Environmental Engineering Reference
In-Depth Information
Figure 18.13
The influence of pH on the availability of plant
nutrients and on the activity of micro-organisms.
ium, phosphorus, molybdenum and boron. Such soils may also indicate toxic amounts of
zinc, manganese, nickel and other elements due to increased solubility. Soil
microorganisms are also most active and beneficial at pH values in the range 6·0 to 8·0.
These important facts explain the importance of the farming practice of liming as a means
of raising pH to about 6·0 to 6·5, enhancing the availability of nutrients to plants. Values
in the range 8·0 to 8·5 often
Figure 18.14
The influence of pH on the solubility (toxicity)
of chemicals in soils.
