The ecological and biogeographical concept of the species pool describes all species available that could potentially colonize and inhabit a focal habitat area. The concept lays emphasis on the fact that "local communities aren't closed systems, and that the species occupying any local site typically came from somewhere else", however, the species pool concept may suffer from the logical fallacy of composition. Most local communities, however, have just a fraction of its species pool present. It is derived from MacArthur and Wilson's Island Biogeography Theory that examines the factors that affect the species richness of isolated natural communities. It helps to understand the composition and richness of local communities and how they are influenced by biogeographic and evolutionary processes acting at large spatial and temporal scales. The absent portion of species pool—dark diversity—has been used to understand processes influencing local communities. Methods to estimate potential but absent species are developing.
It has been hypothesized that there might be a direct correlation between species richness and the size of the species pool for plant communities. Elsewhere, it was reported that "trade-offs and species pool structure (size and trait distribution) determines the shape of the plant productivity-diversity relationship.
- Howard V. Cornell; Susan P. Harrison (2014). "What Are Species Pools and When Are They Important?". Annual Review of Ecology, Evolution, and Systematics. 45 (1): 651. doi:10.1146/annurev-ecolsys-120213-091759.
- Zobel, M. (2016). "The species pool concept as a framework for studying patterns of plant diversity". Journal of Vegetation Science. 27: 8–18. doi:10.1111/jvs.12333.
- Jeremy Fox (2011). "Species pools and the fallacy of composition".
in any complete explanation of local community structure, the properties of the species pool won’t be exogenously determined. There’s nowhere on earth that’s external to community ecology; every population of every species is and always has been part of some local community somewhere
- Pärtel, M.; Szava-Kovats, R; Zobel, M. (2011). "Dark diversity: shedding light on absent species". Trends in Ecology and Evolution. 26 (3): 124–128. doi:10.1016/j.tree.2010.12.004. PMID 21195505.
- Eriksson, Ove (1993). "The Species-Pool Hypothesis and Plant Community Diversity". Oikos. 68 (2): 371–374. doi:10.2307/3544854. ISSN 0030-1299. JSTOR 3544854.
High species diversity is expected when the existing species-pool contains many species, and comparatively low species diversity will be found when the species-pool is small.
- Chalmandrier, Loïc; Albouy, Camille; Pellissier, Loïc (2017-11-13). "Species pool distributions along functional trade-offs shape plant productivity–diversity relationships". Scientific Reports. 7 (1): 15405. doi:10.1038/s41598-017-15334-4. ISSN 2045-2322. PMC 5684142. PMID 29133911.