Jason Williams

Dr. Jason Williams

USDA Agricultural Research Service, Southwest Watershed Research Center, Tucson, AZ 85719, USA
orcid

Research Focus & Metrics

Academic Career Length

19Years (2008-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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28 July 2009 in Hydrology and Earth System Sciences
Verified
Journal Article
Open access
PDF file
Jason WilliamsJason Williams
Jason Williams
JMJ. P. McNamara
J. P. McNamara
David ChandlerDavid Chandler
David Chandler
The controls on the spatial distribution of soil moisture include static and dynamic variables. The superposition of static and dynamic controls can lead to different soil moisture patterns for a given catchment during wetting, draining, and drying periods. These relationships can be further complicated in snow-dominated mountain regions where soil water input by precipitation is largely dictated by the spatial variability of snow accumulation and melt. In this study, we assess controls on spatial and temporal soil moisture variability in a small (0.02 km2), snow-dominated, semi-arid catchment by evaluating spatial correlations between soil moisture and site characteristics through different hydrologic seasons. We assess the relative importance of snow with respect to other catchment properties on the spatial variability of soil moisture and track the temporal persistence of those controls. Spatial distribution of snow, distance from divide, soil texture, and soil depth exerted significant control on the spatial variability of moisture content throughout most of the hydrologic year. These relationships were strongest during the wettest period and degraded during the dry period. As the catchment cycled through wet and dry periods, the relative spatial variability of soil moisture tended to remain unchanged. We suggest that the static properties in complex terrain (slope, aspect, soils) impose first order controls on the spatial variability of snow and resulting soil moisture patterns, and that the interaction of dynamic (timing of water input) and static influences propagate that relative constant spatial variability through most of the hydrologic year. The results demonstrate that snow exerts significant influence on how water is retained within mid-elevation semi-arid catchments and suggest that reductions in annual snowpacks associated with changing climate regimes may strongly influence spatial and temporal soil moisture patterns and catchment physical and biological processes.

23 January 2008 in Hydrological Processes
Verified
Journal Article
Closed access
PDF file
FPFrederick B. Pierson
Frederick B. Pierson
PRPeter R. Robichaud
Peter R. Robichaud
CMCorey A. Moffet
Corey A. Moffet
KSKenneth E. Spaeth
Kenneth E. Spaeth
SHStuart P. Hardegree
Stuart P. Hardegree
Jason WilliamsJason Williams
Jason Williams

1 July 2008 in CATENA
Verified
Journal Article
Closed access
FPF.B. Pierson
F.B. Pierson
PRP.R. Robichaud
P.R. Robichaud
CMC.A. Moffet
C.A. Moffet
KSK.E. Spaeth
K.E. Spaeth
Jason WilliamsJason Williams
Jason Williams
PCP.E. Clark
P.E. Clark

23 January 2009 in Earth Surface Processes and Landforms
Verified
Journal Article
Closed access
PDF file
FPFrederick B. Pierson
Frederick B. Pierson
CMCorey A. Moffet
Corey A. Moffet
Jason WilliamsJason Williams
Jason Williams
SHStuart P. Hardegree
Stuart P. Hardegree
PCPatrick E. Clark
Patrick E. Clark

1 November 2010 in Rangeland Ecology & Management
Verified
Journal Article
Closed access
FPFrederick B. Pierson
Frederick B. Pierson
Jason WilliamsJason Williams
Jason Williams
PKPatrick R. Kormos
Patrick R. Kormos
SHStuart P. Hardegree
Stuart P. Hardegree
PCPatrick E. Clark
Patrick E. Clark
BRBenjamin M. Rau
Benjamin M. Rau

7 August 2011 in Ecohydrology
Verified
Journal Article
Closed access
PDF file
Bradford WilcoxBradford Wilcox
Bradford Wilcox
LTLaura Turnbull
Laura Turnbull
MYMichael Young
Michael Young
Jason WilliamsJason Williams
Jason Williams
SRSujith Ravi
Sujith Ravi
JWJohn Wainwright
John Wainwright