Abstract: Landscape fragmentation resulting from the development of road network has become a hot issue in road ecology. To quantify the spatial pattern of road network and its cumulative effects on adjacent landscapes is essential for the assessment of ecological consequences of road construction.Taking the core area of Pearl River Delta in Guangdong Province of South China as a case and by using kernel density estimation (KDE) method and road density index, this paper approached to quantify the spatial pattern of road system and its correlations with landscape fragmentation. KDE method could effectively identify and collect the hot regions of high density road network. The analysis of road density index showed that there existed strong correlation between road density and landscape fragmentation. The combination of road density and KDE method could overcome the limitations of road density calculation based on administrative boundaries traditionally, providing a better quantitative tool to study the characteristics and landscape fragmentation of road network.

Key words: irrigation methods, rice, apparent quality, eating quality.