PS 13-101
Effects of grain size on topography-based landscape patterns: a case study of Wu'an, China
Topography, to a certain extent, determines local physical conditions as well as affects land use options, intensity and effects by human beings. Taking Wu'an of Hebei Province, China as a case study, this paper extracts topography-based landscape information through overlapping the elevation map and landscape pattern map.After a trial test, the elevation of study area is classified into below 200m, 200-300, 300-400m, 400-600m, 600-1000m and above 1000m. And then, various landscape indices are selected for analyzing the effects of grain sizes (from 30m to 300m with an interval of 30m) on landscape patterns.
Results/Conclusions
The research results show that (1) on the area at 0-200m above sea level, the optimal range of grain sizes for disturbance mainly lies between 0 to 210m, that for continuity and for sustainability both between 0 to 90m, (2) at 200-300m, the optimal range of grain sizes is restricted within 0-60m, for nearly all indices, (3) at 300-400m, the optimal ranges spread widely to 0-240m, 0-210m and 0-90m, (4) at 400-600m and 600-1000m, there is a similar but slightly different results to the area with an altitude of 300-400m, (5) one the area above the altitude of 1000m, the optimal ranges lie within 90-210m, 0-90m and 0-60m, respectively. Interestingly, the area at 200-300m are more sensitive to the effects of grain sizes, where human activities have a significant influence on landscape changes. The conclusions can benefit rational land use and optimal landscape allocation.