Illustration of spatial analysis
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Spatial
Patterns in Soil Phosphorus and Primary Productivity in Arid
Ecosystems
My thesis addresses limits in knowledge about arid landscape
function by exploring the linkages between soil phosphorous
(P) distribution, productivity, and geomorphic factors at
the landscape scale. In developing and validating methods
for the spatial modeling of P, my research seeks to contribute
innovative approaches by assessing P remotely. In addition,
this research explores P's role in productivity via an analysis
of landscape patterns. Further, my thesis will examine a variety
of landscape factors correlated to productivity, such as soil
type, topography properties and substrate chemistry.
This project is funded by the USGS project Effects
of climatic variability and land use on American drylands |
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Model of channel changes of the Las Vegas
Wash, 1975-1999.
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Channel
change in Las Vegas, Nevada
Lower Las Vegas Wash was a typical desert wash before settlement
began in 1905. Upstream population has grown from about 5,000
in 1930 to about 1.6 million in 2004. Concurrent with a growing
urban center was increasing wastewater discharge to Las Vegas
Wash. Increasing amounts of wastewater added to the floodplain
eventually saturated the floodplain and created a large erosional
channel. This research applies spatial analysis and remote
sensing to examine the linkages between urban expansion and
changes in the hydrological system. Three sets of aerial photos
in a GIS document the geomorphic history of the Las Vegas
Wash, which drains the rapidly growing Las Vegas urban area.
New spatial techniques were used to make quantitative measurements
of the erosion at three specific time intervals in the hydrologic
evolution of the wash. The spatial analysis quantifies channel
changes for discrete time periods and provides a foundation
for further research to examine how the specific mechanisms
relate to urban expansions during discrete time periods.
This project was funded by the USGS
Earth Surface Processes Team.
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