The Hardworking Minority: Assessing the Effects of Warming Soil on Acidobacteria

With global temperatures predicted to rise anywhere from 2 to 5 degrees Celsius as a result of climate change, there will be great changes to the global ecosystem. One area that may be particularly affected is the soil ecosystem, which is the focus of soil warming experiments in the Barre Woods of the Harvard Forest in Petersham, Massachusetts. In this experiment, soil plots are consistently warmed 5 degrees above the surrounding temperature, replicating conditions under a warmer climate. Knowledge of how these temperatures affect microbial life will allow predictions to be made as to what changes are likely to occur in the future, having an impact on biodiversity and biogeochemistry.

In 2017, soil core samples from the Barre Woods warming plot within the Harvard Forest underwent cell sorting and sequencing. Early analysis of metagenomic and metatranscriptomic data from the bacterial population revealed that one phylum was disproportionately present in both areas. Acidobacteria, while not the most represented phylum identified in these samples, showed significantly higher expression than their more abundant counterparts. These bacteria, typically found in soil, have been found in a wide range of environments, able to withstand extreme weather, acidity, and metal-contamination (Barns et al., 2007). The phylum itself has been established only recently, yet members are frequently found to have a great deal of sequence diversity, resulting in the creation of 26 sub-groups within the phylum (Barns et al., 2007).

Read Senior Thesis for additional information.