Oceans, land, and deep subsurface: how is life distributed across environments?
Where do we find life on earth? Despite being vast, the oceans are home to just 1% of life – but the majority of animals. See how the different lifeforms are split across these global environments.
We looked at how global biomass is distributed between taxonomic kingdoms. How is it distributed between environments?
The visualization here provides a snapshot of how life spans across the planet's environments. This summary is based on the findings of research by Bar-On, Phillips & Milo published in the Proceedings of the National Academy of Sciences (PNAS).1
There are three high-level habitat environments: land, marine, and deep subsurface environments. Deep subsurface environments can be terrestrial or below the ocean floor, but represent habitats deep below the surface – extending from around 50 metres to thousands of metres below the surface.2
Most of life exists on land — 86% of biomass. This is because almost all plant life – mostly trees – is terrestrial. The authors estimate that marine plants, for example seaweed, make up less than 1 billion tonnes of carbon. This is less than 0.2% of total plant biomass.3 Most bacteria and archaea exists in the deep subsurface, meaning 13 percent of global biomass thrives in this environment.
Despite dominating our planet in terms of area and volume – taking up more than 70% of global surface area – the oceans are home to just 1% of biomass. But they do dominate the animal kingdom: 78% of animal biomass lives in the marine environment.
With lifeforms ranging in size from the microscopic cellular level to large lifeforms that span tens of hectares,4 it is impossible to contextualize life on Earth through experience or intuition alone.
Just look at the viruses that live in the sea: while each one of them is tiny, if we placed all the viruses end-to-end they would stretch for 10 million light years. That is around 100 times the distance across our own galaxy.5 On land the scale is just as mindblowing: there are more than 1016 prokaryotes in a ton of Earth's soil – orders of magnitude more than the 'mere' 1011 stars in our galaxy.6
Looking at the big numbers allows us to understand our planet and our place in it.
Endnotes
Bar-On, Y. M., Phillips, R., & Milo, R. (2018). The biomass distribution on Earth. Proceedings of the National Academy of Sciences, 201711842. Available at: http://www.pnas.org/content/115/25/6506.
Parnell, J., & McMahon, S. (2016). Physical and chemical controls on habitats for life in the deep subsurface beneath continents and ice. Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 374(2059), 20140293.
Total plant biomass is 450 billion tonnes of carbon, so in a maximum case: (1 billion tonnes / 450 billion tonnes) * 100 = 0.02 percent.
Pando (a tree), also known as the 'Trembling Giant' is a colony of aspen in Utah and named the world's largest organism. It is determined to be a single living organism based on identical genetic markers and a single underground root system.
Suttle, C. A. (2005). Viruses in the sea. Nature, 437(7057), 356-361.
Curtis, T. P., & Sloan, W. T. (2005). Exploring microbial diversity--A vast below. Science, 309(5739), 1331-1333.
Cite this work
Our articles and data visualizations rely on work from many different people and organizations. When citing this article, please also cite the underlying data sources. This article can be cited as:
Hannah Ritchie (2019) - “Oceans, land, and deep subsurface: how is life distributed across environments?” Published online at OurWorldInData.org. Retrieved from: 'https://ourworldindata.org/life-by-environment' [Online Resource]BibTeX citation
@article{owid-life-by-environment,
author = {Hannah Ritchie},
title = {Oceans, land, and deep subsurface: how is life distributed across environments?},
journal = {Our World in Data},
year = {2019},
note = {https://ourworldindata.org/life-by-environment}
}
Reuse this work freely
All visualizations, data, and code produced by Our World in Data are completely open access under the Creative Commons BY license. You have the permission to use, distribute, and reproduce these in any medium, provided the source and authors are credited.
The data produced by third parties and made available by Our World in Data is subject to the license terms from the original third-party authors. We will always indicate the original source of the data in our documentation, so you should always check the license of any such third-party data before use and redistribution.
All of our charts can be embedded in any site.