Urbanization Driving Forces of Unexploited Land Conversion in Ecologically Fragile Karst Areas of Southwest China:A Case Study of Guiyang City

Urbanization is regarded to be one of the most important factors driving land use change. In this paper, through an integrated technique of RS, GIS and GPS, unexploited land conversion has been unveiled from 1996-2010 in Guiyang and further examination has been made on the impact of urbanization on unexploited land change. And based on the adjustment of Markov process, land use transition probability and CLUE-S parameters, many scenarios of unexploited land changes in the study area have been simulated. It is found that: (1) the unexploited land in Guiyang has experienced complex changes due to the rapid social and economic change since 1996. It showed a declining trend generally and was reduced from 74.33 km² in 1996 to 65.72 km² in 2010, a reduction of 8.61km² in 14 years. It has a close relationship with the rapid development of urbanization. (2) The urbanization comprehensive parameter (k) showed growth from 2.91% to 4.78% after urbanization development indicators were standardized during 1996-2010. (3) Regression analysis was used to unveil the relationship between urbanization and unexploited land. There was a significant correlation between them, which proved that the urbanization is one of the dominant factors to lead to exploited land change. (4) The unexploited land will show a significant decreasing trend in the coming 20 years, the conversion-out area will be larger than the conversion-in area in three scenarios and the gap will be widened gradually year by year. During multi-scenario simulations, unexploited land area decrease in ecological protection scenario is most prominent, the proportion of unexploited land converted to construction land in economic development scenario is the largest, and the area of grass land becoming unexploited land in unchanging trend scenario is the largest.