Chloropicrin fumigation alters the soil phosphorus and the composition of the encoding alkaline phosphatase PhoD gene...

The transformation of phosphorus (P) compounds in soil depends largely on soil microbial communities and is sensitive to agricultural practices. However, the effects of soil fumigation on soil P, and microbes involved in P transformation, are unknown. Our results showed that chloropicrin (CP) fumigation significantly increased the available-P, Leached-P and active-P fractionation (inorganic P extracted from H₂O, NaHCO₃ and NaOH) in Shangdong and Miyun soils in the early stages of culture, while soil alkaline phosphatase (ALP) activity and phoD gene abundance decreased significantly. Leached-P in fumigated soil was positively correlated with increased active-P fractionation, indicating that it was an important source of soil Leached-P after fumigation. The changes in P-fractionation, Leached-P and ALP after fumigation were also significantly correlated with the composition of the microbial communities. CP fumigation briefly stimulated an increase in the abundance and diversity of phoD-harboring microbial communities and promoted the mineralization process of soil P. PICRUSt metagenomic analysis showed an increase in the relative abundance of microorganisms with involved in carbohydrate/lipid transport and metabolism functions after fumigation. These results suggest CP fumigation altered soil P transformation and phoD-harboring microbes that might lead to an increased risk of P enrichment in waterways.