Based on the data source of the remote-sensing images of Landsat TM in 1990-2011, object-oriented ENVI method and Google Earth were used to analyze the land cover as well as spatial distribution patterns of natural river networks and artificial ditches. Combined with the annual precipitation and temperature data in 1967-2012, the impact of climatic change on land cover was analyzed. The results show that the area of construction land and desert in 2011 is 5.84 and 1.35 times of that in 1990, respectively. Forestland area decreased with a rate of 0.66 km²/a under the influence of population increase and human activities. Water surface area was in a fluctuating variation due to the influence of both hydrological cycle and precipitation. Grassland area always increased, in which the vegetation coverage decreased first and then increased. The peatland swamps rapidly shrank at a rate of 78.62 km²/a due to the combined effects of climatic warming, artificial ditches and headward erosion of natural river networks. There are two primary dewatering patterns of peatland swamps in Zoige Plateau, dewatering by artificial ditches and joint dewatering by both natural river networks and artificial ditches. Persistent dewatering by artificial ditches significantly influences the water storage capacity, restricts the maintenance of peatland swamps and accelerates their shrinkage.