Ecology (from , "house"; -λογία, "study of") is the
scientific analysis and study of interactions among organisms and their environment. It is an
interdisciplinary field that includes
biology,
geography and
Earth science. Ecology includes the study of interactions
organisms have with each other, other organisms, and with
abiotic components of their
environment. Topics of interest to ecologists include the
diversity, distribution, amount (
biomass), and number (
population) of particular organisms, as well as cooperation and competition between organisms, both within and among ecosystems.
Ecosystems are composed of dynamically interacting parts including
organisms, the
communities they make up, and the non-living components of their environment. Ecosystem processes, such as
primary production,
pedogenesis,
nutrient cycling, and various
niche construction activities, regulate the flux of energy and matter through an environment. These processes are sustained by organisms with specific life history traits, and the variety of organisms is called biodiversity.
Biodiversity, which refers to the varieties of
species,
genes, and
ecosystems, enhances certain
ecosystem services.