Combined niche and neutral effects in a microbial wastewater treatment community.
It has long been assumed that differences in the relative abundance of taxa in microbial communities reflect differences in environmental conditions. Here we show that in the economically and environmentally important microbial communities in a wastewater treatment plant, the population dynamics are consistent with neutral community assembly, where chance and random immigration play an important and predictable role in shaping the communities. Using dynamic observations, we demonstrate a straightforward calibration of a purely neutral model and a parsimonious method to incorporate environmental influence on the reproduction (or birth) rate of individual taxa. The calibrated model parameters are biologically plausible, with the population turnover and diversity in the heterotrophic community being higher than for the ammonia oxidizing bacteria (AOB) and immigration into AOB community being relatively higher. When environmental factors were incorporated more of the variance in the observations could be explained but immigration and random reproduction and deaths remained the dominant driver in determining the relative abundance of the common taxa. Consequently we suggest that neutral community models should be the foundation of any description of an open biological system.
Ofiteru
Irina Dana
ID
School of Civil Engineering and Geosciences, Newcastle University, Newcastle upon Tyne NE1 7RU, United Kingdom.
Lunn
Mary
M
Curtis
Thomas P
TP
Wells
George F
GF
Criddle
Craig S
CS
Francis
Christopher A
CA
Sloan
William T
WT
D000465:Algorithms; D001419:Bacteria / Q000254:growth & development / Q000378:metabolism; D018533:Biomass; D004269:DNA, Bacterial / Q000032:analysis; D017753:Ecosystem; D008954:Models, Biological; D012150:Polymorphism, Restriction Fragment Length; D011157:Population Dynamics; D012722:Sewage / Q000382:microbiology*; D013997:Time Factors; D014871:Water Microbiology
D004269:DNA, Bacterial; D012722:Sewage