Aluminum

Soils contain an average of 7% total aluminum (Al), and under acidic conditions, aluminum is solubilized (1), increasing availability to plants and aquatic animals. Soil acidification due to application of fertilizers, growing of legumes, or acid rain is an increasing problem in agricultural and natural ecosystems (2-4).

No conclusive evidence suggests that aluminum is an essential nutrient for either plants (5) or animals (6,7), although there are a few instances of beneficial effects. Aluminum is toxic to plants and animals, interfering with cytoskeleton structure and function, disrupting calcium homeostasis, interfering with phosphorus metabolism, and causing oxidative stress (discussed in later sections).