Description |
The primary objective of this thesis is the cartographic representation of the dominant plant cover types, and a spatial interpretation of the zonal community types , within the upper Bear River drainage. The upper Bear River drainage is located within the western section of the Uinta Mountains, Utah. Two maps, titled "Plant Cover Types, Hayden Fork," and "Plant Cover Types, upper Bear River." were compiled. The two maps were prepared from data derived from field work, aerial photographs at a nominal scale of 1:15,840, and a photo-mosaic. Four broad steps were carried out in the preparation of the maps: (1) reconnaissance of the vegetation units to be mapped; (2) analysis and interpretation of the plant types from aerial photographs; (3) ground checking, which consisted of using transects and quadrants in determining plant cover frequency, transition belts, and boundaries; and (4) construction of the maps through the process of expansion and reduction by proportional squares. Six zonal community types were recognized in the upper Bear River drainage; krummholz, one of the cover types included, is a physiognomic type. Altitudinal distribution of the six zonal cover types are: (1) sagebrush from the Wyoming Basin to 9,800 feet, (2) quaking aspen to an upper altitudinal limit of 9,200 feet, (3) lodge-pole pine from 8,000 to 9,600 feet, (4) spruce-fir from 9,600 to 11,000 feet, (5) krummholz from 10,400 to 11,600 feet, and (6) alpine tunlra from 10,600 feet upward. Under optimum conditions timberline was found to be 11,000 feet and mean timberline in the study area was determined to be 10,500 feet. The upper lints of krummholz was observed at 11,600 feet. Lodge-pole pine was not found to be a component of krummholz, nor were cones found on any of the krummholz stands. |