The Entrada Virtual Laboratory and Data Stream Network

Index

Entrada Field Station Mission Statement

Located on the Dolores River in the magnificent red-rock country of southeastern Utah, the Entrada Field Station provides opportunities for field-based interdisciplinary studies that emphasize ecology and the environment in the broadest sense. The facilities at Entrada are available for scholarly and educational activities ranging from writers- and artists-in-residence programs to ecological and hydrological sciences. At the Entrada Field Station, we emphasize research, education, and outreach on Colorado Plateau ecosystems and on the upper Colorado River Basin. Three broad and overlapping themes describe our foci: At Entrada, research, education, and outreach work synergistically to ensure a sound understanding of water and its connectivity across ecosystems, dynamics within watersheds, and its role in sustaining human activities. The Dolores River is a key tributary to the upper Colorado River Basin. Studies at the Entrada provide critical information for land managers, policy makers, and stakeholders on water quality and quantity in the upper Colorado River Basin and on how ecosystems will respond to future land-use and climate changes.

The Entrada Virtual Laboratory (EVL) is a cutting edge data stream tool to support field based interdisciplinary studies and research. The EVL brings real time data collected from multiple sensor networks located at the Entrada Field Station into a user-friendly graphical format. The long-term data sets will enhance our understanding of climate, ecology, hydrology, among many other natural processes. Use the data and tools on this site to teach science and research with data that is continually being updated. Teachers: Get involved, what tools would you like to see? Students: What discoveries can you make?

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Contact information

For questions or comments regarding the Entrada Virtual Laboratory, please contact
Sylvia Torti, Entrada Station Manager, 801.585.9474, , or
Kevin Hultine, Entrada Staff Scientist, 801.581.3545,


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Station Map


Click here to view larger map (opens in a new page)

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Explanation of stations

Weather Station 1

(Coordinates: 38º 47’ 50.59”N 109º 11’ 39.99”W 1278 m)
Description: Weather Station 1 is located on the scenic Dolores River near the USGS stream gauge:
USGS stream gage data.
The station collects data continuously every 20 minutes and has been in operation since July of 2006.

Measurements include:
  1. Air temperature and humidity: Vaisala HMP50 air temperature and RH probe (Vaisala Woburn, MA)
  2. Barometric pressure: Vaisala CS
    3. 105 PTB 110 Barometer (Vaisala, Woburn, MA)
  3. Precipitation: Texas Electronics, TE525-25 Tipping bucket rain gauge (Texas Electronics, Dallas, TX)
  4. Wind speed
    5. and direction: RM Young 05103-L Wind Monitor (RM Young Co., Traverse City, MI)
  5. Solar radiation: Apogee CS300 PYR-P Pyronometer (Apogee Instruments Inc., Logan, UT)
  6. Soil temperature: A3537 Type T Thermocouple wire, Campbell Scientific, Logan, UT)
Contact information:
For questions or comments regarding measurements or data, please contact Kevin Hultine, Entrada Staff Scientist, 801.581.3545,

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Weather Station 2

(Coordinates: 38º 47” 16.22”N 109º 11’ 34.62”W 1292 m)
Description: Weather Station 2 is located just above the mouth of Line Canyon, the largest of three box canyons that feed into the Dolores River Valley at the Entrada Ranch. The station collects data continuously every 20 minutes and has been in operation since July of 2006.

Measurements include:
  1. Air temperature and humidity: Vaisala HMP50 air temperature and RH probe (Vaisala Woburn, MA)
  2. Precipitation: Texas Electronics, TE525-25 Tipping bucket rain gauge (Texas Electronics, Dallas, TX)
  3. Wind speed
    4. and direction: RM Young 05103-L Wind Monitor (RM Young Co., Traverse City, MI)
  4. Soil temperature: A3537 Type T Thermocouple wire, Campbell Scientific, Logan, UT)
Contact information:
For questions or comments regarding measurements or data, please contact Kevin Hultine, Entrada Staff Scientist, 801.581.3545,

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Gauge Sap Flux Station

(Coordinates: 38º 47’ 47.08”N 109º 11’ 52.11”W 1279 m)
Description: The Gauge sap flux station is in a stand of tamarisk trees that were established during massive flooding events in the late 1950’s. The stand is dominated by tamarisk intermixed with native sagebrush, rabbit brush, coyote willow and Fremont cottonwood trees. We are currently measuring stem sap flux on 19 tamarisk trees, and four Fremont cottonwood trees using heat dissipation sensors (See below for theory).

Data from Gauge Sap Flux Station is currently available through Fall 2008. Live data is scheduled to be added in late 2009.


Other measurements include:

  1. Air temperature and humidity: Vaisala HMP50 air temperature and RH probe (Vaisala Woburn, MA)
  2. Precipitation: Texas Electronics, TE525-25 Tipping bucket rain gauge (Texas Electronics, Dallas, TX)
  3. Volumetric soil moisture at 10, 20, 40, and 60 cm depths under the canopy: Sentek WCq EnviroSMART soil moisture probes (Sentek PTY, Adelaide, Australia)
  4. Groundwater height and temperature at two locations: In Situ Level-Troll 500, In Situ, Inc., Ft Collins, CO)
Contact information:
For questions or comments regarding measurements or data, please contact Kevin Hultine, Entrada Staff Scientist, 801.581.3545,

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Orchard Sap Flux Station

(Coordinates: 38º 47’ 53.56”N 109º 12’ 15.50”W 1277 m)
Description: The Orchard sap flux station is located in a highly productive and dense stand of tamarisk trees. Establishment of tamarisk likely occurred here in the late 1950’s during intense flooding. However, a fire rolled through the stand in the mid 1980’s, and most of the trees are therefore younger than most stands at the Entrada Ranch. We are currently measuring stem sap flux on 20 tamarisk trees using heat dissipation sensors (See below for theory).

Data from Orchard Sap Flux Station is currently available through Fall 2008. Live data is scheduled to be added in late 2009.


Other measurements include:

  1. Air temperature and humidity: Vaisala HMP50 air temperature and RH probe (Vaisala Woburn, MA)
  2. Volumetric soil moisture at 10, 20, 40, and 60 cm depths under the canopy: Sentek WCq EnviroSMART soil moisture probes (Sentek PTY, Adelaide, Australia)
  3. Groundwater height and temperature at two locations: In Situ Level-Troll 500, In Situ, Inc., Ft Collins, CO)
Contact information:
For questions or comments regarding measurements or data, please contact Kevin Hultine, Entrada Staff Scientist, 801.581.3545,

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Theory: Heat dissipation (Granier) sap flux theory and measurement

Granier-type sap flow sensors (Granier 1987, Hultine et al. 2007) consist of a paired heated and unheated sensor 10 or 20 mm in length inserted radially into the xylem of a tree (Figure 1). The temperature difference between the heated and unheated sensor is empirically related to sap flow with a relationship determined by lab calibration with the equation:
(1)

where DT0  is the temperature difference between the heated and unheated probes, DT0  is the temperature difference obtained under zero flow conditions (usually at night when atmospheric vapor pressure is at or near zero), and coefficients a and b are fitting parameters.


Figure 1 – Heat dissipation sap flow probes installed in a tamarisk tree at the Entrada.

References:
Granier, A. 1987. Evaluation of transpiration in a Douglas fir stand by means of sap flow Measurements. Tree Physiology 3:309-320

Hultine, K.R., S.E. Bush, A.G. West, and J.R. Ehleringer. 2007. The effect of gender on sapflux-scaled transpiration in a dominant riparian tree species: box elder (Acer negundo). Journal of Geophysical Research 112 G03S06, DOI 10.1029/2006JG000232

Contact information:
For questions or comments regarding measurements or data, please contact Kevin Hultine, Entrada Staff Scientist, 801.581.3545,

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Data Disclaimer:

Real time data provided by this web site -- including temperature and humidity, barometric pressure, solar radiation, precipitation, and soil temperature are preliminary and have received little or no review. Information concerning the accuracy and appropriate uses of these data or concerning other environmental data may be obtained from the staff scientist.

All sap flow data, soil moisture data and groundwater data are for educational purposes only and may not be used for publication without prior permission from the staff scientist and the University of Utah.

For more information regarding the appropriate uses of these data, please contact Kevin Hultine, Entrada Staff Scientist, 801.581.3545,