Environmental gradient

An environmental gradient is a gradual change in abiotic factors through space (or time). Environmental gradients can be related to factors such as altitude, temperature, depth, ocean proximity and soil humidity.

Species abundances usually change along environmental gradients in a more or less predictive way. However, the species abundance along an environmental gradient is not only determined by the abiotic factor but, also by the change in the biotic interactions, like competition, along the environmental gradient.