Hanna Instruments HI 83900-30 - Manual (Page 3)

4 5
FUNCTIONAL DESCRIPTION
1. Rubber cap
2. Soil solution sampler tube
3. Porous ceramic tip
4. 30 mL syringe (pump)
5. Rubber suction capillary
6. Finger clamp
GENERAL USE / OPERATING PRINCIPLES
The HI 83900 suction lysimeter is built with a porous ceramic cap connected to a
transparent tube for soil solution extraction. A rubber capillary is inserted in the tube
passing through a rubber cap and reaching the ceramic tip.
The lysimeter is an ideal tool for collecting soil solution samples and then perform
quantitative chemical analysis. In this way the operator can easily monitor the level of
fertilization nutrients, such as ammonia, nitrate, phosphorous and potassium.
The ceramic tip of the lysimeter can be used in all types of soil, and it is made of
sinterized material that does not react with nutrient elements. The soil solution, there-
fore, is not affected by the chemical composition of the ceramic cap, and the test
results are always precise and reliable.
Use our chemical test kits or photometers for accurate analysis (see the HANNA
instruments
® general catalog or visit our web site at www.hannainst.com for a
complete list of equipments, reagents and accessories).
The HI 83900 allows to extract a solution from the soil by creating a vacuum (nega-
tive pressure or suction) inside the sampler tube, that exceeds the soil water tension.
This will establish an hydraulic gradient for the solution to flow through the porous
ceramic cap and into the lysimeter tube. Typically, a vacuum of about -60 cb (cen-
tibar) should be drawn.
For better monitoring the soil solution composition throughout an entire growth pe-
riod of crops, at least two lysimeters should be installed in the root zone of a represen-
tative plant, one at the upper part and the other in the lower part of the root zone.
For better accuracy and repeatability of results, it is recommended to replicate the
above described installation in at least two more locations.