Based on landscape pattern data in 1986 and 2000

terrain gradient characteristics of landscape pattern change in Guyuan County in the upper reaches of Jinghe River were quantitatively analyzed and discussed by using terrain niche index and transformation probability among the landscape types.Results showed that the whole landscape spatial pattern along terrain gradient was subject to little change during the late 20th century.Grassland and forest mainly occupied high terrain niches and other landscape types occupied low terrain niches.Meanwhile

there was regular variation in their distribution index values in different terrain niche zones because of the conversion and competition among the landscape types to a certain extent.The dominance degree of construction land on low terrain niches increased and the dominance degree of farmland decreased reversely

while the dominance degree of grassland on high terrain niches ascended and the dominance degree of forest descended correspondingly.Conclusively

human' s reconstruction on landscape patterns in Guyuan County focuses on low terrain niche areas so that the effects are not obvious and the unreasonable landscape structure being formed previously does not change significantly.