Organic matter greatly influence the toxicity of aluminium. The toxicity of Al increases with decreasing pH and the mobilization of toxic aluminium ions has an adverse effect on the environment. This can result from changes in the pH of soil and water caused by increasing acidification of the surrounding atmosphere and acid rains. This can be indicated by the crop decline or failure, plant poisoning, and drying of forests.
A pH of surface layer of soil has low pH (less than 5) that can lead to soil acidity. This is a major concern around the world that affects crop production. Because of aluminium toxicity, the crop production is constrained to more than sixty percent of the total acid soil area in the world.
Moreover, silicon gets leached leaving behind aluminium in solid form known as aluminium oxyhydroxides because of acid soils has very low pH. The interaction of Al3+ with apoplastic, plasma membrane, and symplastic targets leads to toxicity and distracts the physical and cellular processes in plants. The common appearances are root growth repression, cellular modification in leaves, small and dark green leaves, yellowing and death of leaves, chlorosis, purpling and foliar necrosis.