Future climate change enhances the complexity of plastisphere microbial co-occurrence networks, but does not significantly affect the community assembly.

Biobased and biodegradable plastics have been intensively used in agriculture as mulching films. They provide a distinctive habitat for soil microbes, yet much less is known about the community assembly and interactions of plastisphere microbiota in soils under future climate change. For the first time, we explored the relative importance of ecological processes and the co-occurrence networks of plastic-associated microbes under ambient and future climates. The drift primarily dominated the community assembly of bacteria and fungi after 180D and 328D incubation in both climate regimes. The neutral community model prediction indicated that the migration rate of the plastisphere community in the later decay phase was lower than that in the early decay phase, contributing to the generation of the specific niches. Furthermore, future climate promoted the complexity and modularity of plastic-associated microbial networks: more competition and cooperation were observed in bacteria (or inter-kingdom) and fungi under future climate conditions, respectively. Overall, our findings strengthened the understanding of ecological processes and interplay of plastisphere microbiota during plastic biodegradation in soils under ambient and future climate regimes.