Geo-Spatial Approach for Urban Green Space and Environmental Quality Assessment: A Case Study in Addis Ababa City

Abstract

Depending on the rapid growth in infrastructural developments along with the increasing of human population, quality of cities is being deteriorated globally. Assurance of environmental quality is essential for urban planning and developments. This paper presents the potential application of urban green areas as an indicator of urban environmental quality in Addis Ababa, Ethiopia based on indicators of natural parameters extracted from remotely sensed images, and socio-economic variables derived from census data. Physical environmental variables such as land-use/land-cover data, surface temperature, normalized difference vegetation index, and transformed remote sensing variables derived from three landsat images of 1986, 2000 and 2015 were analyzed for the present study. Socio-economic variables including population density and greenhouse gas emission in 2012 were used. Regression analysis, factor analysis and overlay analysis were performed after the two groups of variables were integrated. Four factors such as greenness, crowd, heat island and greenhouse gas emission were used for interpretation. By assigning different weights to each of these factors and proportion of green areas, land-use/land-cover map, environmental risk map and environmental quality index map were generated. The results show deterioration of environmental quality in the study area. It is recommended that future studies should include more parameters to provide a holistic view of the changes in greenness of the city and to try to mitigate adverse effects of development activities leading to human density and depletion of green area in the city.