采用室内强化模拟试验,研究了90d培养期内环境温度、土壤酸化和盐渍化3种典型设施环境条件对土壤易解吸磷(CaCl2-P)、有效r(Olsen-P)、微生物生物量磷(MB-P)以及微生物生物量碳磷比(MB-C/P)等活性磷的影响.结果显示,设施土壤MB-P含量随着环境温度的升高而显著上升;10℃培养结束时土壤CaCl2 P和Olsen P含量比4℃对照分别提高15.6％和2.7％.酸化促进设施土壤CaCl2-P及Olsen-P含量增加,而使土壤MB-P含量显著下降.培养结束时,与pH值为6.89的对照土壤相比,pH值为6.11和5.30的酸化处理土壤CaCl2-P含量分别提高26.7％和156.1％,其Olsen P含量分别增加14.1％和91.5％,其MB-P含量的降幅分别为13.3％和16.3％.盐化对土壤CaCl2-P和Olsen P含量的影响均不显著,土壤MB-P含量在12d后随盐化程度加重而显著下降.培养结束时,与土壤可溶性盐分为1.90g/kg的对照相比,可溶性盐分为3.05g/kg和5.01g/kg的土壤MBP含量分别下降42.2％和45.8％.另外,设施环境温度提升、酸化和盐化使土壤MB-C/P在40d后整体上均呈下降趋势.综上所述,在4～25℃范围内提升环境温度,减缓土壤pH值从6.89降至5.30的酸化过程,阻控土壤可溶性盐分从1.90g/kg升至5.01g/kg盐化进程,可保证设施土壤磷素供应,降低土壤磷素流失风险,增强微生物调控土壤有效磷库的潜力.%Labile phosphorus was considered as an important phosphorus pool in soil and played essential roles in soil phosphorus cycling.Based on a 90-day laboratory experiments,the effects of three greenhouse factors including environmental temperature,soil acidification and salinization on soil labile phosphorus were studied through the dynamics of readily desorption phosphorus (CaCl2-P),available phosphorus (Olsen-P),microbial biomass phosphorus (MB-P) and ratio of microbial biomass carbon to phosphorus (MB-C/P) in greenhouse soil.Results showed that MB-P content in the greenhouse soil was increased significantly with the rising of environmental temperature.Compared with the control (incubated under 4℃),the contents of CaCl2-P and Olsen-P in the greenhouse soil were increased by 15.6％ and 2.7％ under 10℃ at the end of incubation,respectively.Acidification of greenhouse soil promoted an increase in the contents of CaCl2-P and Olsen-P but a decrease in the MB-P content.Compared with the control (at pH 6.89) at the end of incubation,it was increased by 26.7％ and 156.1％ for CaCl2-P content,increased by 14.1％ and 91.5％ for Olsen-P content,but decreased by 13.3％ and 16.3％ for MB-P content in acidified soil at pH 6.11 and 5.30,respectively.Soil salinization showed no significant effect on the contents of CaCl2-P and Olsen-P in soil,whereas soil MB-P content was decreased dramatically with the aggravation of salinization after 12days of incubation.Compared with the control (1.90g/kg for soluble salt in soil),MB-P content in salinized soils with 3.05g/kg and 5.01g/kg of soluble salt was decreased by 42.2％ and 45.8％,respectively.In addition,the MB-C/P in greenhouse soil after 40-day incubation showed a general downtrend with the increment in environmental temperature,soil acidification and salinization.Therefore,it was concluded that management practices,such as increasing environmental temperature in a range of 4～25℃,slowing down the acidification process of soil pH value from 6.89 to 5.30,and controlling the salinization process of soil soluble salt from 1.90g/kg to 5.01g/kg,could keep supplying phosphorus in greenhouse soil to plants.These practices could also reduce the risk of phosphorus loss from soil,and enhance the potential of available phosphorus pool which were regulated by soil microorganisms.
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