Campbell Scientific measurement systems are used extensively by agronomists, crop scientists, and soil scientists in agricultural research applications. Our measurement systems feature reliability, accuracy, and the flexibility to measure nearly any parameter. Typical systems include weather stations, evapotranspiration stations, CO2 and water vapor flux measurement systems, and systems for monitoring soil parameters.
Weather Stations and Evapotranspiration Stations
Our weather stations provide long-term, stand-alone monitoring of meteorological parameters for all types of agricultural research applications. Programmable data loggers allow multiple options for station configuration, measurement and output intervals, and data retrieval. Almost any meteorological sensor can be used including: wind speed, wind direction, solar radiation, air temperature, water temperature, soil temperature, relative humidity, dew point, precipitation, leaf wetness, and barometric pressure. Wind vector, vapor pressure, histogram, and sample on maxima or minima are standard in the data logger instruction sets. Data are typically viewed and stored in the units of your choice (e.g., wind speed in mph, m/s, knots).
Pre-programmed stations calculate potential evapotranspiration using the Penman-Monteith equation; other evapotranspiration algorithms can be entered if preferred.
Surface Flux Measurements
Our flux systems can measure atmospheric gradients or vertical turbulent transport directly. Standard systems that support either aerodynamic or Bowen ratio gradient techniques are available for measuring heat, water vapor, and CO2 fluxes. Our standard eddy covariance systems use a three-dimensional sonic anemometer and either an open-path krypton hygrometer or LI-COR's open-path H2O and CO2 analyser. Measurements of other trace gas fluxes, such as N2O and CH4, are obtained with our TGA100 tunable diode laser analyser.
We can measure nearly every commercially available soil sensor, including tensiometers, heat flux plates, thermocouples, psychrometers, lysimeters, and gypsum blocks.
Our soil water instrumentation is used extensively to monitor soil water content and soil water matric potential. Our time-domain reflectometry (TDR) systems provide accurate, reliable measurements of soil volumetric water content and bulk electrical conductivity in soils over a wide range of textures and soluble salt concentrations. We offer both long-term, multi-point (up to 512 probes) systems and a portable system for instantaneous soil water content readings. Our sensors that measure soil water matric potential use heat dissipation and electrical resistance methods.
All of our measurement systems are based around programmable data loggers that measure the sensors, then process or store the data. We designed our data loggers to allow a high degree of flexibility. Measurement types, scan rates, and recording intervals are all programmable. On-board processing instruction sets contain programmed algorithms that process measurements and output results in the desired units of measure. Our data loggers can also control external devices, such as valves and samplers.
Most sensors, even those made by other manufacturers, interface directly to our data loggers. Sensors used in our agricultural research (micromet) systems include sonic anemometers, hygrometers, fine wire thermocouples, and open path gas analysers, and closed path gas analysers, including the CS7500 Open Path CO2/H2O Analyser (LI-COR's LI-7500).
We offer multiple communications options for data retrieval; options can be mixed within the same network. Telecommunications options include landline telephone, voice-synthesized telephone, cellular telephone, radio, multidrop, short-haul, and satellite. On-site options include storage module, PDA, and laptop computer.