Does livestock grazing influence spatial patterns of woody plant proliferation?

TitleDoes livestock grazing influence spatial patterns of woody plant proliferation?
Publication TypeConference Paper
Year of Publication2009
AuthorsBrowning D.M., Archer SR, Franklin J., Guertin D.P
Conference NameEcological Society of America Abstracts
Date PublishedAugust 2009
ARIS Log Number244074
Keywordserosion, grasslands, nutrient, savannas, spatial pattern
Abstract

Patterns of woody plant proliferation in grasslands and savannas influence rates of erosion, spread of disturbance, and nutrient pools.  Spatial pattern is the outcome of plant dispersal, recruitment, competition/facilitation, and disturbance. We quantified effects of livestock grazing, a widely cited driver of shrub encroachment, on the spatial patterns of velvet mesquite (Prosopis velutina) distribution and recruitment in southeastern Arizona.  Field surveys of plant canopy size and location spanning 74 years (1932, 1948, and 2006) were conducted on areas grazed by livestock since the late 1800s and on areas protected from livestock since 1932.  Point pattern analysis and Moran’s I were used to quantify changes in distribution and spatial autocorrelation over time.