Short-interval monitoring of land use and land cover change using a time series of RADARSAT-2 polarimetric SAR images

Abstract

With rapid growth in economy in the last two decades, cities in some rapidly developing regions in China, such as the Pearl River Delta, have expanded considerably. The demand for land for industrial and residential uses imposed increasing pressure on the management of agricultural and environmental sensitive land. Although a great deal of agricultural land was expropriated to meet the increasing land demand for residence and business, insufficiency of land supply still restricted industrial development in these regions. The insufficiency of land resource caused land prices to soar. As a result, many illegal land uses emerged in some rapidly developing places, such as urban fringes, in these regions. Due to the lack of effective monitoring tools, some illegal land uses have caused irreversible environmental problems, such as loss of farmland, forest degradation, soil erosion, and adverse effects on species diversity (Yeh and Li 1996). Serious environmental deterioration caused by urban sprawl poses a threat to healthy urban development. Short-interval, such as monthly, land use and land cover (LULC) change information is important for the government to control and prevent illegal land development at its early stage. Furthermore, it is also important in analyzing and simulating urban land development and assessing the ecological effect in different scales. Therefore, shortinterval monitoring of LULC change in these rapidly developing regions is much needed.