Ecosystems exist underground, on land, at sea, and in the air. Organisms in an ecosystem acquire energy in various ways, which is transferred between trophic levels as the energy flows from the base to the top of the food web, with energy being lost at each transfer. Mineral nutrients are cycled through ecosystems and their environment. Water, carbon, nitrogen, phosphorus, and sulfur are particularly important. All of these cycles have major impacts on ecosystem structure and function. Ecosystems have been damaged by various human activities that alter the natural biogeochemical cycles due to pollution, oil spills, and events causing global climate change. The biosphere’s health depends on understanding these cycles and how to protect the environment from irreversible damage. Earth has terrestrial and aquatic biomes. There are eight major terrestrial biomes: tropical rainforests, savannas, subtropical deserts, chaparral, temperate grasslands, temperate forests, boreal forests, and Arctic tundra. Temperature, precipitation, and variations in both are key abiotic factors shaping the composition of animal and plant communities in terrestrial biomes. Sunlight is an important factor in bodies of water, especially very deep ones, because of photosynthesis’s role in sustaining certain organisms. Other important factors include temperature, water movement, and salt content. Aquatic biomes include both freshwater and marine environments. Like terrestrial biomes, aquatic biomes are influenced by abiotic factors. In the case of aquatic biomes, the abiotic factors include light, temperature, flow regime, and dissolved solids.
Energy Flow through Ecosystems by OpenStax is licensed under CC BY 3.0. Modified from the original by Matthew R. Fisher.
Biosphere by Connexions <https://archive.org/details/cnx-org-col11325/mode/2up. Modified from the original by Tom Theis and Jonathan Tomkin.
OpenStax College. (2013). Concepts of biology. Retrieved from http://email@example.com.