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Identification of saline soils with multi-year remote sensing of crop yields

Description: Soil salinity is an important constraint to agricultural sustainability, but accurate information on its variation across agricultural regions or its impact on regional crop productivity remains sparse. We evaluated the relationships between remotely sensed wheat yields and salinity in an irrigation district in the Colorado River Delta Region. The goals of this study were to (1) document the relative importance of salinity as a constraint to regional wheat production and (2) develop techniques to accurately identify saline fields. Estimates of wheat yield from six years of Landsat data agreed well with ground-based records on individual fields (R{sup 2} = 0.65). Salinity measurements on 122 randomly selected fields revealed that average 0-60 cm salinity levels > 4 dS m{sup -1} reduced wheat yields, but the relative scarcity of such fields resulted in less than 1% regional yield loss attributable to salinity. Moreover, low yield was not a reliable indicator of high salinity, because many other factors contributed to yield variability in individual years. However, temporal analysis of yield images showed a significant fraction of fields exhibited consistently low yields over the six year period. A subsequent survey of 60 additional fields, half of which were consistently low yielding, revealed that this targeted subset had significantly higher salinity at 30-60 cm depth than the control group (p = 0.02). These results suggest that high subsurface salinity is associated with consistently low yields in this region, and that multi-year yield maps derived from remote sensing therefore provide an opportunity to map salinity across agricultural regions.
Date: October 17, 2006
Creator: Lobell, D; Ortiz-Monasterio, I; Gurrola, F C & Valenzuela, L
Partner: UNT Libraries Government Documents Department

Water Rights Related to Oil Shale Development in the Upper Colorado River Basin

Description: Concerns over fluctuating oil prices and declining petroleum production worldwide have revived interest in oil shale as a potential resource. The Energy Policy Act of 2005 (P.L. 109-58) identified oil shale as a strategically important domestic resource and directed the Department of the Interior to promote commercial development. Oil shale development would require significant amounts of water, however, and water supply in the Colorado River Basin, where several oil shale reserves are located, is limited. This report will provide a brief overview of water rights in Colorado, Utah, and Wyoming, including changes that may be made to currently held water rights and the possibility for abandonment of unused water rights.
Date: November 18, 2008
Creator: Brougher, Cynthia
Partner: UNT Libraries Government Documents Department

Quadrula houstonensis, Specimen #1427

Description: One preserved mussel specimen including both the left and right valves. The specimen exhibits a round shape; white internal coloring; brown external coloring; no external sculpturing. The specimen measures between 100 - 120 mm in length and was assessed to be recently dead when collected.
Date: unknown
Partner: Elm Fork Natural Heritage Museum

Quadrula houstonensis, Specimen #1428

Description: One preserved mussel specimen including both the left and right valves. The specimen exhibits a round shape; white internal coloring; brown external coloring; no external sculpturing. The specimen measures between 60 - 100 mm in length and was assessed to be recently dead when collected.
Date: unknown
Partner: Elm Fork Natural Heritage Museum

Quadrula houstonensis, Specimen #1429

Description: One preserved mussel specimen including both the left and right valves. The specimen exhibits a round shape; bluish-white internal coloring; brown external coloring; no external sculpturing. The specimen measures between 60 - 100 mm in length and was assessed to be recently dead when collected.
Date: unknown
Partner: Elm Fork Natural Heritage Museum

Quadrula houstonensis, Specimen #1430

Description: One preserved mussel specimen including both the left and right valves. The specimen exhibits a round shape; white internal coloring; tan external coloring; no external sculpturing. The specimen measures between 0 - 60 mm in length and was assessed to be recently dead when collected.
Date: unknown
Partner: Elm Fork Natural Heritage Museum

Quadrula houstonensis, Specimen #1431

Description: One preserved mussel specimen including both the left and right valves. The specimen exhibits a round shape; white internal coloring; brown external coloring; no external sculpturing. The specimen measures between 0 - 60 mm in length and was assessed to be very-recently dead when collected.
Date: unknown
Partner: Elm Fork Natural Heritage Museum

Quadrula petrina, Specimen #1525

Description: One preserved mussel specimen including both the left and right valves. The specimen exhibits a round shape; white internal coloring; off-white external coloring; no external sculpturing. The specimen measures between 60 - 100 mm in length and was assessed to be relatively-recently dead when collected.
Date: unknown
Creator: Singley, J. A.
Partner: Elm Fork Natural Heritage Museum

Quadrula petrina, Specimen #1420

Description: One preserved mussel specimen including both the left and right valves. The specimen exhibits an oval shape; white internal coloring; brown external coloring; no external sculpturing. The specimen measures between 100 - 120 mm in length and was assessed to be recently dead when collected.
Date: unknown
Partner: Elm Fork Natural Heritage Museum

Lampsilis hydiana, Specimen #1447

Description: One preserved mussel specimen including both the left and right valves. The specimen exhibits an oval shape; white internal coloring; tan external coloring; no external sculpturing. The specimen measures between 0 - 60 mm in length and was assessed to be relatively-recently dead when collected.
Date: unknown
Creator: Walker, J. B.
Partner: Elm Fork Natural Heritage Museum

Quadrula aurea, Specimen #1396

Description: One preserved mussel specimen including both the left and right valves. The specimen exhibits a round shape; white internal coloring; tan external coloring; no external sculpturing. The specimen measures between 0 - 60 mm in length and was assessed to be relatively-recently dead when collected.
Date: unknown
Partner: Elm Fork Natural Heritage Museum

Truncilla macrodon, Specimen #1457

Description: One preserved mussel specimen including both the left and right valves. The specimen exhibits an elliptical shape; white internal coloring; green external coloring; no external sculpturing. The specimen measures between 0 - 60 mm in length and was assessed to be recently dead when collected.
Date: unknown
Partner: Elm Fork Natural Heritage Museum

Truncilla macrodon, Specimen #1463

Description: One preserved mussel specimen including both the left and right valves. The specimen exhibits an elliptical shape; white internal coloring; tan external coloring; no external sculpturing. The specimen measures between 0 - 60 mm in length and was assessed to be recently dead when collected.
Date: unknown
Partner: Elm Fork Natural Heritage Museum

Truncilla macrodon, Specimen #1439

Description: One preserved mussel specimen including both the left and right valves. The specimen exhibits an elliptical shape; white internal coloring; tan external coloring; no external sculpturing. The specimen measures between 0 - 60 mm in length and was assessed to be relatively-recently dead when collected.
Date: August 9, 1891
Creator: Walker, J. B.
Partner: Elm Fork Natural Heritage Museum

Quadrula petrina, Specimen #1526

Description: One preserved mussel specimen including both the left and right valves. The specimen exhibits a round shape; white internal coloring; tan external coloring; no external sculpturing. The specimen measures between 60 - 100 mm in length and was assessed to be relatively-recently dead when collected.
Date: unknown
Creator: Singley, J. A.
Partner: Elm Fork Natural Heritage Museum

Quadrula petrina, Specimen #989

Description: One preserved mussel specimen including both the left and right valves. The specimen exhibits an elliptical shape; moderately thick shell; white internal coloring; tan external coloring; no external sculpturing. Collected in the Colorado basin. The specimen measures between 100 - 120 mm in length and was assessed to be long dead when collected.
Date: August 15, 1979
Creator: Britton, Joseph & Britton, David
Partner: Elm Fork Natural Heritage Museum

Quadrula petrina, Specimen #990

Description: One preserved mussel specimen including both the left and right valves. The specimen exhibits an elliptical shape; moderately thick shell; white internal coloring; tan external coloring; no external sculpturing. Collected in the Colorado basin. The specimen measures between 100 - 120 mm in length and was assessed to be long dead when collected.
Date: August 16, 1979
Creator: Britton, Joseph & Britton, David
Partner: Elm Fork Natural Heritage Museum

Quadrula petrina, Specimen #991

Description: One preserved mussel specimen including both the left and right valves. The specimen exhibits an elliptical shape; moderately thick shell; white internal coloring; tan external coloring; no external sculpturing. Collected in the Colorado basin. The specimen measures between 100 - 120 mm in length and was assessed to be very-long dead when collected.
Date: August 17, 1979
Creator: Britton, Joseph & Britton, David
Partner: Elm Fork Natural Heritage Museum

Quadrula petrina, Specimen #992

Description: One preserved mussel specimen including both the left and right valves. The specimen exhibits an elliptical shape; moderately thick shell; white internal coloring; tan external coloring; no external sculpturing. Collected in the Colorado basin. The specimen measures between 100 - 120 mm in length and was assessed to be long dead when collected.
Date: August 18, 1979
Creator: Britton, Joseph & Britton, David
Partner: Elm Fork Natural Heritage Museum

Quadrula petrina, Specimen #993

Description: One preserved mussel specimen including the left valve only. The specimen exhibits an elliptical shape; moderately thick shell; white internal coloring; tan external coloring; no external sculpturing. Collected in the Colorado basin. The specimen measures between 100 - 120 mm in length and was assessed to be long dead when collected.
Date: August 19, 1979
Creator: Britton, Joseph & Britton, David
Partner: Elm Fork Natural Heritage Museum

Potamilus purpuratus, Specimen #680

Description: One preserved mussel specimen including the right valve only. The specimen exhibits a rhomboidal shape; thick shell; pink internal coloring; dark brown external coloring; no external sculpturing. Collected in the Colorado basin. The specimen measures over 120 mm in length and was assessed to be relatively-recently dead when collected.
Date: August 15, 1979
Creator: Britton, Joseph
Partner: Elm Fork Natural Heritage Museum

Potamilus purpuratus, Specimen #681

Description: One preserved mussel specimen including both the left and right valves. The specimen exhibits a rhomboidal shape; thick shell; pink internal coloring; reddish-brown external coloring; no external sculpturing. Collected in the Colorado basin. The specimen measures over 120 mm in length and was assessed to be relatively-recently dead when collected.
Date: August 15, 1979
Creator: Britton, Joseph
Partner: Elm Fork Natural Heritage Museum

Potamilus purpuratus, Specimen #682

Description: One preserved mussel specimen including both the left and right valves. The specimen exhibits a rhomboidal shape; thick shell; pink internal coloring; reddish-brown external coloring; no external sculpturing. Collected in the Colorado basin. The specimen measures between 100 - 120 mm in length and was assessed to be relatively-recently dead when collected.
Date: August 15, 1979
Creator: Britton, Joseph
Partner: Elm Fork Natural Heritage Museum