Topographic control on the present and past distribution of glaciers is indicated by close correspondence along the range between mean elevation and the modern equilibrium line altitude of glaciers (ELA) and differences in the modern ELA, mean annual precipitation and temperature across the range between the windward, southern and leeward, northern flanks.
Mean annual temperatures, reflecting latitude and elevation, range from about 56 °F (13 °C) in the south to 52 °F (11 °C) in the north and 48 °F (9 °C) in the most mountainous regions.
The mean elevation for the nine LMU classes ranged from an average low of 1,446 m for northerly canyons to an average high of neutral mid-slopes at 1,872 m (Table 1).
Across all models, the eight variables with the highest relative importance scores included: the number of geology classes (AICw = 0.99), calcareous bedrock (AICw = 0.83), latitude (AICw = 0.53), maximum elevation (AICw = 0.42), elevation range (AICw = 0.35), mean annual temperature (AICw = 0.20), average temperature of coldest month (AICw = 0.12) and acidic shale (AICw = 0.10).
Highly correlated variables; maximum elevation with elevation range (r = 0.99), and mean annual temperature with latitude (r = −0.92), substituted for each other in the top models, although latitude (0.52) was considerably higher in relative variable importance than mean annual temperature (0.20).
The mean elevation of surveyed households was also significantly lower in Abia (108.0 m; range: 11 m–351 m) versus Plateau (815.0 m; range: 117 m–1344 m).
The topography of the area is generally flat low laying and elevation range from about 0 m to 32 m above mean sea level (MSL).
The elevation range belonging to Qinghai spruce in Qilian Mountains was also determined according to the mean July temperature space occupied by the forest.
The elevation range is stretched to enhance the variation in elevation change inside the basin floor.
