PRONOVA Stelzner EC 2000, Technical Instructions

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47
GB
5.1 General information
about using the NITRAT 2000
Determining nitrate in soil samples
100 g fresh soil sample
(take out large
chunks and stones and sift through).
Add 100 ml alum to a 250-ml sealable bottle .
Seal bottle and shake for thirty minutes .
Wait for the soil components to settle out.
Then measure the nitrate content in the
remaining solution by immersing and briefly
moving the nitrate electrode in the unclear
solution. The measured solution should stand
1.5 to 2 cm deep and the nitrate electrode
should be submerged in the solution up to the
diaphragms. You can take down the measu-
red value on the NITRAT 2000 as soon as the
value has stabilized.
Measured value in mg/l nitrate
Disregarding the soil moisture, the measured
value in mg NO³/l corresponds to kg NO³-N/
ha.
Determining nitrate in plant samples
10 – 50 g fresh plant sample
(chopped up
finely) - weighted sample
Add 100 ml alum to a 250-ml sealable bottle .
Blend thoroughly with an immersion blender
and then shake for thirty minutes .
In order to measure, immerse the elec-
trode until the unclear solution is over the
diaphragms. Then move the electrode around
in the solution briefly. You can take down the
measured value on the NITRAT 2000 as soon
as the value has stabilized.
Calculating the nitrate content in mg/kg for
plant material:
NITRAT 2000