Using Electrical Conductivity (EC) Sensors in Precision Agriculture

The measurement of soil EC is widely used in agriculture. However, there is still confusion around the meaning of the readings and their application in precision agriculture.

To what extent can EC sensors be used for ‘precision fertilization management’? In fact, ‘Soil EC’ may refer to different types, or methods, of EC readings, each with its own significance.This article will explore the meaning of the different EC measurements and evaluate their applicability for precision agriculture.

The electrical conductivity is the ability of a material to transmit electrical current. The question is, therefore, which medium is being measured and how can the reading be interpreted and used? The most commonly used EC measurement in precision agriculture is the soil bulk EC, or soil apparent EC (ECa). This soil EC correlates with various soil properties, such as soil texture and water holding capacity. Sandy soils will have a lower EC reading than clay soils.

Mapping the ECa within a field provides additional information on the soil variability within that field and on year-to-year trends, such as salinization and compaction of the soil. Such information can aid in deciding on variable rates of herbicides and nitrogen fertilizer, as their application efficiency depend on soil texture. For instance, a split application of nitrogen may be required in light-textured soils.

If correlated with yield maps, ECa can also give an idea on the nitrogen rate to apply, although such correlation does not always exist, and many additional agronomical considerations must be taken into consideration. ECa is, therefore, one more tool that can be used to better understand soil variability in the field. However, it cannot replace traditional soil testing.

Other methods to evaluate electrical conductivity of soil focus on measuring the EC of the soil-solution, hence its salinity. The difference between these methods is mainly the moisture state of the soil. The electrical conductivity of the soil-solution changes continuously, depending on the moisture content of the soil. Therefore, for standardization, all EC measurements must be taken at the same moisture content.

The most acceptable moisture content is the moisture of ‘saturated paste’, also referred to as ‘EC of the saturated paste extract’. Most references in the literature, such as tolerance to salinity of different crops, relate to the EC of the saturated extract, denoted as ECe. ECe gives an indication of the soil salt content. It can be used to estimate whether there is excess of salts in the soil. However, it does not imply exactly which salts and nutrients are present. Unlike the apparent electrical conductivity of the soil, ECe cannot be measured directly in the field using sensors, and it must be measured at the laboratory. There are, though, mathematical models that attempt to correlate between ECa and ECe.

To summarize, EC sensors in precision agriculture are a valuable tool for better understanding variability and trends in the soil. This is especially true for soil EC mapping and to a much lesser extent to stationary single soil sensors. However, precise fertilization management is a complex process, that takes into consideration multiple variables and parameters, well beyong beyond EC alone.

Leave a Reply

2 comments on “Using Electrical Conductivity (EC) Sensors in Precision Agriculture

  1. Absolutely agree I have seen many farmers who have been put off VRA because of the poor results they have had with EC mapping , and the way it was portrayed. There was never any ground truthing of what was driving the EC , either physical or chemical. Unfortunately there are still practitioners who espouse EC mapping as soil maps ,which they are not, however it is relatively inexpensive to produce , and pretty ambiguous with a lot of assumptions made that are rarely properly ground truthed. So there value is limited.

Sensors/IoT Stories
Farmer-Tablet
Data ManagementAgriculture’s Next Breakthrough: New Technologies Are Driving Efficiency, Data Insights
July 3, 2018
We live in an exciting time in agriculture. Not only is technology advancing rapidly, but the understanding and comprehension of Read More
JDandPessl
Sensors/IoTJohn Deere, Pessl Instruments Team Up to Create Opportunities
June 18, 2018
John Deere is best known for its line of tractors, combines, sprayers, and implements. However, in an effort to help Read More
Field-Equipment
Sensors/IoTTop 6 Digital Transformation Trends in Agriculture
May 15, 2018
In recent years, technology in agriculture, also known as AgTech has rapidly changed the industry, writes Daniel Newman on Forbes.com. Read More
Industry NewsCropX Announces New Soil Intelligence Platform Powered by Deep Sensor
May 1, 2018
The agricultural industry is in the midst of a smart farming evolution, and the Internet of Things (IoT) era has Read More
Trending Articles
ISPA-Yoshua-Bengio
EventsHighlights from the 14th International Conference on Precision Agriculture
July 9, 2018
The 14th International Conference on Precision Agriculture (ICPA) presented by the International Society of Precision Agriculture (ISPA) was held in Montreal, Read More
Topcon X30 Console in cab
EventsAssociation Seeks Definitive Definition of “Precision Agriculture” — What’s Your Vote?
July 2, 2018
More than two-dozen definitions of precision agriculture have been identified through the years — but which is the best and Read More
AmericasRaven Name to Grace New South Dakota State University Facility
June 27, 2018
According to a press release issued by the company, Raven Industries was recognized today in the naming of South Dakota Read More
dropcopter
DronesNew York Apple Orchard Claims World First in Pollination by Drone
June 18, 2018
Beak & Skiff Apple Orchard in LaFayette, NY, is the first orchard in the world to use drones to pollinate Read More
JDandPessl
Sensors/IoTJohn Deere, Pessl Instruments Team Up to Create Opportunities
June 18, 2018
John Deere is best known for its line of tractors, combines, sprayers, and implements. However, in an effort to help Read More
Matt-Waits-featured
Decision Support SoftwareSST’s Matt Waits: Innovative Data Solutions Key to Transforming Global Agriculture
May 31, 2018
Proagrica, part of RELX Group, earlier this year acquired U.S.-based precision agriculture solutions company, SST Software, in a move set Read More
Latest News
Industry NewsFarmobile Acquires Prime Meridian, Taps Cubbage as New …
July 13, 2018
Farmobile today announced an agreement to acquire the assets of Prime Meridian, a precision agriculture data management company based in Read More
group-photo
DronesPrecision Agriculture Takes Flight at North Carolina St…
July 13, 2018
Take a walk into the Suggs Laboratory for Precision Agriculture and Machine Systems and it’s hard not to be impressed, Read More
Skeketee-IC-Weeder
DronesAutomated Weeders Have Arrived in Vegetable Fields
July 12, 2018
The vegetable production areas of the Central Coast of California have lifted vegetable cultivation to a high art, writes Richard Read More
AgJunction, InfoAg 2014, Autosteer, GPS
Industry NewsAgJunction Settles with Raven in Patent Infringement Su…
July 12, 2018
AgJunction Inc., a leader in advanced guidance and autosteering, has settled a patent infringement lawsuit it filed against Raven Industries, Read More
Retailer-Grower-tablet
Business ManagementTaking Measure of the Precision Agriculture Program: 6 …
July 12, 2018
In the overall agriculture market, the rhetoric surrounding emerging technology over the past half-decade has been nothing short of breathless. Read More
raven-slingshot-job-generator-job-sync-1
Industry NewsNew Raven Slingshot Advancements Will Help Save Time, R…
July 11, 2018
Raven Industries, Inc. has announced several new services available on the Slingshot and Viper 4 platforms: Job Generator and Job Read More
Onsite-logo
Industry NewsAgIntegrated Acquires Exclusive Licence to Satshot’s Im…
July 11, 2018
AgIntegrated, Inc. (AGI), a leader in precision ag data integration and software development, and Satshot, a leader and pioneer in Read More
Australian Harvest
Australia/New ZealandAustralian Agritech Plants Blockchain for Efficiency
July 11, 2018
“Agritech” at one time would have meant new equipment such as tractors and combine harvesters, but today it refers to Read More
Tomato-crop-India
AsiaIndia: Using Artificial Intelligence for the Good of Fa…
July 11, 2018
After graduating from IIT-Madras, the first thing that Vivek Rajkumar did was to buy four acres near Thiruvananthapuram and start Read More
BrightFarms
Industry NewsForbes List of Innovative Ag-Tech Companies Includes Gr…
July 9, 2018
Forbes magazine recently posted a list of the 25 most innovative ag-tech startups in 2018, which includes a few companies Read More
AmericasNutrien Ag Solutions Brand, New Digital Platform Launch…
July 9, 2018
Nutrien (formerly Crop Production Services) has officially rebranded its retail business to Nutrien Ag Solutions, aligning the company’s retail operations Read More
ISPA-Yoshua-Bengio
EventsHighlights from the 14th International Conference on Pr…
July 9, 2018
The 14th International Conference on Precision Agriculture (ICPA) presented by the International Society of Precision Agriculture (ISPA) was held in Montreal, Read More
TerrAvion
Industry NewsTerrAvion Integrates Aerial Imagery with John Deere Ope…
July 6, 2018
TerrAvion, Inc., a large volume provider of aerial imagery to agriculture, has announced an integration to allow TerrAvion’s aerial imagery Read More
Farmer-Tablet
Data ManagementAgriculture’s Next Breakthrough: New Technologies…
July 3, 2018
We live in an exciting time in agriculture. Not only is technology advancing rapidly, but the understanding and comprehension of Read More
Nebraska-Storm
Precision IrrigationNotes from the Field: A Look at Irrigation Management P…
July 2, 2018
One of the things I love most about my work is making periodic treks into the field – more often Read More
Topcon X30 Console in cab
EventsAssociation Seeks Definitive Definition of “Preci…
July 2, 2018
More than two-dozen definitions of precision agriculture have been identified through the years — but which is the best and Read More
Industry NewsAg Equipment Manufacturers: 3 Trends to Shape Farming G…
July 2, 2018
Bottom line instead of brand loyalty. Tractors and harvesters will look more like computers. Data will drive productivity. These are Read More
Ag Retailer and Growers with tablet WinField United
Service ProvidersPrecision Ag Technology: Act Like You’ve Been There Bef…
July 2, 2018
One of my dad’s favorite, albeit borrowed, sayings was, “Act like you’ve been there before.” He was mostly referring to Read More