title: Mobilisation of inorganic phosphorus induced by rice straw in aggregates of a highly weathered upland soil.
abstract: BACKGROUND
  Microorganisms mediate biochemical transformations of phosphorus (P) in soil. This is of particular importance in highly weathered soils, which are usually P deficient. This study aimed to extend understanding of the separate role of bacteria and fungi in P transformations in aggregates of a highly weathered soil, by adding P-stripped rice straw and microorganism inhibitors to aggregates.
  
  
  RESULTS
  The amount of microbial biomass phosphorus (MB-P) in the treatment with rice straw alone increased by over two-fold during 16 days. At the end of 28 d, the amount of inorganic-P in Fe-, Al-, and Ca-bound fractions decreased, whilst the amount of organic-P increased substantially (P < 0.01). The effect of bacterial inhibitors (tetracycline and streptomycin sulphate) on P immobilisation was very small in the early phase (0-4 d), but became pronounced after 8 days, whilst the fungal inhibitor (actidione) initially caused a decrease in P immobilisation by about 60%, but had no effect after that.
  
  
  CONCLUSIONS
  Fungi and bacteria immobilise P in soil aggregates, with fungi being responsible initially. However, bacteria become dominant subsequently and immobilise P from the inorganic fractions.
authors.affiliation: Key Laboratory of Agro-ecological Processes in the Subtropical Region, Institute of Subtropical Agriculture, the Chinese Academy of Sciences, Changsha, China.
authors.forename: Longjun
authors.initials: L
authors.lastname: Ding
authors.forename: Jinshui
authors.initials: J
authors.lastname: Wu
authors.forename: Heai
authors.initials: H
authors.lastname: Xiao
authors.forename: Ping
authors.initials: P
authors.lastname: Zhou
authors.forename: J Keith
authors.initials: JK
authors.lastname: Syers
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology; D000935:Antifungal Agents / Q000494:pharmacology; D001419:Bacteria / Q000187:drug effects / Q000378:metabolism*; D003513:Cycloheximide / Q000494:pharmacology; D017753:Ecosystem; D005658:Fungi / Q000187:drug effects / Q000378:metabolism*; D008670:Metals / Q000737:chemistry; D012275:Oryza / Q000378:metabolism* / Q000382:microbiology; D010758:Phosphorus / Q000032:analysis / Q000378:metabolism*; D012987:Soil / Q000737:chemistry*; D012988:Soil Microbiology; D013307:Streptomycin / Q000494:pharmacology; D013752:Tetracycline / Q000494:pharmacology; D014887:Weather
chemical_list: D000900:Anti-Bacterial Agents; D000935:Antifungal Agents; D008670:Metals; D012987:Soil; D010758:Phosphorus; D003513:Cycloheximide; D013752:Tetracycline; D013307:Streptomycin