

Scientists Eye Farm Uses of Landsat 7
ImageryBy Marcia
Wood April 16, 1999Information beamed to earth from the
Landsat 7 satellite launched from California yesterday will be eagerly
scrutinized by Agricultural Research
Service scientists. Researchers in Arizona are exploring ways that growers and land managers of
the future could routinely use imagery from satellite data for precision
farming, sometimes called foot-by-foot management. The imagery might help
growers answer crucial questions in time to act quickly to prevent crop losses
or bolster profits. For example, are crops getting enough water? Are they under
attack by diseases? At the U.S. Water
Conservation Laboratory in Phoenix, Ariz., ARS physical scientist M. Susan
Moran and colleagues are improving a method for combining data from five
satellites. Landsat 7's on-board sensor will supply two forms of data--heat
emitted from and light reflected by plants and soil, for example. The other
data are from radar sensors on four other satellites. The heat, light and radar-based technologies complement each other and
should open the door to providing useful imagery to growers on a daily basis,
according to Moran. Landsat 7 will pass over a given spot only once every 16 days, but the gaps
can be filled by radar data collected nearly every day. On overcast days, radar
can "see" through clouds that thwart Landsat 7. And Landsat's
eight-band sensor provides more detailed crop and soil information than the
one-band radar sensors. Landsat 7 is expected to provide more accurate data--and with a faster
turnaround--than its predecessor, Landsat 5. The National Aeronautics and Space
Administration is funding part of Moran's work. She is a member of the
Landsat 7 science
advisory team and the principal ARS scientist for Landsat 7. Other ARS
scientists in Arizona and ARS labs in Beltsville, Md., will also conduct
experiments with Landsat 7 imagery. ARS is USDA's chief research agency. Scientific contact: M. Susan Moran, ARS U.S. Water Conservation
Laboratory, Tucson, Ariz; phone (520) 670-6380, ext. 171; fax (520) 670-5550;
[email protected],
http://www.tucson.ars.ag.gov/rsg/landsat.
Story contacts Marcia A Wood U.S. Department of Agriculture | |