Improving Returns with a Soil Conductivity Map and Precision Farming ​

Conductivity measures the ability of a particular material to conduct or transmit an electrical charge. This is a property of the material just like porosity or density are other properties.

Its usefulness comes from the fact that sands have low conductivity, while silts have medium, and clay have high conductivity. Although the correlation of soil conductivity and yield is still under research, initial results are promising, particularly when yields are affected by their capacity to retain water.

The importance of soil conductivity maps rely mainly on the ability to delineate similar and contrasting regions of the field. This is due to the fact that the main factor contributing to soil conductivity is soil texture in non-saline fields.

In precision agriculture, soil conductivity has many potential uses, which include some of the following: 

• Directed sampling
• Various corn populations on the basis of top soil depth
• Different herbicide rates on the basis of texture and organic matter
• Different fertilizer rates
• Guiding experiments
• Layering with government soil maps
• Soil salinity identification

Directed Sampling

Soil conductivity can be used in precision agriculture via sampling on evenly spaced grids. But, this practice can become cost prohibitive if very small grid sizes are needed for capturing enough spatial variations.

So before samples are taken for analysis, this will establish the need to determine the variability in the field. With proper knowhow in soil variability, you can choose sample locations to ensure their representativeness.

The designed set of sample points is now called targeted or directed sampling.

Top Soil Depth

A soil conductivity map can also be used to direct sense soil depth where production is limited. This has shown an increase in net income per acre as it is a cost-effective technique.

Variable Use of Herbicides

Properly using herbicide rates can also save money, protect the environment, and increase its effectiveness. This will be based on the soil texture and organic matter recommended for soil-applied herbicides.

Guiding Experiments

Soil conductivity maps could be useful to determine the site’s layout and derive each variable’s response to the soil properties of the field. This can be applicable for some precision agriculture adopters testing inputs like fertilizer applications, seed varieties, and tillage practices, and conducting on-farm trials.

Layering With Government Soil Maps

Different soil series are mapped as vector lines and polygons in soil maps, but soils inside the field would change as a continuum. However, with the use of soil electrical conductivity and GPS via direct sensing, it can produce geo-referenced or detailed soil maps.

In conclusion, there is a potential to enhance precision agriculture using soil electric conductivity. This is done by the mapping and measuring of soil electric conductivity, as there is a relationship between soil electric conductivity and the physical properties of soil.

Soil conductivity maps can be done via soil electric conductivity measurements for the production of geo-referenced soil maps. Thus, it can be used to interpret yield maps, design on-farm trials, guide soil sampling, and help derive input recipes for crop protection chemicals, nutrients, and seeds.

Precision Agronomics is located at 9438 West SR 28 in West Lebanon, IN and is proud to serve: Marshfield, Johnsonville, Foster, Stone Bluff, Bismarck, and the surrounding areas. Contact us today for more information!

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