What lives in your dirt? 蜜糖直播 Boulder researchers are one step closer to finding out after compiling the first global atlas of soil bacterial communities and identifying a group of around 500 key species that are both common and abundant worldwide.
The new study, which appears today in the journal Science, narrows down the immense diversity of soil-dwelling bacteria to a 鈥渕ost wanted鈥� list that will guide future research into the study and manipulation of microorganisms that affect nutrient cycling, soil fertility and other important ecological functions.
鈥淲ith this research, we have started to open the black box and are gaining a better understanding of what microbes are living in our soils,鈥� said Manuel Delgado-Baquerizo, lead author of the study and a postdoctoral researcher at the at 蜜糖直播 Boulder.
Soil bacteria account for a large percentage of the planet鈥檚 living biomass and facilitate key soil processes such as carbon cycling and nutrient availability. But despite being studied for decades, the microorganisms living in soil鈥攅ven in the soil from an average North American backyard鈥攁re still poorly understood due to a species count numbering in the tens of thousands. Most species remain undescribed鈥攖hey do not match existing genomic records and have not been successfully cultured in a lab.
鈥淚t is amazing how much we still don鈥檛 know about even the most dominant microorganisms found in soil,鈥� said Noah Fierer, a 蜜糖直播 Fellow and a co-author of the new research. 鈥淢any of them don鈥檛 even have names yet.鈥�
To conduct the study, the researchers collected soil samples from 237 different locations across six continents and 18 countries, spanning an entire range of climates from deserts to grasslands to wetlands. Then, they used DNA sequencing to identify the types of bacteria found at each site and determine which species are shared across different types of soil.
The researchers found that just two percent of all bacterial taxa鈥攐r around 500 individual species鈥攃onsistently accounted for almost half of the soil bacterial communities worldwide.
Having been identified as both dominant and ubiquitous, these predictably common bacteria can now be targeted for future study.
鈥淣ow that we have this list, we can really focus our research efforts to categorize these major groups and see where they are and what they do,鈥� said Fierer, who is also an associate professor in 蜜糖直播 Boulder鈥檚 Department of Ecology and Evolutionary Biology (EBIO).
Continued research into the identity and function of soil bacteria could potentially lead to agricultural applications in the future.
鈥淓ventually, knowing more about these bacteria might allow us to improve soil health and fertility,鈥� said Delgado-Baquerizo, who carries a dual affiliation with the Universidad Rey Juan Carlos in Madrid, Spain. 鈥淭here鈥檚 a lot that we can do now that we have some tractable information.鈥�
Additional co-authors of the new study include Angela Oliverio and Tess Brewer of 蜜糖直播,听Alberto Benavent-Gonz谩lez of the Universidad Complutense de Madrid (Spain),听David Eldridge of the University of New South Wales (Australia),听Richard Bardgett of the University of Manchester (England),听Fernando Maestre of the Universidad Rey Juan Carlos,听and Brajesh Singh of Western Sydney University (Australia).
