An energy pyramid is a graphical representation designed to show biomass or bio productivity at each trophic level in a given ecosystem. An energy pyramid is always upright because when energy flows from a particular trophic level, some energy is lost as heat at each step. Thus, total amount of energy available for utilisation in top levels is always less than energy available in lower levels. Therefore in pyramid of energy in which each bar indicates amount of energy present at each trophic level in a given time

• Ecological succession is process of change in species structure of an ecological community over time. The time scale can be decades or even millions of years after a mass extinction.
• Evolution is process of heritable change in populations of organisms over multiple generations.
  
• Selection is preferential survival and reproduction or preferential elimination of individuals with certain genotypes (genetic compositions), by means of natural or artificial controlling factors.
• The specialization is adaptation of an organism or organ to a special function or environment.

The biochemical cycle is also called a biogeochemical cycle or nutrient cycle. The biochemical cycle with gaseous phase includes various cycles like carbon cycle, nitrogen cycle, oxygen cycle. Nitrogen, carbon, and oxygen are found in gaseous form in atmosphere. Calcium cycle, sodium cycle, phosphorus cycle, iron cycle, magnesium cycle, sulphur cycle are sedimentary cycles.

• Disclimax is ecological community that displaces natural climax community due to interruptions by human activities and consists of organisms that are foreign to that region.
• Plagioclimax is stage when succession doesn't reach climax and stops due to various interruptions such as destruction of vegetation.

Ecological services are said to be products of ecosystem processes. It is thought that biodiversity carries a hefty price tag. Out of total cost of various ecosystem services, a 50 percent cost is required for soil formation.

Oxygen and Nitrogen are inert gases in air.

An ecosystem is an interaction between living and non-living components of an environment. The standing state of an ecosystem is total amount of inorganic nutrients which may be calcium, phosphorus etc in an ecosystem. They are only non-living components of an ecosystem. 

An ecological pyramid is a graphical representation designed to show biomass or bio productivity at each trophic level in a given ecosystem. A "pyramid of biomass" shows relationship between biomass and trophic level by quantifying biomass present at each trophic level of an energy community at a particular time. It is a graphical representation of biomass  present in unit area in different trophic levels. The pyramid of biomass may be "inverted".