Which Species Dominate Which Habitat?

86 percent of all living biomass, around 470 billion tonnes of carbon, can be found in terrestrial environments. According to scientific findings aggregated by Our World in Data, this large percentage is owed to almost all plants, which make up 82.4 percent of biomass on the planet, being found on land. While trees, flowers, mosses and similar organisms dominate the land, the sea is ruled by a different species as our chart shows.

Animal biomass, although only amounting to roughly two billion tonnes of carbon and therefore only representing a small share of the overall living biomass, is most prevalent in marine environments. 78 percent of all fauna in terms of biomass can be found in water, largely due to fish alone making up one third of all animal biomass. Protists like algae and amoebas are almost cleanly split between terrestrial and marine environments, while bacteria and single-celled prokaryotes are dominant in deep subsurface areas. This special habitat can be found either below the terrestrial surface or the ocean floor and starts at a depth of 50 meters or deeper. Overall, the world is home to an estimated number of 8.8 million species with around 1.7 million of them already being identified and described.

To further highlight the importance of marine environments to animals and humans particular, the United Nations established June 8 as World Ocean Day in 2009. This year, the focus will be put on actions geared towards achieving the protection of at least 30 percent of the planet's lands, waters and oceans by 2030. As of now, only 17 percent of land and 8 percent of the world's oceans are protected, a number that, according to UN experts, needs to significantly improve in order to mitigate some of the dangers of climate change and guarantee healthy ecosystems across the globe.