The Future of the Biosphere

The Biosphere in Education

History of the Biosphere Concept

The term "biosphere" originated with the geologist Eduard Suess in 1875, who defined it as "the place on earth's surface where life dwells". Vladimir I. Vernadsky first defined the biosphere in a form resembling its current ecological usage in his long-overlooked book of the same title, originally published in 1926. It is Vernadsky's work that redefined ecology as the science of the biosphere and placed the biosphere concept in its current central position in earth systems science.

Levels of organization of Ecology, highlighting the Biosphere. (Credit: Erle Ellis)

The biosphere is a core concept within Biology and Ecology, where it serves as the highest level of biological organization, which begins with parts of cells and proceed to populations, species, ecoregions, biomes and finally, the biosphere. Global patterns of biodiversity within the biosphere are described using biomes.

In earth science, the biosphere represents the role of living organisms and their remains in controlling and interacting with the other spheres in the global biogeochemical cycles and energy budgets. The biosphere plays a central role in the biogeochemical processing of carbon, nitrogen, phosphorus, sulfur and other elements. As a result, biogeochemical processes such as photosynthesis and nitrogen fixation are critical to understanding the chemistry and physics of earth systems as a whole. The physical properties of the biosphere in terms of its surface reflectance (albedo) and exchange of heat and moisture with the atmosphere are also critical for understanding global circulation of heat and moisture and therefore climate. Alterations in both the physics (albedo, heat exchange) and chemistry (carbon dioxide, methane, etc.) of earth systems by the biosphere are fundamental in understanding anthropogenic global warming.

The Biosphere II "experiments", which were conducted in the early 1990s in Arizona using private funding, enclosed a complex array of plants and animals together with humans in a sealed greenhouse complex which included a large "ocean". Within a short time, this "experimental biosphere" demonstrated how little we understand biosphere I (the biosphere of our planet): the project failed to replicate the basic biogeochemical functions that support life on Earth. Without resorting to drastic chemical interventions to inject oxygen and reduce toxic levels of carbon dioxide, it was impossible to support human life in the complex. Moreover, many keystone species, such as pollinators died off within a short time.

Many now see this as a good analogy for the current changes in atmospheric composition we are causing by rapidly burning off the fossil carbon captured by plants over millions of years, and by our conversion of forests to croplands. By releasing carbon stored by the biosphere over geologic time back to the atmosphere at unprecedented rates, humans are causing rapid global warming, and this warming is further altering global biogeochemical cycles and patterns of biodiversity across the biosphere. Anthropogenic climate change together with land use change and other anthropogenic alterations of the biosphere and other spheres have now reached such a high level that some earth scientist are now calling for the recognition that we have now entered a new, human-dominated, geologic era: the anthropocene.

Lecture5. Биосфера и ее устойчивость

Владимир Иванович Вернадский - русский и советский минеролог и геохимик, который считается одним из основоположников геохимии, биогеохимии, и радиогеологии.

Вернадский впервые популяризировал понятие ноосферы и углубил представление о биосфере в значительной степени признаны научным сообществом сегодня. "Биосфера" слово было предложено австрийским геологом Эдуард Зюссом, которым Вернадский встречались в 1911 году.

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