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.[1]

At an ecotone, species abundances change relatively quickly compared to the environmental gradient.

The species distribution along environmental gradients has been studied intensively due to large databases of species presence data (e.g. GBIF)

Environmental Gradients are linked to Connectivity and natural disturbance when considering river systems. A river restoration scheme must consider all of these factors before undertaking a program as these three factors are what leads to a larger biodiversity.

Each species are not found in every type of habitat or in every part of the world. Within the environment there are multiple factors which affects organisms. The organisms in the polar region can not survive the climate at the equator.

Huisman–Olff–Fresco models describe unimodal species responses over an environmental gradient.