Deltares and NMI-agro developed a do-it-yourself protocol for measuring for indicative measurements of mineral nitrogen (Nmin) contents in soil using the Aquality App (formerly: Nitrate App). See the visual user guide for more details.
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- Kitchen scale
- Non-recycled toilet paper
- Standard 450 ml Dopper drinking bottle (see dopper.com)
- Smartphone with the Deltares Nitrate Aquality App from the the Google App Store (for Android) or the App Store (iOS)
- Jar of nitrate test strips from Hach
- Nitrate Aquality App reference card
- Other: pen, paper, teaspoon, nitrate-free water
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Steps for taking a soil Nmin measurement
- Take a soil sample
- Add 340 ml or 340 g water to the Dopper bottle (until the start of the taper)
- Tare Place the bottle on the scale (and set it to zero. Add your soil sample until it reaches the top of screw thread
- Write ), add soil until the screw thread, write down the weight of the added soil
- Close the Dopper bottle and shake firmly for 1 minute
- Stick a folded piece of toilet paper 0.5 cm into the sample to extract clear water
- Tear-off the bottom (brown) half of the paper so only clear water is left
- Squeeze a drop of clear water out of the toilet paper on the upper reaction surface of a Hach Nitrate test strip
- Tap the 'timer' icon and wait for 60 seconds
- Place the strip on the black line Give the test strip a fingerflick to remove excess water and put it on the reference card
- Use the Nitrate app to scan the card 60s after adding the water drop
- and tap the 'camera' icon to take a picture of the reference card, or tap 'manual input' to add the details
- Check your measurement details. Select the category 'Soil Nmin', add the sample depth and weight , and send the resultof the soil sample, and tap 'submit' to upload it.
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