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University of Massachusetts Amherst

Bethany Bradley

Articles 1 - 3 of 3

Full-Text Articles in Environmental Sciences

Global Change, Global Trade, And The Next Wave Of Plant Invasions, Bethany Bradley, D. M. Blumenthal, R. Early, E. D. Grosholz, J. J. Lawler, L. P. Miller, C. J.B Sorte, C. M. D'Antonio, J. M. Diez, J. S. Dukes, I. Ibanez, J. D. Olden Jan 2012

Global Change, Global Trade, And The Next Wave Of Plant Invasions, Bethany Bradley, D. M. Blumenthal, R. Early, E. D. Grosholz, J. J. Lawler, L. P. Miller, C. J.B Sorte, C. M. D'Antonio, J. M. Diez, J. S. Dukes, I. Ibanez, J. D. Olden

Bethany Bradley

Many non-native plants in the US have become problematic invaders of native and managed ecosystems, but a new generation of invasive species may be at our doorstep. Here, we review trends in the horticultural trade and invasion patterns of previously introduced species and show that novel species introductions from emerging horticultural trade partners are likely to rapidly increase invasion risk. At the same time, climate change and water restrictions are increasing demand for new types of species adapted to warm and dry environments. This confluence of forces could expose the US to a range of new invasive species, including many …


Characterizing The Landscape Dynamics Of An Invasive Plant And Risk Of Invasion Using Remote Sensing, Bethany Bradley, J. F. Mustard Jan 2005

Characterizing The Landscape Dynamics Of An Invasive Plant And Risk Of Invasion Using Remote Sensing, Bethany Bradley, J. F. Mustard

Bethany Bradley

Improved understanding of the spatial dynamics of invasive plant species may lead to more effective land management and reduced future invasion. Here, we identified the spatial extents of nonnative cheatgrass (Bromus tectorum) in the north central Great Basin using remotely sensed data from Landsat MSS, TM, and ETM+. We compared cheatgrass extents in 1973 and 2001 to six spatially explicit landscape variables: elevation, aspect, hydrographic channels, cultivation, roads, and power lines. In 2001, Cheatgrass was 10% more likely to be found in elevation ranges from 1400 to 1700 m (although the data suggest a preferential invasion into lower elevations by …


Medusae Fossae Formation: New Perspectives From Mars Global Surveyor, Bethany Bradley, S. E.H Sakimoto, H. Frey, J. R. Zimbelman Aug 2002

Medusae Fossae Formation: New Perspectives From Mars Global Surveyor, Bethany Bradley, S. E.H Sakimoto, H. Frey, J. R. Zimbelman

Bethany Bradley

The nature and origin of the Medusae Fossae Formation (MFF) on Mars has been debated since the return of the first Viking images. The MFF's young age, distinctive surface texture, and lack of obvious source have prompted multiple hypotheses for its origin. This study uses data from the Mars Global Surveyor (MGS) mission to examine the MFF at all available scales. We discuss and quantify observations from Mars Orbiter Laser Altimeter (MOLA) topography and Mars Orbiter Camera (MOC) images to better constrain the origin of the MFF. Topographic grid estimates yield a present extent of 2.1 × 106 km2 and …