What soil pH is typically found in regions with heavy rainfall?

Soil pH in regions with heavy rainfall is typically acidic. This is primarily due to the leaching process that occurs when rainwater infiltrates the soil. In areas with significant precipitation, the water can dissolve and carry away basic ions such as calcium and magnesium, which are critical for maintaining a neutral or alkaline pH. As these basic cations are removed, weaker acids such as carbonic acid from the atmosphere and organic acids produced by decomposing plant material can dominate, leading to a more acidic soil environment.

Regions with heavy rainfall often feature ecosystems such as rainforests, where the constant moisture not only promotes rapid vegetation growth but also enhances the breakdown of organic material, contributing further to acidity. Additionally, certain parent materials and vegetation types can also influence soil pH in these regions, but heavy rainfall typically leads to lower pH values overall, indicating more acidic soils. Thus, the link between heavy rainfall and increased soil acidity is well-established in soil science.