Friday, 15 June 2018

EM Surveying - other uses for the data

Today it's our final blog for the 4-part series on EM Surveying that we've run you through over the last month. To date we've covered off:

Today Chris is going to take you on a run-through of what some of the other uses are for your EM Survey data are & how they can be applied on farm...

...I touched on probe placement at the end of the last post, so will continue where I left off. The EM layers are very useful for making sure you have your moisture probe in the most indicative soil type if you only put one probe in under a pivot for example, or if you have several soil types it ensures you can put probes under the lightest, heaviest and average soils, to make more informed management decisions on irrigation application. The topography information collected at the time of survey can also be used for determining soil moisture probe locations. 
Figure 1: Shallow EM Map with 3 probe locations in the different soil types. 

Where the land is undulating we can bring the elevation data into the equation for probe placement to find a flat area in each of the different soil types. We can also use a moisture probe in a dry land situation for adjusting inputs to the season (such as fertiliser, re-grassing & de-stocking).

When conduiting the EM survey we are using RTK GPS to log the EM data, this topography data and its derivatives are very powerful information layers. We can create water flow maps so you can see potential areas there may be issues for your Farm Environment plans, contour maps, and water flow animated videos as shown below. The Water Shed model mimics a large rainfall event, then over time shows where the water moves from quickly and where it hangs around longer. 

These Water Shed models highlight potential avoidance areas for planting, especially for nurseries and high value crops, in areas prone to heavy rainfall.

As you can see there are many ways people are using their EM survey data, and there are many other uses tailored to the individual client’s requirements. It is generally best to discuss with you your issues then we can work together on using the data to achieve the best solutions for you.

For any more information or to discuss your requirements give me a call.

Chris Smith
Operations Manager @ Agri Optics NZ Ltd