Plant Physiology
Measurement Instrumentation for Plant Physiology
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Campbell Scientific measurement systems are used extensively by agronomists, crop scientists, and plant physiologists in field- and laboratory-based plant physiology research applications. Our measurement systems feature reliability, accuracy, and the flexibility to measure nearly any parameter. Typical systems include greenhouse monitoring/control applications, weather/evapotranspiration stations, CO2 and water vapor flux measurement systems, and systems for monitoring soil parameters.
Plant Physiology System Benefits
Bowen ratio, eddy covariance, TDLAS, and automated weather stations are standard products; greenhouse and growth chamber instrumentation systems can be configured to user specifications.
- Fluxes can be computed in real time, or the raw data archived for later analysis.
- Open format allows data to be input into third-party software.
- Most sensors can be measured.
- Field-based systems operate reliably in harsh environments.
- Long-term operation is provided by batteries and solar panels or ac power.
- Several reliable data telemetry options are available.
- Systems provide on-board statistical and mathematical capabilities.
- Stations are easily expandable—add new sites or add sensors to existing stations or systems.
- Powerful PC software supports programming, data retrieval, and data display; software collects and processes time-series data.
Greenhouse and Growth Chamber Measurements
Our systems can be configured to provide accurate, stand-alone monitoring of greenhouse or growth chamber conditions for use in agricultural and plant physiology research applications. Programmable dataloggers allow multiple options for system configuration, measurement and output intervals, and data retrieval. A variety of sensors can be used including: solar radiation, temperature (air, water, soil), relative humidity, dew point, leaf wetness, and barometric pressure. Data are typically viewed and stored in the units of your choice. In addition, the system can easily be configured to monitor electrical power or water usage to provide data on consumption. The system can also be programmed to sound audible alerts or call out via voice synthesized modem if alarm-level conditions are reached.
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 dataloggers allow multiple options for station configuration, measurement and output intervals, and data retrieval. Almost any meteorological sensor can be used including: wind speed and direction, solar radiation, temperature (air, water, soil), 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 datalogger 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 analyzer. Measurements of other trace gas fluxes, such as N2O and CH4, are obtained with our TGA100 tunable diode laser analyzer.
Soil Measurements
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 water content and 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, multipoint (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.
Plant Physiology System Components
Dataloggers used in Plant Physiology
All of our measurement systems are based around programmable dataloggers that measure the sensors, then process or store the data. We designed our dataloggers 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 dataloggers can also control external devices, such as valves and samplers.
Sensors used in Plant Physiology
Most sensors, even those made by other manufacturers, interface directly to our dataloggers. Sensors used in our agricultural research (micromet) systems include sonic anemometers, hygrometers, fine wire thermocouples, and open and closed path gas analyzers, including the LI7500 Open-Path CO2/H2O Analyzer.
Data Retrieval
We offer multiple communications options for data retrieval; options can be mixed within the same network. Telecommunications options include telephone (landline, voice-synthesized, cellular), radio, multidrop, short-haul, and satellite. On-site options include storage module, PDA, displays, and laptop computer.
