Soil initial bacterial diversity and nutrient availability determine the rate of xenobiotic biodegradation

Abstract

Understanding the relative importance of soil microbial diversity, plants and nutrient management is crucial to implement an effective bioremediation approach to xenobiotics-contaminated soils. To date, knowledge on the interactive effects of soil microbiome, plant and nutrient supply on influencing biodegradation potential of soils remains limited. In this study, we evaluated the individual and interactive effects of soil initial bacterial diversity, nutrient amendments (organic and inorganic) and plant presence on the biodegradation rate of pyrene, a polycyclic aromatic hydrocarbon. Initial bacterial diversity had a strong positive impact on soil biodegradation potential, with soil harbouring higher bacterial diversity showing ~2 times higher degradation rates than soils with lower bacterial diversity. Both organic and inorganic nutrient amendments consistently improved the degradation rate in lower diversity soils and had negative (inorganic) to neutral (organic) effect in higher diversity soils. Interestingly, plant presence/type did not show any significant effect on the degradation rate in most of the treatments. Structural equation modelling demonstrated that initial bacterial diversity had a prominent role in driving pyrene biodegradation rates. We provide novel evidence that suggests that soil initial microbial diversity, and nutrient amendments should be explicitly considered in the design and employment of bioremediation management strategies for restoring natural habitats disturbed by organic pollutants.

Microbial inoculants with higher capacity to colonize soils improved wheat drought tolerance

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How are microbes helping end hunger?

“…Healthy and fertile soils foster optimal conditions for the growth of crops, which is fundamental for the sustainability of the food supply chain, but many anthropogenic activities cause significant levels of soil degradation. To address the current soil crisis, different microbial tools have been developed to improve soil fertility, facilitate the decomposition of organic matter (Sáez‐Sandino et al., 2023 ), promote nutrient cycling, detoxify pollutants (Jayaramaiah et al., 2022 ) and support the overall resilience of the ecosystems. The importance of maintaining soil health and the positive influence of microorganisms in addressing this challenge has been discussed by Timmis and Ramos ( 2021 ), who advocate for the creation of a soil health system to proactively prevent soil loss.…”