Periphyton: an important regulator in optimizing soil phosphorus bioavailability in paddy fields

Environ Sci Pollut Res Int. 2016 Nov;23(21):21377-21384. doi: 10.1007/s11356-016-7363-0. Epub 2016 Aug 9.

Abstract

Periphyton is ubiquitous in paddy field, but its importance in influencing the bioavailability of phosphorus (P) in paddy soil has been rarely recognized. A paddy field was simulated in a greenhouse to investigate how periphyton influences P bioavailability in paddy soil. Results showed that periphyton colonizing on paddy soil greatly reduced P content in paddy floodwater but increased P bioavailability of paddy soil. Specifically, all the contents of water-soluble P (WSP), readily desorbable P (RDP), algal-available P (AAP), and NaHCO3-extractable P (Olsen-P) in paddy soil increased to an extent compared to the control (without periphyton) after fertilization. In particular, Olsen-P was the most increased P species, up to 216 mg kg-1 after fertilization, accounting for nearly 60 % of total phosphorus (TP) in soil. The paddy periphyton captured P up to 1.4 mg g-1 with Ca-P as the dominant P fraction and can be a potential crop fertilizer. These findings indicated that the presence of periphyton in paddy field benefited in improving P bioavailability for crops. This study provides valuable insights into the roles of periphyton in P bioavailability and migration in a paddy ecosystem and technical support for P regulation.

Keywords: Bioavailability; Paddy field; Periphyton; Phosphorus.

MeSH terms

  • Biological Availability
  • Ecosystem
  • Edible Grain / growth & development
  • Edible Grain / metabolism
  • Fertilizers / analysis*
  • Microalgae / growth & development*
  • Microalgae / metabolism
  • Oryza / growth & development*
  • Oryza / metabolism
  • Phosphorus / analysis*
  • Phosphorus / metabolism
  • Soil / chemistry*
  • Soil Pollutants / analysis*
  • Soil Pollutants / metabolism

Substances

  • Fertilizers
  • Soil
  • Soil Pollutants
  • Phosphorus