High-emission socioeconomic pathways threaten phoD-harboring bacterial communities in cold ecosystems

Abstract Alkaline phosphatase gene (phoD) harboring microbial communities drive organic phosphorus (P) mineralization, regulating plant P availability and ecosystem productivity. However, their global distribution pattern, key environmental drivers, and responses to climate change remain poorly understood. Here, we conducted a meta-analysis of phoD amplicon sequences from 3,175 samples spanning diverse ecosystems worldwide, revealing higher diversity in colder and more arid ecosystems. Climate (temperature, humidity) and pH emerged as key determinants, structuring distinct ecological clusters. Random forest models predicted that under high-emission scenarios (SSP585, + 3.8 to + 8.6°C increment of air temperature), warm-, humid-, and alkaline-associated clusters will expand, while cold-adapted clusters may decline by 84.3%, particularly in vulnerable cold grassland and alpine desert soils. Comparative genomic analysis further revealed higher P-starvation response and inorganic P-solubilization gene frequencies in warm-adapted taxa. These findings provide new insights into the ecological adaptation of phoD-harboring communities and highlight potential disruptions to microbial P cycling under climate change, emphasizing the need for conservation strategies to protect cold-adapted functional microbial communities.