Ecology can be divided into areas of study ranging from the ecology of individual organisms to the dynamics of ecosystems and landscapes. Ecology reveals the richness of the biosphere – the entire portion of Earth inhabited by life – and can provide the basic understanding that will help us to conserve and sustain that richness, now threatened more than ever by human activity. Ecology can be divided into areas of study ranging from the ecology of individual organisms to the dynamics of ecosystems and landscapes.
While each of these sub fields has some unique terminology and scientific concerns, modern ecological studies increasingly cross the boundaries between traditionally separate areas.
Organismal ecology, which may be subdivided into the disciplines of physiological ecology, evolutionary ecology, and behavioral ecology, concerns how an organism's structure, physiology, and (for animals) behavior meet the challenges posed by the environment. Population ecology concentrates mainly on factors that affect how many individuals of a particular species live in an area.
Community ecology deals with the whole array of interacting species in a community. An ecosystem consists of all the abiotic factors in addition to the entire community of species that exist in a certain area. Landscape ecology deals with arrays of ecosystems – just two examples are, a corridor of trees lining a river flowing through a sparsely vegetated plain, or patches of coral reef surrounded by turtle grass – and how they are arranged in a geographic region. The biosphere is the global ecosystem- the sum of all the planet's ecosystems. Restoration ecology is the scientific study of repairing disturbed ecosystems through human intervention. Whereas conservation biology is often focused on assessing and preventing ongoing degradation, restoration ecology seeks to actively reverse such degradation.