Reconnaissance satellite photos show the recent history of shrub recruitment and survival in desert grasslands

TitleReconnaissance satellite photos show the recent history of shrub recruitment and survival in desert grasslands
Publication TypeConference Paper
Year of Publication2000
AuthorsGoslee S.C., Peters DC, Havstad K, Schlesinger W.H.
Conference Name85th Annual Meeting, Ecological Society of America
Date PublishedAugust 6-10, 200
Conference LocationSnowbird, UT
ARIS Log Number110161
Keywordsdesert grasslands, history, Larrea tridentata, prosopis glandulosa, reconnaissance, satellite, shrub recruitment
AbstractCertain shrub species, particularly Prosopis glandulosa and Larrea tridentata, have increased dramatically in the southwestern US during the past few decades, replacing the original grassland vegetation. We obtained a temporal series of high-resolution military satellite images beginning in the early 1960s, with the goal of monitoring shrub invasion over a large area to determine the topographic and climatic controls on shrub seedling establishment and the rate of expansion of shrub cover. Although the total area of shrub cover increased over time, both the number of shrubs and their size distributions were highly variable. Mortality in small shrubs was high, but once shrubs reached a threshold size, they were likely to persist for long periods. Shrub establishment and survival were related to both climatic factors and topographic features, particularly precipitation and drainage. Our results provide valuable information for those interested din the management and restoration of the desert grasslands of the southwestern US.