中国农业科学 ›› 2006, Vol. 39 ›› Issue (10): 2036-2041 .

• 土壤肥料·节水灌溉 • 上一篇    下一篇

土壤微生物量磷及碳磷比随加入无机磷量的变化

来璐,赵小蓉,林启美   

  1. 中国农业大学资源与环境学院
  • 收稿日期:2006-02-17 修回日期:1900-01-01 出版日期:2006-10-10 发布日期:2006-10-10
  • 通讯作者: 赵小蓉 赵小蓉 赵小蓉

The changes of soil microbial biomass P and C/P with adding different quantities of inorganic P

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  1. 中国农业大学资源与环境学院
  • Received:2006-02-17 Revised:1900-01-01 Online:2006-10-10 Published:2006-10-10

摘要: 土壤微生物量磷是植物磷素营养非常重要的来源,变化幅度很大,受多种因素影响。本研究向土壤中加入32P标记的KH2PO4,同时分别加入KH2PO4 0,10,20,40,80,240 mg P kg-1,再加入葡萄糖(5000 mg C kg-1土)和尿素(200 mg N kg-1土), 25℃下培养30d后,分别在2,6,12,18,30d采样测定土壤微生物量碳和微生物量磷,旨在了解土壤无机磷含量对土壤微生物量磷及碳磷比的影响。结果表明,加入的无机磷对土壤微生物量碳无显著的影响,但迅速被微生物吸收并富集在微生物量中。在培养的第2d,微生物量磷有一半以上来自加入的无机磷。并且,在一定范围内(Olsen-P约50 mg kg-1),土壤微生物量磷随土壤Olsen-P提高而增加,土壤Olsen-P每提高1个单位,土壤微生物量磷增加0.65个单位。微生物量碳磷比则相反,随土壤Olsen-P增加而降低。

关键词: 无机磷酸盐, 微生物量磷, 32p

Abstract: Soil microbial biomass P(SMBp) is an important resource of plant P nutrition. It changes widely and is influenced by soil conditions. Following additions of different quantities of KH232PO4 (0,10,20,40,80,240 mg P kg-1 soil) together with glucose (5000 mg C kg-1)and urea (200 mg N kg-1 soil), the soils were incubated at 25℃ for 30d. Soil microbial biomass C and P were determined at 2,6,12,18,30d. The purpose was to investigate the influence of inorganic P on soil microbial biomass P and C/P. The results showed that the added phosphates had no significant impact on soil microbial biomass C (SMBc). However, the added P was soon absorbed and accumulated by soil microbial biomass. At the second day, more than half of soil microbial biomass P was contributed by the added inorganic P. When soil Olsen-P was lower than 50 mg kg-1, soil microbial biomass P increased by about 0.65 mg kg-1 soil with increasing 1 mg kg-1 Olsen-P. In contrary, the ratio of soil microbial biomass C to P decreased with increasing soil Olsen-P.

Key words: Inorganic phosphate, Soil microbial biomass P, 32p