气候变化对土壤微生物多样性及其功能的影响

Effect of climate change on soil microbial diversity and function

以同时模拟未来大气CO2浓度和温度升高的田间开放式气候变化平台为依托,研究CO2浓度升高(CE)、升温(WA)以及两者同时升高(CW)对麦田土壤基础呼吸和微生物丰度、群落结构的影响.结果表明:CE对土壤基础呼吸没有影响,但是WA显著提高了土壤基础呼吸,在抽穗和成熟期分别增加了51.6%和38.5%.在分蘖期,土壤细菌和真菌丰度没有显著变化;而在抽穗和成熟期,CW和WA处理显著降低了真菌丰度,降低幅度分别达到32.1%~50.2%和32.0%~37.4%.通过对T-RFLP数据分析发现,CE、CW和WA处理对麦田土壤真菌和细菌群落结构没有显著影响,但是在一定程度上改变了古菌群落结构.与对照相比,CE处理真菌多样性提高了7.1%~8.2%,CW和WA处理真菌多样性分别降低了5.3%~13.5%和22.1%~33.6%;在分蘖和抽穗期,CE、CW和WA处理土壤细菌多样性比对照显著提高.

A climate change experiment was conducted to examine the effect of simulated elevated atmospheric carbondioxide(CO2)and temperature simultaneously on soil basal respiration and microbial community structure and abundancein an open field.Field treatments included the atmospheric CO2enrichment(CE),warming of canopy air(WA),interactive CO2enrichment and warming(CW)and the ambient control(CK)plots in the experiment platform.The resultsshown that CE had no effect on soil basal respiration,when soil basal respiration under WA treatment was increased by51.6%and38.5%at the heading and ripening stages,respectively.At the tillering stage,no change in the abundance ofbacteria or fungi was observed,however abundances of fungi were decreased by32.1%~50.2%and32.0%~37.4%at theheading and ripening stages,respectively.The analysis of T-RFLP profiles showed that CE,CW and WA treatment had noobvious effect on fungal and bacterial community structure,but changed the archaeal community structure in a certainextent.Comparing to the control,the diversity of fungi was increased by7.1%~8.2%during the wheat growth period butdecreased by5.3%~13.5%and22.1%~33.6%under CW and WA treatments,respectively;CE,CW and WA treatmentincreased bacterial diversity in wheat tillering and heading stages.