Increased soil acidity
Impact
Soil acidity is a naturally occurring phenomenon that can be escalated by human activity. The development of acidity is related to high soil concentrations of acidic cations, like hydrogen (H+) and aluminium (Al3+) in the soil. Acidification can be caused by accumulation of soil organic matter, nitrogen fixation, leaching of nitrate and fertiliser application. Crop harvesting can also cause soil acidity. Crops absorb elements from the soil for plant growth. When a crop is harvested, some of the soil elements that counter acidity development are removed; the net effect is an increase in soil acidity. When soil pH is too high it can have serious implications for soil health and vegetation growth.
Suggested indicator: Soil pH
Soil pH refers to the acidity or alkalinity of a soil. It is measured on a scale of 0 to 14, with a pH of 7 denoting neutrality. Higher pH values indicate alkalinity and lower values indicate acidity.
Increased soil acidity may be associated with:
| Potential associated impacts | Suggested indicators+ |
Reduced soil nutrient availability |
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Reduced vegetation growth and shallow root depth, resulting in:
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Reduced ground and canopy cover leading to:
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Reduced water quality as a result of:
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Reduced soil biota |
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+ Descriptions of indicators (PDF, 76K)* provides a brief description of each indicator including techniques and purpose.
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Last updated 7 September 2010
