Effects of biochar on soil phosphorus availability, phosphatase activity, microbial functional genes and growth of Populus euphratica seedlings under different water conditions

This study aims to investigate the impact of biochar on various soil phosphorus transformations, phosphatase activity, microbial community structure, and Populus euphratica seedling growth rates across a range of soil moisture conditions. The results should be useful for managing soil phosphorus and making the most efficient use of biochar. The results showed that applying biochar significantly increased the soil accessible phosphorus content and the phosphorus content in both the aboveground and subsurface parts of P.euphratica seedlings. This is mainly attributable to biochar's direct and indirect effects on soil properties. Because biochar is naturally alkaline, it raises soil pH and reduces acid phosphatase activity in the soil around Populus euphratica seedlings in the rhizosphere. Perhaps the alkaline phosphatase level first showed an upward trend due to the combined impacts of water and biochar, and then it started to decline when the biochar addition was increased. Soil phosphorus functional genes phoC, phoD, gcd, and pqqc had an increase in copy number with biochar addition but not without treatment. Indirectly, the biochar treatment increased the soil's phosphorus availability by increasing the population of the phosphate-solubilizing bacteria Fusarium and Sphingomonas. Soil phosphorus availability is positively affected by biochar under various water conditions, according to research. This impact is due to chemical and microbiological mechanisms.