User Guide

4
adding lime, the effects in clay soil can last for as long as 10 years, but only 2-
3 years in a sandy soil.
For an acid soil, we can use substances such as lime, dolomitic, limestone and
marl, according to the nature of the soil (Tab.1).
Soil Ameliorants Clay soil Silty soil Sandy soil
CaO 30-50 20-30 10-20
Ca(OH)
2
39-66 26-39 13-26
CaMg(CO
3
)
2
49-82 33-49 16-33
Ca CO
3
54-90 36-54 18-36
Tab.1. Quantity (q/ha) of pure compound necessary to increase 1 unit of pH
High pH levels can depend on different elements, hence, there are different
methods for its correction.
- Soils rich with limestone :
Add organic matter (this is due to the fact that non-organic ameliorants such as
sulfur and sulfuric acid might not make economic sense due to the large
quantities needed).
- Alkaline-saline soils :
Alkalinity is due to the presence of salts (in particular a high concentration of
sodium can be harmful).
Irrigation washes away salts, hence, an appropriate use of irrigation can provide
positive results (drop-irrigation being the most recommended).
If alkalinity is caused by sodium, it is recommended to add substances such as
gypsum (calcium sulfate), sulfur or other sulfuric compounds (Tab.2). Also in
this case, a cost evaluation is necessary.
Soil ameliorants (pure compounds) Quantity (Kg)
Calcium chloride: CaCl
2
· 2H
2
O85
Sulfuric acid: H
2
SO
4
57
Sulfur: S 19
Iron sulfate: Fe
2
(SO
4
)
3
· 7H
2
O 162
Aluminum sulfate: Al
2
(SO
4
)
3
129
Tab.2. Quantities provide the same result as 100 Kg of gypsum
Procedure for direct ground measurement
1) Dig, discarding 5 cm of topsoil
2) Perforate the soil (with HI 721319 soil drill) to a depth of about 20 cm or
more
3) If the soil is dry, moisten it with a small amount of distilled water