Abstract:Due to human over-exploitation and utilization in recent years, the landscape types of Tibet’s alpine mountains have been severely damaged. The landscape pattern index can effectively evaluate the evolution of landscape types on the time scale. Therefore, an object-oriented classification method was used to determine landscape types, and the diversity index, dominance index, uniformity index and aggregation index were selected as indicators to evaluate and analyze the ecological sensitivity of the study area. The grand canyon was selected as the study area, and the object-oriented classification method was used to algorithmically classify the Tibetan artificial disturbance zone. Finally, a total of 1761 patches of ten types of landscapes were obtained, of which the woodland landscape and grassland landscape with the largest areas, respectively were 48.84% and 22.68%, and the proportion of snow/glacier landscape was 17.39%. From the landscape index, the landscape diversity index in the study area was 1.374, the dominance index 0.982, the evenness index 0.597, and the polymerization index 97.374. The grand canyon research area had high diversity, the single landscape had a relatively low dominance, and the distribution of different landscape spaces was better. In general, the landscape in this area was dominated by virgin forests, alpine meadows and glaciers, with less disturbance of human activities, and was mainly concentrated in the conversion of farmland and grasslands in the valley. Based on the weighted analysis of the ecological sensitivity of the grand canyon study area, the six types of impact factors were combined. The ecological sensitivity was mainly concentrated in moderate and highly sensitive areas, with a total of 95.71%. Moderately sensitive areas were concentrated in low-altitude and low-slope areas around river valleys, and the land was mainly waters, grasslands and shrubs. Highly sensitive areas were concentrated in high-altitude areas of the mountains, with steep slopes. The landscape was dominated by woodland landscapes and glaciers/ice landscapes.
