Abstract: Large-scale construction of road affects landscape pattern around, and also, ecological process directly or indirectly. Taking the Red River watershed in Yunnan Province as a case, and by using GIS and RS technology, this paper analyzed the effects of road on landscape pattern and soil erosion, and, through the calculation of landscape ecological risk indices based on landscape pattern and process, approached the landscape ecological risk pattern under road network expansion. In the Red River watershed, the landscape types near roads were mainly arable land, woodland, and meadow, and the landscape ecological risk indices based on the landscape pattern of woodland and meadow generally decreased with increasing distance to roads, suggesting that the landscape patterns of woodland and meadow were influenced obviously by roads. The soil erosion modulus in the buffer zones of the first-class roads, third-class roads, and fourth-class roads decreased with increasing distance to roads, and the third-and fourth-class roads were widely distributed, more easily to be eroded. The landscape ecological risk index based on the landscape pattern and process had a certain positive correlation with road density in spatial distribution.

Key words: Wheat-corn intercropping agroecosystem, Features of energy flow