CK12 Earth Science

Flow of Energy in Ecosystems Energy cannot be created or destroyed. Energy can only be changed from one form to another. This is ...

Figure 18.9: A simple food chain from a Swedish lake. Not pictured: algae eaten by the shrimp; Shrimp are eaten by a small fish, ...

Since some organisms feed at more than one trophic level, the food chain does not adequately describe the passage of energy in a ...

the soil and are taken up by plants. Nutrients can be brought in from other regions, perhaps carried to a lake by a stream. When ...

Figure 18.11: This hummingbird and flower each benefit from the mutualism of their rela- tionship. ( 8 ) Figure 18.12: The relat ...

Figure 18.13: These tiny mites are parasitic on a harvestman. ( 23 ) ...

Lesson Summary Each species fills a niche within an ecosystem. Each ecosystem has the same niches, although the same species do ...

commensalism A relationship between two species in which one species benefits and the other species is not harmed. community All ...

parasitism A symbiotic relationship between two species in which there is a parasite and a host. The parasite gains nutrition fr ...

18.2 The Carbon Cycle and the Nitrogen Cycle Lesson Objectives Describe the short term cycling of carbon through the processes ...

18.14): Figure 18.14: ( 3 ) The amazing transformation that has happened here is changing energy from sunlight into chemical ene ...

natural gas. When this happens, it can take millions of years before the carbon becomes available again. Another way that carbon ...

Figure 18.16: The Keeling curve of atmospheric CO 2 concentrations measured at Mauna Loa Observatory. ( 4 ) Figure 18.17: ( 20 ) ...

The equation shows that when propane burns, it uses oxygen and the result is carbon dioxide and water. So each time we burn a fo ...

Figure 18.19: This diagram explains the role of greenhouse gases in our atmosphere. ( 24 ) global warming. As our Earth continue ...

As continental glacial ice melts, this will cause sea levels to rise, which will cause flooding of low lying coastal areas. That ...

Usable nitrogen is sometimes the factor that limits how many organisms can grow in an ecosystem. Modern agricultural practices i ...

carbon source An area of an ecosystem that emits more carbon dioxide than it absorbs. deforestation Cutting down and/or burning ...

abiotic factors are necessary. For example, too little water may cause land plants or animals to become dehydrated. Too much wat ...

1802, 3 billion in 1961, and 6.7 billion in 2008. As the human population continues to grow, different factors may emerge limiti ...