The levels of ecological organization can be broadly defined as the integrative level, hierarchical, population, community and ecosystem ecology.
Ecology covers a wide range of interacting organization levels reaching from micro-levels, such as cells, for instance, to planetary scale phenomena. An ecosystem can contain populations which aggregate into very distinct ecological communities.
To create a manageable framework for the study of ecology, the biological world in general is conceptually organized within a nested hierarchy, ranging in scale from genes, through cells and tissues; from organs and organisms into species, up to the biosphere level.
Population consist of individuals belonging to the same species, living, interacting and migrating through the same habitat and niche. The so-called Malthusian growth model is a primary law of population ecology and states that populations will decline or grow exponentially while the environment all individuals within the population experience remains constant.
This constitutes the study of interactions among a variety of interdependent species cohabiting a common geographic area. Measuring primary production within a wetland relating to consumption and decomposition rates is an example of studies within community ecology.
Ecosystem describes habitats within so-called biomes, which form dynamically responsive systems and integrated wholes, including both biological and physical complexes. Within every ecosystem are inseparable ties linking organisms to biological and physical components of the environment to which the organisms are adapted.
Much more detailed information on this subject as a whole, as well as the varying levels described may be found
here.
