Urban expansion analysis through Remote Sensing and GIS in Semarang-Indonesia

Urban areas and their expansion are important roles for the analysis of the urban ecological status, indicators for global ecological health, and sustainable development. Although urban expansion can improve the living conditions of the residents, it will also lead to various urban environmental and ecological issues. Semarang City is the center of a functioning metropolitan city of Kedungsepur (Kendal, Demak, Ungaran, Semarang Regency, Salatiga City, Semarang City and Purwodadi, Grobogan Regency) so that the development of various sectors in the Semarang City region shows a positive increase. This study aims to measure urban expansion and analyze its spatial patterns from 2005 to 2015 using remote sensing and GIS. The analysis method to measure urban expansion and developing patterns uses the urban expansion intensity index and local Moran's I, and quantification the typology of urban expansion. The results showed that the annual growth rate of urban expansion in Semarang city increased in the last decade, which was 2.7 km(2)/year (2005-2011) to 5.8 km(2)/year (2011-2015). The intensity of urban expansion is more dominated by low intensity followed by very rapid, moderate and rapid intensity. The results of Local Moran's I analysis also show the formation of urban growth clusters out of the city center that leads to the south. Between 2005 and 2015 the type of urban expansion was dominated by the type of edge expansion.