The following outline is provided as an overview of and topical guide to ecology:

Ecology – scientific study of the distribution and abundance of living organisms and how the distribution and abundance are affected by interactions between the organisms and their environment. The environment of an organism includes both physical properties, which can be described as the sum of local abiotic factors such as solar insolation, climate and geology, as well as the other organisms that share its habitat. Also called ecological science.

Ecology can also be classified on the basis of:

Ecology is a broad discipline comprising many subdisciplines. The field of ecology can be subdivided according to several classification schemes:

Arranged from lowest to highest level of organisation:

Ecology has also inspired (and lent its name to) other non-biological disciplines such as:

Biogeographic realm – Broadest biogeographic division of Earth. The World Wildlife Fund (WWF) developed a system of eight biogeographic realms (ecozones):

Ecoregion – Ecological and geographical area