Table 1.
Chemical speciation reactions for widely studied neutral and alkaline salt types dissolved in rhizosphere solution (after [12]).
| Neutral Salt Type | pH | Prevalent Ions (%) | Precipitated Forms |
|---|---|---|---|
| Sodium chloride NaCl |
7.94 | Na+ 98; Cl− 98 |
Magnesite Dolomite Hydroxyapatite Calcite Huntite Vaterite Artinite |
| Potassium chloride KCl |
7.94 | K+ 98; Cl− 98 |
|
| Magnesium chloride Mg Cl2 |
7.93 | Mg2+ 77; Cl− 98; Mg-OC 10; MgSO4 4; MgHCO3+ 4; MgCl+ 1 |
|
| Calcium chloride CaCl2 |
7.93 | Ca2+ 78; Cl− 98; Ca-organo-complexed forms 6; CaSO4 6; CaHCO3+ 5; CaCl+ 1 |
|
| Sodium sulphate Na2SO4 |
7.94 | Na+ 98; SO42− 72; CaSO4− 16; MgSO4− 10 |
|
| Alkaline Salt Type | pH | Prevalent Ions (%) | |
| Sodium hydrogencarbonate NaHCO3 |
8.01 | Na+ 98; HCO3− 92; CaHCO3+ 2; CaCO3 1 |
|
| Sodium carbonate Na2CO3 |
8.08 | Na+ 98.2; HCO3− 92; CaHCO3+ 2.2; CaCO3 1.3 |
|
| Potassium carbonate K2CO3 |
8.03 | K+ 98; HCO3− 92; CaHCO3+ 2; CaCO3 1 |
|
| Magnesium carbonate MgCO3 |
8.07 | Mg2+ 75; Mg-organo-complexed forms 10; MgHCO3+ 5; MgSO4 4; HCO3− 91; MgHCO3+ 2 |
|
| Calcium carbonate CaCO3 |
8.07 | Ca2+ 76; Ca-organo-complexed forms 6; CaHCO3+ 6; CaSO4 6; HCO3− 90; CO32− 1 |