TABLE 4.
Analysis of tap water and reverse osmosis (RO) water used in experiment 3.
| Measurement | Units | Irrigation Water | RO Water |
| pH | n.a. | 7.5 | 7.1 |
| EC | (dS⋅m−1) | 0.7 | 0.06 |
| NO3-N | (mg⋅L−1) | 0.8 | – |
| NH4-N | – $ | – | |
| P | 1.1 | – | |
| K | 3 | – | |
| Ca | 102 | – | |
| Mg | 38 | – | |
| Na | 14 | 13 | |
| S | 35 | – | |
| Zn | – | – | |
| Mn | 0.1 | – | |
| Fe | 0.47 | – | |
| Cu | 0.05 | 0.03 | |
| B | 0.03 | 0.03 | |
| Al | – | – | |
| Mo | – | – | |
| Si | 7 | 1 | |
| Cl | 38 | 3 | |
| Alkalinity | 250 | 20 | |
| CO3 | – | – | |
| HCO3 | 305 | 24 |
Values for electrical conductivity (EC), nitrate-nitrogen (NO3-N), ammonium-nitrogen (NH4-N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sodium (Na), sulfur (S), zinc (Zn), manganese (Mn), iron (Fe), copper (Cu), boron (B), aluminum (Al), molybdenum (Mo), silicon (Si), carbonate (CO3), and bicarbonate (HCO3) are shown.
$Undetected or levels are lower than the sensitivity of equipment.