Abstract: Land use change is closely related to the human disturbance. Dam construction alters the land use in the surroundings of the reservoir, and ultimately affecting the transport of matters from terrestrial ecosystem to the ocean through inland waters. Taking the Hongjiadu Reservoir in Wujiang River as an example, land use transfer matrix was applied to discuss the dam-induced change in land use in the catchment of Hongjiadu Reservoir at both the catchment scale and landscape scale. Results show that: (1) From the perspective of time scale, land use change mainly occurred in the second stage after reservoir impoundment. In the first stage, the overall change of Hongjiadu catchment was that the cropland area decreased by 91.33 km², while the forest, grassland, water and urban increased by 26.54, 8.84, 55.51 and 0.45 km², separately. In the second stage, the area of cropland, forest and grassland decreased by 230.98, 30.17 and 42.88 km² separately, while water and urban increased by 9.07 and 295.46 km² separately. (2) At the spatial scale, the land use change was mainly concentrated in the vicinity of Hongjiadu Reservoir, with the decrease of cropland and the increase of grassland; At the landscape scale of the reservoir, the land use type changed the most within the 0-1 km buffer zone, which was mainly manifested as water transferred to grassland, and urban transferred to cropland. Different land use types were inundated to form the reservoir area after the construction of Hongjiadu dam, which has the greatest impact on the land use change within the 0-1 km buffer of the reservoir.

Key words: land use conversion matrix, dynamic change, reservoir, buffer, catchment