Future climate scenarios reduce antibiotic resistome-associated risk but enrich specific soil-borne pathogens

Understanding how climate change reshapes the soil resistome, i.e., the collection of antibiotic resistance genes (ARGs), is critical for environmental and public health. Using a representative six-year (2014-2019) metagenomic dataset from a long-term climate manipulation experiment, this study investigated the impacts of future climate scenarios on cropland and grassland soil resistomes. Both simulated climate warming (+0.6 °C) and extreme summers (+2.2 °C during 2018-2019) significantly reshaped soil resistome structures, reducing ARG richness by 4.4%-12.5% without significantly affecting total ARG abundance. Notably, simulated climate and extreme summers reduced the abundance of high-risk ARGs by 10.0% and 27.2%, respectively, and concomitantly lowered the estimated resistome-associated risk by 18.3% and 36.4%, primarily through selectively filtering their bacterial hosts (e.g., Pseudomonadota). At the same time, future climate scenarios confer a competitive advantage for specific soil-dwelling antibiotic-resistant phytopathogens (e.g., Rhodococcus fascians) and human pathogens (e.g., Mycobacterium spp.), potentially increasing their prevalence and public health relevance in soil ecosystems. These findings highlight the contrasting responses of soil resistomes and pathogen communities under future climate scenarios and underscore the importance of long-term monitoring of soil ARGs and pathogens in the context of on-going global change within a One Health framework.