New lay summary wrote by Manuel Delgado-Baquerizo about his paper”Lack of functional redundancy in the relationship between microbial diversity and ecosystem functioning” published in the last issue (July) of Journal of Ecology. Happy reading! 

The shape of the relationship between microbial diversity and ecosystem function (BEF) remains unclear, which limits our capacity to assess the impact of microbial diversity depletion on key ecosystem functions for human well-being, such as CO₂ respiratory fluxes and toxin degradation. This knowledge is, moreover, key to predicting ecosystem functions under changing environment and formulating sustainable natural resource management and conservation policies. Here we conducted three independent microcosm experiments to assess the shape of the bacterial BEF relationship in multiple freshwater ecosystems from Australia and United Kingdom.

Our results provide solid evidence that unlike the positive but decelerating BEF relationship observed most frequently in plants and animals, most evaluated functional measurements were related to bacterial diversity in a non-redundant fashion (e.g. exponentially and/or linearly). Reduced bacterial diversity, even after accounting for biomass, caused a decrease in broad (i.e., CO₂ respiratory fluxes: conducted by many microbial communities) and specialized (toxin degradation: conducted by few microbial communities) functions in all cases.

Altogether, our results indicate that any loss of freshwater bacterial diversity can disproportionately promote high losses in ecosystem functioning; thus the consequences of declining microbial diversity on ecosystem functioning and human welfare have likely been considerably underestimated.

Manuel Delgado-Baquerizo
Hawkesbury Institute for the Environment
Western Sydney University
Australia