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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Using artificial tracers to observe timing of runoff from different landscape units in a small headwater catchment

Bier, Anthony Friedrich 11 1900 (has links)
Four artificial tracers were applied to a small headwater catchment in south western British Columbia to study runoff generated from topographically distinct landscape units. The seven hectare catchment is located in the University of British Columbia Malcolm Knapp Research Forest at low elevation (190-280 masl). A weir, multiple tipping bucket rain gauges and several piezometers were used to collect hydrological data. Three separate landscape units were identified based on topography, soil properties and proximity to the stream. The units included an area of shallow slope and deep soil, a riparian area along the intermittent stream channel and an area of very shallow soil with bedrock outcrops on a steep slope. Tracers used included rhodamine-WT, uranine, sodium chloride and potassium bromide. A suite of ion selective and fluorometric probes were used along with automated water sampling to monitor tracer breakthrough. The collected samples were analysed in the lab to validate the field measurements. Tracers were dissolved in solution and applied aerially with a backpack sprayer at the onset of forecasted precipitation events to facilitate rapid infiltration into the soil. The first application took place January 4th, 2006. Measurements were then taken continuously until March 20th, 2006, when a second round of tracers was applied to the landscape units. During the first measurement period, 532 mm of precipitation fell below the forest canopy over 75 days. During the second 78 day measurement period, 290 mm of rain fell. It was found that the overall wetness of the catchment affected travel times significantly. Large storms during the first, significantly wetter, application period exhibited similar lag times from peak event discharge to tracer arrival between the different landscape units. During small precipitation events and under dryer conditions, travel times were greatest in the area of shallow slope and deep soils. These lag times are indicative of longer pathways and perhaps the non-initiation of preferential flow below certain thresholds. In general, it was concluded that delineating catchments into groups of similar landscape units based on physical characteristics may be a promising new approach to explaining catchment runoff response.
42

Synthesis of the water budget on a semiarid watershed

Saplaco, Severo Rombaoa, January 1977 (has links) (PDF)
Thesis (Ph. D. - School of Renewable Natural Resources)--University of Arizona. / Includes bibliographical references.
43

A possible legal response to developed water in Arizona

Meitl, Joan M. January 1984 (has links) (PDF)
Thesis (M.S. - Watershed Management)--University of Arizona, 1984. / Includes bibliographical references (leaves 100-105).
44

Simulation and evaluation of water yield response to vegetation management on a forested watershed in Arizona

Hekman, Louis Harry, January 1977 (has links) (PDF)
Thesis (Ph. D. - Renewable Natural Resources)--University of Arizona. / Includes bibliographical references.
45

Shrub transplantation for watershed management and range improvement in Iran

Nemati, Nasser, January 1974 (has links) (PDF)
Thesis (M.S. - Watershed Management)--University of Arizona. / Includes bibliographical references.
46

Streamflow generation for the Senegal River basin

N'Diaye, Abdoulaye. January 1985 (has links) (PDF)
Thesis (M.S. - Hydrology and Water Resources)--University of Arizona, 1985. / Includes bibliographical references (leaves 224-227).
47

Procedures for developing a model for planning water-based linear parks along stream channels in semiarid urban regions

Johnson, Robert Chester, January 1973 (has links) (PDF)
Thesis (M.S. - Watershed Management)--University of Arizona. / Includes bibliographical references.
48

Development of a water conservation strategy for Al Qasseem Province, Saudi Arabia.

Shoaibi, Abdullah Mohammed al- , January 1990 (has links) (PDF)
Thesis (M. S. - Renewable Natural Resources)--University of Arizona, 1990. / Includes bibliographical references (leaves 61-62).
49

Natural Regeneration of Oak Woodlands in Southeastern Arizona

Borelli, Simone, January 1990 (has links) (PDF)
Thesis (M. S. - Renewable Natural Resources)--University of Arizona, 1990. / Includes bibliographical references (leaves 52-54).
50

Analysis of the quasi-steady state approximation on parameter identifiability for a dynamic soil erosion model.

Hernandez-Narvaez, Mariano, January 1992 (has links) (PDF)
Thesis (Ph. D. - Renewable Natural Resources)--University of Arizona, 1992. / Includes bibliographical references (leaves 194-202).

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