Condition of New Mexico rangelands derived from multi-year AVHRR imagery and associated spatial variables

TitleCondition of New Mexico rangelands derived from multi-year AVHRR imagery and associated spatial variables
Publication TypeConference Proceedings
Year of Publication1996
AuthorsLancaster J., Wade T., Minor T., Whitford WG, Jones B.
Conference NameProceedings of the 11th Thematic Conference and Workshops on Applied Geologic Remote Sensing
PaginationI-247 to I-256
Date Published1996
Conference LocationLas Vegas, NV
ARIS Log Number077978
KeywordsAVHRR, imagery, New Mexico, rangelands, spatial variables
AbstractThe Desert Research Institute in cooperation with the Environmental Protection Agency Characterization Research Division, Las Vegas, has been evaluating indicators of rangeland health derived from remote sensing technology. The primary objective of this project was to determine the ability of multi-date remote sensing imagery to detect variation in vegetation productivity, as a potential indicator of ecosystem condition in the western U.S. The conterminous U.S. AVHRR biweekly composites were acquired from EROS Data Center from the six year 1989-1994. Normalized Difference Vegetaqtion Index (NDVI) data for New Mexico were imported into a Geographical Information System. Using a digital vegetation map for the state, woodland and montane vegetation types were masked, leaving two grassland and four shrub-dominated vegetation classes. Average annual NDVI was calculated for each year, and a series of regression analysis were performed using 1989 as the reference year (independent variable), and each subsequent year as dependent variables. Outliers were identified as pixels two standard deviations from the calculated regression line, indicating 14 areas of change, three with lower productivity versus 1989, and 11 with higher productivity. Mining, military activity and irrigated agriculture were among the causes of change.