Phod-harboring bacterial communities mediated slow and fast phosphorus transformation in alkaline soil of a Robinia pseudoacacia afforestation chronosequence

• Published in: Plant and soil Vol. 488; no. 1-2; pp. 517 - 532
• Main Authors: Wang, Ying, Yang, Lin, Zhang, Jiawen, Li, Yan, Kang, Haibin, Bai, Xiaoxiong, Cui, Yongxing, Zhang, Min, Dong, Liguo, Yu, Xuan
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01.07.2023; Springer; Springer Nature B.V
• Subjects: Abundance; Afforestation; Aging; Agricultural land; Agriculture; Alkaline phosphatase; Alkaline soils; Analysis; bacterial communities; Bioavailability; Biomedical and Life Sciences; Black locust; Carbon content; chronosequences; Community composition; Community structure; Ecology; equations; Forest ecosystems; forests; Fractions; genes; Genetic aspects; Growth; Life Sciences; Microorganisms; Multivariate statistical analysis; Organic carbon; Organic phosphorus; Phosphatase; Phosphates; Phosphorus; Phosphorus content; Plant Physiology; Plant Sciences; primary productivity; Research Article; Robinia pseudoacacia; Seedlings; Semi arid areas; Semiarid zones; Sodium hydroxide; soil organic carbon; Soil Science & Conservation; Soils; stand age; Stoichiometry; Terrestrial ecosystems; trees; Australia; China; Alkaline phosphatase; Phosphorus fractions; gene; SOC; Phosphorus mobilization
• ISSN: 0032-079X; 1573-5036
• DOI: 10.1007/s11104-023-05990-z

Background and aims Soil phosphorus (P) availability is a key factor determining primary productivity in forest ecosystems in arid and semiarid regions. Under P deficient conditions, phoD -harboring microorganisms secrete alkaline phosphatase, improving P bioavailability. However, their roles in aging plantations of leguminous trees is still unclear. Methods Soil samples were collected from 8-, 18-, and 30-year-old stands of a Robinia pseudoacacia afforestation of degraded agricultural land. Soil P fractions, alkaline phosphatase activity, phoD gene abundance, and bacterial community structure were determined. An experiment with P addition in pots with tree seedlings was set up to check for short-term P transformation processes. Results Soil inorganic P (Pi) and organic P (Po) in R. pseudoacacia afforestation stands mainly existed as stable Pi (NaOH-Pi) and moderately easily available Po (HCl-Po). The contents of all these soil P fractions except for HCl-Pi decreased with stand age, while alkaline phosphatase activity increased. Structural equation modelling (SEM) revealed that soil organic carbon (SOC), available phosphorus (AP) and labile-Po contents mediated the community composition, α diversity or abundance of phoD genes, thereby affecting alkaline phosphatase activity. SOC showed the strongest positive effect on alkaline phosphatase activity. The P addition experiment suggests that alkaline phosphatase activity was mainly regulated via soil C:P stoichiometry. Conclusion SOC appears to be an important regulator of Po turnover in P deficient soils via phoD gene-harboring microbes.