SWFC is excited to offer a new soil scanning service, which can assess farm soil characteristics with far more detail — and far more quickly — than traditional soil testing methods
The overall health and profitability of a farm ultimately rests on its soil. If we don’t understand what’s happening at soil level we can’t effectively plan future farm management.
Over the last year, we have been reviewing the potential for the use of soil scanning as a tool for measuring and monitoring soil properties. Soil scanning offers the potential for assessment of soil characteristics across a field with far more detail than can be expected from traditional soil testing – and in a much shorter time.
Types of soil scanner
There are currently three different types of scanner in use in the UK that utilise the following different technologies to assess soil:
- Electromagnetic induction (EMI)
- Electroconductivity (EC)
- Gamma-ray spectrometer
Electromagnetic Induction and Electroconductivity
EMI soil scanning works by sending out an electromagnetic field that is conducted through the soil. Different properties in the soil affect the electromagnetic field and a receiver records the amended signal which is then converted to EC measurements. EC soil scanning is similar but measures conductivity directly by contact with the soil.
Research has shown that EC measurements are affected by a range of soil parameters including the amount and type of clays in the soil and water content. As a rough rule of thumb, the heavier the soil, the better the conductivity.
An example from EMI scanning is shown below:
Image used with permission from Precision Decisions Ltd.
Gamma-ray spectrometer soil scanning works in a different way. It is based on the measurement of naturally occurring radioactivity emitted by nuclides in minerals of the soil. The composition of minerals in a particular soil is influenced by the geology underlying the soil and there is a greater abundance of nuclide-rich minerals in clay than there is in sand. As with EMI and EC scanning, the impact of different soil properties on the measurement taken by the scanner can be converted into useable data.
Using the mapping
The maps created by soil scanning can be used in farm management decisions, such as variable input rates for fertiliser and lime or variable seed rates. For these examples, knowledge of the better quality soils across an individual field or block of land could allow for reduced input rates (and reduced costs) on the better soils without impacting yield. Scanning maps can also be used when planning grazing as a way to move nutrients around the farm from natural livestock excretion.
Adding soil sampling
Scanners use GPS systems to precisely locate their results. Scanning is a one-off process to provide baseline data and mapping of each scanned field. These maps are then used to identify points in the field where additional soil sampling is needed – the number of points dependent on the variability within each field. These sampling points are also identified by GPS so that future samples can be taken at the same location to review the impact of farm management over time.
The best soil scanning service
SWFC wanted to work with a scanning system that met the following criteria:
- Can be used on grassland and early-stage arable crops, as well as bare ground
- Quick results that are easy to access and understand
- Scanning system integrated with soil sample collection and analysis
- Good back-up and support
With this in mind, the scanning service we offer is EMI scanning from Precision Decisions Ltd., combined with soil sampling at points identified by the analysis of scanning data. The soil sampling covers:
- Nutrient analysis — pH, P, K, Mg, Ca, S and Micronutrients (Cu, Fe, Na, B, Mn, Zn)
- Organic matter/Soil carbon (0-10cm and 10-30cm)
- Bulk density (0-10cm and 10-30cm)
The Wintex 2000 hydraulic automatic sampler can take soil samples up to 60cm deep [Image used with permission from Precision Decisions Ltd.]
One particular soil parameter that is becoming increasingly important is soil carbon. With scanning and targeted sampling, it is possible to assess carbon at different soil depths; these results then can be used in existing carbon measurement and management tools. At SWFC we are using scanning and sampling data alongside Farm Carbon Cutting Toolkit assessments. This helps us understand the carbon footprint on a per farm or per tonne of production basis, as well as starting to build a picture of carbon sequestration and where carbon savings can be made. If we understand current soil carbon levels, SWFC can then advise on changes in management to improve soil health and carbon stocks.
Planning for the future
With the information from scanning and sampling, we can draw up individual plans for each scanned farm – down to individual field level – for the short, medium and long-term.
We know that the overall health and profitability of a farm rests on its soil. If we don’t understand what’s happening at soil level we can’t effectively plan future farm management. Our overall aim is to support farmers to improve their soil health. We’re embracing soil scanning as a tool to help to achieve that.
If you would like to discuss how our new soil scanning service can help your farm business, please do not hesitate to get in touch. Call for a no-obligation chat on 01503 220002 or send us a message on our Contact Page.