TY - JOUR
T1 - Habitat filtering determines the functional niche occupancy of plant communities worldwide
AU - Li, Yuanzhi
AU - Shipley, Bill
AU - Price, Jodi N.
AU - Dantas, Vinícius de L.
AU - Tamme, Riin
AU - Westoby, Mark
AU - Siefert, Andrew
AU - Schamp, Brandon S.
AU - Spasojevic, Marko J.
AU - Jung, Vincent
AU - Laughlin, Daniel C.
AU - Richardson, Sarah J.
AU - Bagousse-Pinguet, Yoann Le
AU - Schöb, Christian
AU - Gazol, Antonio
AU - Prentice, Honor C.
AU - Gross, Nicolas
AU - Overton, Jake
AU - Cianciaruso, Marcus V.
AU - Louault, Frédérique
AU - Kamiyama, Chiho
AU - Nakashizuka, Tohru
AU - Hikosaka, Kouki
AU - Sasaki, Takehiro
AU - Katabuchi, Masatoshi
AU - Frenette Dussault, Cédric
AU - Gaucherand, Stephanie
AU - Chen, Ning
AU - Vandewalle, Marie
AU - Batalha, Marco Antônio
PY - 2018/5
Y1 - 2018/5
N2 - How the patterns of niche occupancy vary from species-poor to species-rich communities is a fundamental question in ecology that has a central bearing on the processes that drive patterns of biodiversity. As species richness increases, habitat filtering should constrain the expansion of total niche volume, while limiting similarity should restrict the degree of niche overlap between species. Here, by explicitly incorporating intraspecific trait variability, we investigate the relationship between functional niche occupancy and species richness at the global scale. We assembled 21 datasets worldwide, spanning tropical to temperate biomes and consisting of 313 plant communities representing different growth forms. We quantified three key niche occupancy components (the total functional volume, the functional overlap between species and the average functional volume per species) for each community, related each component to species richness, and compared each component to the null expectations. As species richness increased, communities were more functionally diverse (an increase in total functional volume), and species overlapped more within the community (an increase in functional overlap) but did not more finely divide the functional space (no decline in average functional volume). Null model analyses provided evidence for habitat filtering (smaller total functional volume than expectation), but not for limiting similarity (larger functional overlap and larger average functional volume than expectation) as a process driving the pattern of functional niche occupancy. Synthesis. Habitat filtering is a widespread process driving the pattern of functional niche occupancy across plant communities and coexisting species tend to be more functionally similar rather than more functionally specialized. Our results indicate that including intraspecific trait variability will contribute to a better understanding of the processes driving patterns of functional niche occupancy.
AB - How the patterns of niche occupancy vary from species-poor to species-rich communities is a fundamental question in ecology that has a central bearing on the processes that drive patterns of biodiversity. As species richness increases, habitat filtering should constrain the expansion of total niche volume, while limiting similarity should restrict the degree of niche overlap between species. Here, by explicitly incorporating intraspecific trait variability, we investigate the relationship between functional niche occupancy and species richness at the global scale. We assembled 21 datasets worldwide, spanning tropical to temperate biomes and consisting of 313 plant communities representing different growth forms. We quantified three key niche occupancy components (the total functional volume, the functional overlap between species and the average functional volume per species) for each community, related each component to species richness, and compared each component to the null expectations. As species richness increased, communities were more functionally diverse (an increase in total functional volume), and species overlapped more within the community (an increase in functional overlap) but did not more finely divide the functional space (no decline in average functional volume). Null model analyses provided evidence for habitat filtering (smaller total functional volume than expectation), but not for limiting similarity (larger functional overlap and larger average functional volume than expectation) as a process driving the pattern of functional niche occupancy. Synthesis. Habitat filtering is a widespread process driving the pattern of functional niche occupancy across plant communities and coexisting species tend to be more functionally similar rather than more functionally specialized. Our results indicate that including intraspecific trait variability will contribute to a better understanding of the processes driving patterns of functional niche occupancy.
KW - community assembly
KW - determinants of plant community diversity and structure
KW - habitat filtering
KW - intraspecific trait variability
KW - limiting similarity
KW - niche occupancy
KW - species richness
UR - http://www.scopus.com/inward/record.url?scp=85042661231&partnerID=8YFLogxK
U2 - 10.1111/1365-2745.12802
DO - 10.1111/1365-2745.12802
M3 - Article
VL - 106
SP - 1001
EP - 1009
JO - Journal of Ecology
JF - Journal of Ecology
SN - 0022-0477
IS - 3
ER -