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Setting & Research

Dynamic Map

Data

Photos

• Setting & Research

  This site is part of an elevational transect that increases in altitude from west to east.

  Sites include San Joaquin Experimental Range, Soaproot Saddle, Providence Creek Headwater Catchments, and Short Hair, spanning a 2300-m elevation range that captures gradients in climate, regolith, soils, and vegetation. Along this transect, bedrock lithology is generally constant (intrusive felsic plutons). Ecosystems range from low-elevation oak savannah (rain-dominated) to high-elevation subalpine forest (snow-dominated). A series of eddy-covariance gas flux towers are installed at these sites (see below). Examples of transect-length work include soil and regolith depth, chemistry, and moisture characterizations; vegetation surveys; forest water-balance research; and wind-blown dust geochemistry and microbiology studies.

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  Climate, Landscape, Vegetation, Soils

  From O'Geen et al., 2018:

  The subalpine forest site Short Hair is the highest-elevation site in the elevational transect, and represents a headwater catchment situated along Short Hair Creek. Mean Annual Temperature: 4.2°C. Mean Annual Precipitation: 1078 mm yr⁻¹.

  This site was glaciated in the Pleistocene resulting in hard weathered bedrock (WB) underlying soil (Gillespie and Zehfuss, 2004).

  The Short Hair site has a cryic soil temperature regime and udic soil moisture regime. The site has thin patchy and rocky soils that limit moisture storage intermixed with areas of deep glacial till. Soils are mapped as the Stecum series (sandy-skeletal mixed Typic Cryorthents).

  Vegetation community is mostly lodgepole pine (Pinus contorta Douglas ex Loudon) and western white pine (Pinus monticola Douglas ex D. Don).

  For additional information on climate and vegetation, see also Goulden et al., 2012.

  

  Panorama of Short Hair Creek tower site. July 2014. Photo by Erin Stacy.

  A full size image is available at the Sierra Nevada / San Joaquin Hydrologic Observatory digital library (external link).

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  Flux Tower

  An eddy-covariance flux tower was installed at this site in October 2009. Due to harsh winter conditions and a falling tree, the flux tower was down from 2011-2014. A replacement tower was brought in by helicopter and raised by a team in August 2014. Instruments were reinstalled June 2015. Elevation of the tower is 2700 m above sea level.

  The flux tower is used to analyze the carbon and water balance of the surrounding forest. Instruments on the flux tower track changes in carbon dioxide, water vapor, air temperature, relative humidity, and other atmospheric properties.

  Hydrological monitoring infrastructure is located within the footprint of the eddy flux tower.

  Panorama of Short Hair Creek tower site. July 2014. Photo by Erin Stacy.

  A full size image is available at the Sierra Nevada / San Joaquin Hydrologic Observatory digital library (external link).

• Dynamic Map

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• Data

  Flux Tower Transect, Short Hair Creek - Flux Tower, Meteorology (2009-2018)
  12 components  •   Short Hair (2670 m elevation)  •   Climatology / Meteorology, Biology / Ecology  •   Mike Goulden; Anne Kelly

  National - Flux Tower - AmeriFlux Network data (2007-2018)
  14 components  •   Boulder Creek Watershed, Jemez River Basin, Reynolds Creek Experimental Watershed, Susquehanna Shale Hills Critical Zone Observatory, San Joaquin Experimental Range (210-520 m elevation), Soaproot Saddle (1000-1500 m elevation), Short Hair (2670 m elevation)  •   Climatology / Meteorology  •   Boulder Creek Critical Zone Observatory; Catalina-Jemez Critical Zone Observatory; Reynolds Creek Critical Zone Observatory; Shale Hills Critical Zone Observatory; Southern Sierra Critical Zone Observatory

• Photos

  SSCZO - Flux Towers

  

  At the San Joaquin Experimental Range (SJER), the SSCZO flux tower sits on a small rise in the oak-pine woodland. This is the lowest site of the flux-tower transect, with the tower installed at 405 m in elevation.  

  

  Fully erected, the SJER tower stands about 29 m tall (~95 ft). 

  

  However, the tower also telescopes down for maintenance. 

  

  Erin Stacy (UC Merced) exchanges the filters on the gas intake. 

  

  The flux tower at Soaproot Saddle stands in a small forest clearing. The tower, approximately 39 m tall (125-130 ft), is surrounded by a mix of Ponderosa pine and oak. Here the WyCEHG (Wyoming) sets out equipment to conduct geophysical surveys in the tower footprint. 

  

  Defensive measures were taken for the Soaproot Saddle tower in advance of a prescribed burn. The Clarence Burn burned up to a nearby firebreak in January 2014, but did not burn the area immediately around the tower 

  

  Matt Meadows (Field Manager, UC Merced) begins the climb for routine tower maintenance in a late January storm, 2014. 

  

  Pete Hartsough (collaborator, UC Davis) stands next to the Soaproot tower, September 2013, with core tubes in hand. A large drilling unit cored soil and saprolite to a depth of ~4 m on most attempts at this site. 

  

  The P301 tower is the tallest of the four towers at 50 m (160 ft), plus a lightning rod. It stands near the top of the Providence catchments at 2015 m in elevation. 

  

  The P301 tower near the end of the 2014 winter. 

  

  Matt Meadows (Field Manager, UC Merced) shows off the filter intakes at the top of the P301 tower. 

  An eddy covariance flux tower is located near the top of the P301 watershed. Instruments collect data on temperature, relative humidity, and fluxes of carbon dioxide and water vapor to determine the physiological responses of the site (for example, how photosynthesis increases with light) and summed over a year to determine the carbon balance of a site (how much carbon it is gaining or losing). Three other flux towers have been instrumented at different elevations with the Sierras including the San Joaquin River, Soaproot, and Short Hair Creek.

  This west-east transect spans elevation gradient from 400 m to 2700 m. The change in elevation is accompanied by a slight increase in precipitation, but the main change is a shift from rain-dominated precipitation to snow-dominated precipitation. The climatic shift plays out in other ways as well. At lower elevations, high temperatures and low water availability limit evapotranspiration by vegetation. Meanwhile, forest activity (evapotranspiration) at higher elevations is limited by cold winter temperatures. There is a sweet spot at middle elevations of yera-round evapotranspiration and forest activity.

  Photo galleries of each flux tower are available: San Joaquin Experimental Range;  Soaproot Saddle; Providence subcatchment P301; and Short Hair Creek.

  SSCZO - Instruments

  

  Matt Meadows (Field Manager, UC Merced) checks on an instrument on the P301 flux tower.

  

  Anemometer measuring wind speed and direction.

  

  Ultrasonic anemometer on the P301 flux tower measures wind speed and direction in 3 dimensions. Data is connected to gas samples taken every quarter second at the filters on the left (beige circles). 

  

  Instrument cluster featuring a relative humidity sensor, ultrasonic snow depth sensor, co-located soil moisture and temperature sensors at different depths, and a solar panel to power it all. 

  

  Instrument cluster at  the P303 Upper Met site with ultrasonic snow depth sensor and co-located soil moisture and temperature sensors. 

  

  Instrument cluster at  the P300 Lower Met site with ultrasonic snow depth sensor and co-located soil moisture and temperature sensors. The pole also psupports a solar panel, and an enclosure with a backup power supply and the data logger.

  

  Instruments installed in the P301 meadows include wells and piezometers, at different locations to assess surface and groundwater flows. 

  

  Several clusters of instruments measure the water balance. These clusters each contain soil moisture and temperature sensors, an air temperature sensor, relative humidity sensor, and an ultrasonic snow depth sensor. 

  

  These water balance instruments are clustered at two different elevations, with north, flat, and south facing aspects. Conditions are measured under canopy, at drip edge, and at open canopy. Water balance measurements are also made in the wireless sensor network that stretches along the P301 meadow. 

  

  The eight subcatchments and two integrating catchments in the KREW project have flumes to measures discharge. 

  

  The large KREW flumes are complemented by small flumes for low flow. 

  

  Each of those eight KREW subcatchments also has a plastic-lined settling basin to capture sediment. 

  

  There are two meteorological stations in the Providence catchment - one at the lower elevation range and one near the crest. Each meteorological station has a rain gauge. 

  

  At the upper meteorological station, there is a snow pillow. This snow pillow tracks the weight of snow above it. Combined with the snow depth measurements, the two permit the calculation of amount of water in the snow pack.

  

  Another view of the snow pillow. 

  Hundreds of instruments and sensors have been deployed in the primary SSCZO research site of the Providence Creek watershed as well as in Wolverton basin.  Additional SSCZO flux towers and instruments have also been installed at the San Joaquin Experimental Range, Soaproot Saddle, and Short Hair Creek.

  Explore more photos of the intstuments and sensors used by SSCZO.

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Geology

• Geology

  Short Hair Creek, 2700 m elevation
  Quad: Blackcap Mountain

  This site was glaciated in the Pleistocene (Gillespie and Zehfuss 2004) and is situated on glacial till. The bedrock immediately below the tower is of unknown composition. However, two different bedrock units are exposed within 500 m of the tower (Bateman 1965).
   

  Aplite and felsic quartz monzonite dikes (Kap)
  Dinkey Creek Granodiorite (Kdc, formerly Granodiorite of Dinkey Creek, same as P301)
  “Medium-grained, generally strongly foliated. Contains abundant disc-shaped mafic inclusions and mafic clots composed of hornblende, biotite, sphene, plagioclase, and opaque minerals. Intrudes the quartz diorite of Blue Canyon. Age by Rb-Sr whole-rock isochron 110 +/- 11 m.y.” (Bateman and Wones 1972). The mafic inclusions are “as much as 30 cm long and 5 cm thick. The mafic minerals are intergrown, and individual grains are anhedral” (Bateman 1992).

  SJER, 400 m elevation
  Quad: Millerton Lake
  Ward Mountain Trondhjemite (Kw) (formerly Leucotonalite of Ward Mountain)

  Soaproot Saddle, 1100 m elevation
  Quad: Shaver Lake
  Bass Lake Tonalite (Kbl, formerly Tonalite of Blue Canyon)

  P301, 2000 m elevation
  Quad: Huntington Lake
  Dinkey Creek Granodiorite (Kdc, formerly Granodiorite of Dinkey Creek)