Abstract:Regional ecological pattern and process are influenced by the existence and extension of road networks. As road is an intrinsic disturbance factor in landscape, the study of the relationship between road features and its disturbance level is important to regional ecosystem management. We analyzed the characteristic indexes of road network and their relationship at the county scale and further sought the regularity between the index and region ecological disturbance using GIS and network methods. The results showed that the indexes of road network, such as road connectivity nodes number, line number, α circuitry index, β line-node ratio, and γ connectivity index, varied greatly in Lancang River Valley. Road density and road length are negatively correlated with regional elevation. Road density has a positive relation with road corridor number, α connectivity index, β line-node ratio, and γ circuitry index. Linear regression can simulate the relation between road density and line number density while the relationship between road density and α, β, γ indexes can be modeled by reciprocal model. Buffer analysis showed that the percentage of farmland type is significantly linearly correlated with road density while other types have no significant relationship. Human disturbance index (Hd), patch density and average patch area (1980, 2000) have a significantly positive relationship with α, β, γ indexes which suggest the ecological disturbance increased and ecosystem fragmentation was intensified with the network expanding. However, the correlation between ecological change and road network index was not significant in relatively short period.