中国环境科学2011,31(9)：1541~1547ChinaEnvironmentalScience模拟酸雨对北亚热带天然次生林土壤呼吸的影响张勇,王连喜,陈书涛*,胡正华,沈小帅,史艳姝(南京信息工程大学环境科学与工程学院,江苏南京210044)摘要：于2009年3月～2010年1月在南京市郊龙王山北亚热带天然次生林进行模拟酸雨试验,以便携式土壤CO2通量观测仪对不同酸雨强度处理下的林地土壤呼吸速率进行原位测定,研究酸雨对森林土壤呼吸的影响.结果表明,在本试验阶段,4个酸雨强度处理CK(pH值6.4,去离子水)、T1(pH值4.5)、T2(pH值3.5)、T3(pH值2.5)的平均土壤呼吸速率分别为(3.20±0.21)、(3.34±0.30)、(3.51±0.06)、(2.99±0.23)μmol/(m2·s),酸雨各处理的土壤呼吸季节变化规律显著.由于森林植被生长期季节变化明显,将其分为非生长季1(2~4月)、生长季(5~10月)、非生长季2(11月~次年1月)3个阶段.配对t检验分析各阶段土壤呼吸速率的结果表明,在非生长季1,模拟酸雨未抑制土壤呼吸作用,T1和T2酸雨处理反而促进了土壤呼吸作用;在生长季,高强度模拟酸雨T3显著抑制了土壤呼吸作用;在非生长季2,也出现了模拟酸雨促进土壤呼吸作用的现象;对于整个观测阶段而言,低强度模拟酸雨处理未显著改变北亚热带天然次生林的土壤呼吸,仅高强度模拟酸雨T3显著抑制了土壤呼吸作用.不同酸雨强度处理下的土壤呼吸速率与土壤温度的指数回归关系均达显著水平(P<0.01),CK、T1、T2、T3处理的Q10值分别为3.04,2.73,2.83,2.51,模拟酸雨处理降低了北亚热带天然次生林土壤呼吸的温度敏感性.关键词：模拟酸雨；土壤呼吸；次生林；Q10值中图分类号：X517文献标识码：A文章编号：1000-6923(2011)09-1541-07Effectsofsimulatedacidrainonsoilrespirationinanorthernsubtropicalsecondaryforest.ZHANGYong,WANGLian-xi,CHENShu-tao*,HUZheng-hua,SHENXiao-shuai,SHIYan-shu(SchoolofEnvironmentalScienceandEngineering,NanjingUniversityofInformationScienceandTechnology,Nanjing210044,China).ChinaEnvironmentalScience,2011,31(9)：1541~1547Abstract：Inordertoinvestigatetheeffectsofacidrainonforestsoilrespiration,asimulatedacidrainexperimentwasconductedinanorthernsubtropicalsecondaryforestfromMarch2009toJanuary2010.AcidraintreatmentsincludedCK(pH6.4,deionizedwater),T1(pH4.5),T2(pH3.5)andT3(pH2.5).AportablesoilCO2fluxessystemwasusedtomeasuresoilrespirationrates.Resultsshowedthatsoilrespirationamongalltreatmentshadsignificantseasonalvariationpatterns.MeansoilrespirationratesforCK,T1,T2andT3treatmentswere(3.20±0.21),(3.34±0.30),(3.51±0.06),(2.99±0.23)μmol/(m2·s),respectively.Theexperimentalperiodwasdividedintothreeparts,whichwerenon-growthperiod1(fromFebruary,2009toApril,2009),growthperiod(fromMary,2009toOctober,2009),non-growthperiod2(fromNovember,2009toJanuary,2010),respectively.Apairedt-testanalysisshowedthatsimulatedacidraindidnotinhibitsoilrespiration,T1andT2tendedtopromotesoilrespirationinthenon-growthperiod1;T3significantlyinhibitedsoilrespirationduringgrowthperiod;simulatedacidrainalsopromotedsoilrespirationduringthenon-growthperiod2.OnlyT3significantlyinhibitedsoilrespirationduringthewholeexperimentalperiod.Duringthewholeexperimentalperiod,soilrespirationshowedanexponentialrelationshipwithsoiltemperatureforeachofthetreatment.TheQ10(therespiratoryfluxatonetemperatureoverthefluxatatemperature10ºClower)valueswere3.04,2.73,2.83and2.51forCK,T1,T2,T3treatments,respectively.Simulatedacidrainsignificantlyreducedthetemperaturesensitivityofsoilrespirationinthenorthernsubtropicalsecondaryforest.Keywords：simulatedacidrain；soilrespiration；secondaryforest；Q10value全球变暖和酸雨已经成为影响人类生存和发展的全球性环境问题[1-2].我国受酸雨危害地区的面积已超过国土面积的40%[3],其中亚热带地区酸雨...
