In ecology, base-richness is the level of chemical bases in water or soil, such as calcium or magnesium ions.
[1] Chemical bases are alkalis, hence base-rich environments are either neutral or alkaline.
There is a positive correlation between base-richness and calcium (Ca), magnesium (Mg), and carbonates (HCO3, and a negative correlation with pH, Iron (Fe), Manganese (Mn), and Aluminum (Al).
[citation needed] Base-rich terrestrial environments are characteristic of areas where underlying rocks (below soil) are limestone.
Base-poor environments are characteristic of areas where underlying rocks (below soil) are sandstone or granite, or where the water is derived directly from rainfall (ombrotrophic).