Biosphere: Quick Facts

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Diagram illustrating Earth's environmental spheres, with labeled sections showing the geosphere (land and crust), biosphere (living things), atmosphere (air), and hydrosphere (water), each extending vertically from the Earth's surface.

A circular chart illustrates the estimated number of known living species, divided into segments for plants, monerans, protists, fungi, animals excluding insects, and animals that are insects only, with insects occupying the largest portion.

Diagram showing energy transfer through an ecosystem, with solar energy absorbed by plants (producers) at the base, then moving up to herbivores (primary consumers), small carnivores (secondary consumers), and large carnivores (tertiary consumers), while most energy is lost as heat at each step.

Diagram showing energy flow and nutrient cycling in the biosphere, with sunlight powering producers like plants and algae, which feed consumers. Arrows illustrate nutrient movement through detritus, microbes, soil, water, sediments, and the atmosphere, including fossil fuel formation and weathering.

Colorful diagram of the nitrogen cycle showing how nitrogen moves through the atmosphere, biosphere, and soil. It illustrates natural processes like nitrogen fixation, assimilation, ammonification, nitrification, and denitrification, as well as human activities such as fertilizer use and industrial emissions, with arrows and labels connecting elements like plants, animals, bacteria, and factories.

nitrogen fixation

A diagram shows a terrestrial reptile on rocks, illustrating energy exchanges with the environment through arrows labeled for reflected radiation, evaporation, direct solar radiation, thermal reradiation, convection, and conduction of heat between the lizard and the rock. Environmental and body temperatures are also noted.

Diagram comparing osmotic regulation in freshwater and marine teleost fish, showing water and ion movement through skin and gills, urine concentration, and active uptake or secretion processes.

World map highlighting Earth's terrestrial biodiversity hot spots in red, showing regions with exceptionally high levels of species richness and endemism. These hot spots are distributed across parts of Central and South America, the Caribbean, Mediterranean basin, Africa, Madagascar, South and Southeast Asia, and islands in the Pacific and Indian Oceans, as well as select areas in North America, Europe, Australia, and New Zealand.

Small squirrel peeking out of a snowy bank, with a blue circle surrounding it.

How greenhouse gases affect Earth's climate

The importance of nitrogen and phosphorus in ecosystems

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Topics

population biological productivity microbiome biotic interaction energy flow flora and fauna biogeographic region biodiversity natural disaster ecosystem Climate cell plate tectonics hydrosphere earthquake continental landform ocean erosion Weather DNA

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