Specifications 12905B24Q0259.pdf

USDA Agricultural Research Service Soil and Water Conservation Research 48037 Tubbs Ranch Rd. Adams, Oregon 97810

Minimum Acceptable Specifications for Eddy Covariance Flux System with Energy Balance

Mission-critical requirements

Gas analyzer and anemometer: integrated open-path gas analyzer and 3D sonic anemometer with ability to assess water vapor and carbon dioxide fluxes; operating temperature of -30 to 50 degree C, includes minimum warranty of 3 years or 17,500 operation hours; gas analyzer precision: 0.2 mg m-3 for carbon dioxide and 0.004 g m3 for water vapor; sonic anemometer precision: 1 mm s-1 horizontal windspeed and 0.5 mm s-

1 for vertical windspeed

Net radiometer: net radiometer with internal temperature monitoring and frost melting capabilities; spectral range of pyranometer: 305-2800 nm; spectral range of pyrgeometer: 4500-50,000 nm; sensitivity: 10-40 μV W-1 m2

Soil flux plates (3 plates total): sensitivity: 50 μV W-1 m-2, compatible with CR1000X data logger or similar;

minimum cable length of 57’

Temperature, relative humidity sensor: pre-calibrated digital sensor capable of on-site calibration, SDI-12 output; air temperature range of -40 to 70 degrees C with minimum accuracy of 0.2 degrees C, accuracy of 2% relative humidity across full range

Data logger: CR1000X or equivalent, minimum 3 yr warranty, includes programming and calibration for data analyses and integration, included card drive to expand memory, include web page for direct connection with web browser; must be compatible with all other equipment in the system; keyboard display; must be compatible with all software and fully integrated with the system

Analog expansion tool: minimum of 16 differential or 32 single-ended input channels to expand data collection, must be programmable and compatible with the data logger and all other equipment in the system

PAR sensor: spectral range of 389 to 692 nm, pre-calibrated, four year warranty, self-powered, 180 degree field of view, spectral sensitivity of 5 nm; sensitivity: 0.01 mV per µmol m-2 s-1

Rain gauge: minimum 0.1 mm accuracy, 12’ cable

Soil moisture and temperature sensor: 12 cm rods, SDI-12 signal, volumetric soil water content measurements across wide range of soils, measure of dielectric permittivity, bulk electrical conductivity, and soil temperature; operating temperature of -50 to 70 degrees C;

accuracy if 1%, depending on EC, and soil temperature within 0.02 degrees C;

57’ cable; include rod guide tool for installation

Solar panel and power supply: 370 W solar panel with 57’ cable; 84aH power supply that fits into the enclosure, pre-wired connections and is compatible with the data logger and all other equipment in the package

Additional equipment: 64’ 22 AWG cable with drain, 64’ 2-conductor 16AWG power cable, 4’ 2-conductor 16AWG power cable, large solar radiation shield, sensor crossarm, mounting kits, three 15’ tripods with crossarms and guy kits, weather-resistant enclosure (minimum of 14X16”) with mounting kit and cable conduits, minimum of 4 desiccant bags, PVC pipe for cables, power distribution block, 2’ Cat6 cable connector, GPS receiver with integrated antenna and minimum 15’ cable, mounting stands for all equipment, totes for tripods, strain-relief bracket kit for enclosure; 16 GB microSD flash memory card; USB memory card reader with minimum 3’ cable; zero and span shroud kit for analyzer calibration with stand and mount

Software: programming integrated with data logger for data analysis, quality control, calibration, and retrieval; ability to create custom programs and displays, ability to output data as CSV and XML for external use, ability to communicate with laptop, able to retrieve data through telecommunication; custom data program for flux data retrieval and interpretation including QA/QC metrics