title: Fire modifies the phylogenetic structure of soil bacterial co-occurrence networks.
abstract: Fire alters ecosystems by changing the composition and community structure of soil microbes. The phylogenetic structure of a community provides clues about its main assembling mechanisms. While environmental filtering tends to reduce the community phylogenetic diversity by selecting for functionally (and hence phylogenetically) similar species, processes like competitive exclusion by limiting similarity tend to increase it by preventing the coexistence of functionally (and phylogenetically) similar species. We used co-occurrence networks to detect co-presence (bacteria that co-occur) or exclusion (bacteria that do not co-occur) links indicative of the ecological interactions structuring the community. We propose that inspecting the phylogenetic structure of co-presence or exclusion links allows to detect the main processes simultaneously assembling the community. We monitored a soil bacterial community after an experimental fire and found that fire altered its composition, richness and phylogenetic diversity. Both co-presence and exclusion links were more phylogenetically related than expected by chance. We interpret such a phylogenetic clustering in co-presence links as a result of environmental filtering, while that in exclusion links reflects competitive exclusion by limiting similarity. This suggests that environmental filtering and limiting similarity operate simultaneously to assemble soil bacterial communities, widening the traditional view that only environmental filtering structures bacterial communities.
authors.affiliation: Centro de Investigaciones sobre Desertificación (CSIC-UVEG-GV), Carretera Moncada - Náquera, Km 4.5. E-46113, Moncada, Valencia, Spain.
authors.forename: Eduardo
authors.initials: E
authors.lastname: Pérez-Valera
authors.affiliation: Centro de Investigaciones sobre Desertificación (CSIC-UVEG-GV), Carretera Moncada - Náquera, Km 4.5. E-46113, Moncada, Valencia, Spain.
authors.forename: Marta
authors.initials: M
authors.lastname: Goberna
authors.affiliation: Department of Microbiology and Immunology, Rega Institute KU Leuven, Herestraat 49, Leuven, 3000, Belgium.|VIB Center for the Biology of Disease, VIB, Herestraat 49, Leuven, 3000, Belgium.|Department of Applied Biological Sciences (DBIT), Vrije Universiteit Brussel, Pleinlaan 2, Brussels, 1050, Belgium.
authors.forename: Karoline
authors.initials: K
authors.lastname: Faust
authors.affiliation: Department of Microbiology and Immunology, Rega Institute KU Leuven, Herestraat 49, Leuven, 3000, Belgium.|VIB Center for the Biology of Disease, VIB, Herestraat 49, Leuven, 3000, Belgium.|Department of Applied Biological Sciences (DBIT), Vrije Universiteit Brussel, Pleinlaan 2, Brussels, 1050, Belgium.
authors.forename: Jeroen
authors.initials: J
authors.lastname: Raes
authors.affiliation: Centro de Edafología y Biología Aplicada del Segura (CEBAS-CSIC), Campus Universitario de Espinardo, Espinardo, Murcia, E-30100, Spain.
authors.forename: Carlos
authors.initials: C
authors.lastname: García
authors.affiliation: Centro de Investigaciones sobre Desertificación (CSIC-UVEG-GV), Carretera Moncada - Náquera, Km 4.5. E-46113, Moncada, Valencia, Spain.
authors.forename: Miguel
authors.initials: M
authors.lastname: Verdú
mesh_terms: D001419:Bacteria / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D017753:Ecosystem; D004777:Environment; D010802:Phylogeny; D012987:Soil / Q000737:chemistry; D012988:Soil Microbiology
chemical_list: D012987:Soil