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Soil Science

Products for Stand-alone Soil Monitoring

Campbell Scientific soil water instrumentation is used extensively to monitor water content and matric potential in applications requiring knowledge of soil water inventory or movement. Our soil water instrumentation can be used to automatically monitor multiple probes for time-series information or make point measurements using a portable, hand-held system. Proven reliability, durability, low power use, accurate measurements, and the ability to customize each system make our dataloggers and sensors ideal for a variety of applications including:

Agricultural research
Soil water content profiling
Irrigation scheduling
Slope stability
Leak detection
Greenhouse/horticultural
Forestry
Solute transport studies
Watershed studies

Soil Science System Benefits

Soil water sensors and systems use proven and innovative measurement methods.
Versatility is inherent in all systems allowing expansion and custom configuration.
System is compatible with other available sensors.
Dataloggers provide statistical and mathematical processing for on-site data management.
Battery/solar power system supports long-term, remote operation.
Our systems have proven reliability even in harsh environments.
Communications options include satellite, phone, cellphone, and radio.
Expert customer support ensures you get the correct measurement.

Dataloggers used in Soil Science

Our measurement systems are based around programmable dataloggers that measure the sensors, then process, store, and transmit the data. We offer a family of reliable battery-powered dataloggers that have wide operating temperature ranges and ample input channels for commonly used sensors. Our dataloggers interface directly to most sensors, eliminating external signal conditioning. If needed, channel capacity can be expanded using multiplexers.

Our dataloggers also feature programmable scan rates, measurement types, and recording intervals and provide onboard statistical and mathematical functions for on-site data management.

Sensors used in Soil Science Measurements

We can measure nearly every commercially available soil sensor, including tensiometers, heat flux plates, thermocouples, psychrometers, lysimeters, and gypsum blocks. See the 'Soil Moisture (Water Potential)' and 'Soil Moisture (Volumetric Water Content)' links above for more information about the quality sensors we manufacture.

Communications

The availability of multiple telecommunications and on-site options for retrieving data also allows systems to be customized to meet exact needs. Options include: voice-synthesized phone, telephone, cellphone, satellite, radio, ethernet, short haul, meteorburst, coaxial cable, and storage module. Systems can be programmed to send alarms or report site conditions by calling out to computers, phones, radios, or pagers. Real-time or historical data can be displayed or processed with Campbell Scientific software. Data can also be exported as ASCII files for further processing by spreadsheets, databases, or analysis programs.

Soil Water Content

We measure soil water content using methods that are sensitive to soil dielectric constant. Our TDR100-based system uses proven time-domain reflectometry (TDR) to accurately and reliably measure soil volumetric water content and bulk electrical conductivity in soils over a wide range of textures and soluble salt concentrations. This system uses coaxial multiplexers to connect the TDR100 to up to 512 TDR probes. The TDR100 features lower current demand and a typical measurement time of two seconds. The operating temperature range of -25° to +50°C covers typical applications as well as monitoring frost depth. Windows support software provides setup, troubleshooting, and display of waveforms and measurements. A customized 16" x 18" environmental enclosure is configured to easily mount and protect a CR1000 datalogger or CR3000 datalogger, 12 volt power supply, TDR100, and 8-channel multiplexer.

The CS616-L is a self-contained water content sensor that uses high-speed electronics in the body of the sensor to generate a square wave output with a period that is proportional to water content. Measurement of the square wave by a datalogger's single-ended channel gives precise, high-resolution water content measurements in less than 0.1 seconds, even with long cables.

For portable volumetric water content measurements, the hand-held HydroSense® consists of a probe and output display. It can be easily carried from site to site and provides immediate soil water content readings. Low power requirements and fast measurement times provide thousands of measurements, powered only by 2 AA batteries.

Soil Water Matric Potential

Sensors from Campbell Scientific that measure soil water matric potential use heat dissipation and electrical resistance methods. The 229-L Matric Potential Sensor covers a water potential range from -10 J/kg to -104 J/kg by using the temperature response of a heating element embedded in a ceramic matrix. A constant current source is available for reliable and precise heating. Sixteen 229-L sensors are easily multiplexed to a single datalogger differential input channel using the AM16/32 multiplexer. Watermark and Delmhorst electrical resistance sensors provide an inexpensive method of measuring smaller matric potential ranges.

Questions? Please refer to the email address in this graphic if the adjacent link does not work.