Areal Unit Problem(MAUP) occurred.
This study supplemented preceding studies by adding new measurement data such as KT data to compensate for insufficient location and method problem of K-eco''s fine dust monitoring system. However, the period between measurement data of fine dust and socioeconomic variables did not match, and weather and topographical factors were not taken into consideration. The results from this study can be used as basic data for reducing the fine dust concentration in the city of Daegu and providing better welfare benefits for residents who live in an area where inequity occurs.