ABSTRACT
IPCC 5th Assessment Synthesis Report, Climate Change Beyond 2100, Irreversibility and Abrupt Changes, Section 2.4, IPCC (2014b).
Large regions of the world possess distinct fauna and flora, and have adapted to climate and other conditions in unique ways. The five main biome types are ocean/aquatic, desert, temperate forest and tropical rainforest, arctic tundra and tundra, and grassland biomes. Each type has sub-types-for example, grassland biomes comprise Prairies, Steppe, and Savanna. Biomes represent the basic unit for describing patterns of ecosystem form, process, and biodiversity. Biomes contain many (often similar) ecosystems, even though system sizes and their ranges can vary. An “ecosystem” is distinguished from a biome as an ecological system or community of living organisms (e.g., plants, animals and microorganisms) and non-living components (e.g., air, water, sun, mineral soil) that interact together, relying on nutrient, water and energy storage and flows (or fluxes) driven by global
biogeochemical cycles or pathways. These cycles recycle chemical substances as they move through the Earth system’s biotic (biosphere) and abiotic (lithosphere, atmosphere, and hydrosphere) compartments involving interrelated biological, geological and chemical factors.
