Historical Analysis of Land Cover/Condition Trends at Fort Bliss, Texas, Using Remotely Sensed Imagery

摘要

Fort Bliss, Texas, is a Training and Doctrine Command installation located in the semi-arid Northern Chihuahuan Desert of Western Texas and South Central New Mexico. Military training (both tracked and wheeled vehicles), grazing, and recreational activities act as stressors on the landscape. The natural resource managers need information on land condition to make informed land management decisions and to support conservation and compliance efforts. They need a cost-effective method of assessing and monitoring land condition. The objective of this research was to characterize the small scale, gross level change in land condition on a selected area of Fort Bliss over a 23-year period. The evaluation and analysis was based on several vegetation and brightness indices calculated from temporal, archival multispectral imagery. Trends in brightness and greenness indices varied considerably. Most variation could be due to natural differences in the amount of precipitation in the region. There was no indication of permanent, long-term changes in the land condition. The study area appeared to be resilient, with no clearly observable trends in either long-term degradation or improvement. The brightness and greenness indices calculated from temporal image data sets provides a cost-effective method for monitoring relative trends in land condition.