季节性雪被变化对森林凋落物分解及土壤氮动态的影响
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摘要
全球气候变化引发的雪被格局变化将深刻影响植被的凋落物分解、陆地生态系统的土壤养分循环等过程.森林是陆地生态系统的主体,在全球生物地球化学循环中起着不可替代的作用.本研究综述了季节性雪被变化对森林凋落物分解及土壤氮动态的影响.全球气候变化情景下季节性雪被表现出因地域而异的增加或减少的变化格局,一方面通过改变环境温湿度、凋落物质量、分解者动态等直接影响分解过程,另一方面通过改变森林群落结构、植被物候、土壤养分等间接地作用于凋落物分解.同时,季节性雪被通过影响氮富集作用、雪被下土壤温湿度、冻融循环、森林群落、雪下动物和微生物等相关因子而改变森林土壤氮循环.本领域未来应开展的研究是:1)全面考虑全球气候变化情景下季节性雪被格局的变异性,开展不同季节性雪被格局变化的模拟研究;2)开展季节性雪被融雪水淋溶作用对森林凋落物分解和土壤氮动态的影响研究;3)阐明不同生态系统和气候带中季节性雪被格局变化对森林凋落物分解过程和土壤氮动态的驱动机制研究;4)量化季节性雪被变化对森林凋落物分解和土壤氮动态在雪被覆盖期的瞬时影响和无雪期的延续影响,为阐明和模型预测陆地生态系统生物地球化学循环对全球气候变化的响应提供理论基础和数据支持.
Changes in snow-cover patterns induced by global climate change profoundly influence ecological processes in terrestrial ecosystems, including litter decomposition and soil nutrient cycling. Forest,a major terrestrial ecosystem,plays a crucial role in global biogeochemical cycling.Here,we reviewed the effects of changes in seasonal snow-cover on litter decomposition and soil nitrogen( N) cycling in forests. Global climate change would result in increasing or decreasing seasonal snow-cover depending on local conditions,with direct and indirect effects on forest litter decomposition. The changes in seasonal snow-cover would directly affect decomposition process by changing environmental temperature and moisture,litter quality,and decomposer dynamics,and would indirectly influence decomposition via altering community structure,vegetation phenology,and soil nutrients. Meanwhile,the changes in seasonal snow-cover would modify forest soil N dynamics through changing N enrichment,soil temperature and moisture,freeze-thaw cycle,forest community,subnivean fauna and microorganisms. Further studies in this field should focus on: 1)employing experiments with divergent protocols to simulate diverse changing patterns of seasonal snow-cover under the global climate change scenarios; 2) the effects of the seasonal snowmelt leaching on forest litter decomposition and soil N dynamics; 3) elucidating mechanisms underlying forest litter decomposition and soil N dynamics driven by changes in seasonal snow-cover patterns in different ecosystems and climate zones; and 4) quantifying the instantaneous and prolonged effects of changes in seasonal snow-cover on forest litter decomposition and soil N dynamics in the snowcovered and snow-free seasons,respectively. These studies will provide theoretical basis and solid data support for the understanding and model-prediction of the responses of the biogeochemical cycle in terrestrial ecosystems to global climate change.
Changes in snow-cover patterns induced by global climate change profoundly influence ecological processes in terrestrial ecosystems, including litter decomposition and soil nutrient cycling. Forest,a major terrestrial ecosystem,plays a crucial role in global biogeochemical cycling.Here,we reviewed the effects of changes in seasonal snow-cover on litter decomposition and soil nitrogen( N) cycling in forests. Global climate change would result in increasing or decreasing seasonal snow-cover depending on local conditions,with direct and indirect effects on forest litter decomposition. The changes in seasonal snow-cover would directly affect decomposition process by changing environmental temperature and moisture,litter quality,and decomposer dynamics,and would indirectly influence decomposition via altering community structure,vegetation phenology,and soil nutrients. Meanwhile,the changes in seasonal snow-cover would modify forest soil N dynamics through changing N enrichment,soil temperature and moisture,freeze-thaw cycle,forest community,subnivean fauna and microorganisms. Further studies in this field should focus on: 1)employing experiments with divergent protocols to simulate diverse changing patterns of seasonal snow-cover under the global climate change scenarios; 2) the effects of the seasonal snowmelt leaching on forest litter decomposition and soil N dynamics; 3) elucidating mechanisms underlying forest litter decomposition and soil N dynamics driven by changes in seasonal snow-cover patterns in different ecosystems and climate zones; and 4) quantifying the instantaneous and prolonged effects of changes in seasonal snow-cover on forest litter decomposition and soil N dynamics in the snowcovered and snow-free seasons,respectively. These studies will provide theoretical basis and solid data support for the understanding and model-prediction of the responses of the biogeochemical cycle in terrestrial ecosystems to global climate change.
引文
[1]Edwards AC,Scalenghe R,Freppaz M.Changes in the seasonal snow cover of alpine regions and its effect on soil processes:A review.Quaternary International,2007,162:172-181
[2]Walther GR,Post E,Convey P,et al.Ecological responses to recent climate change.Nature,2002,416:389-395
[3]Lundquist JD,Neiman PJ,Martner B,et al.Rain versus snow in the Sierra Nevada,California:Comparing Doppler profiling radar and surface observations of melting level.Journal of Hydrometeorology,2008,9:194-211
[4]Vankoughnett MR,Henry HA.Soil freezing and N deposition:Transient vs.multi-year effects on plant productivity and relative species abundance.New Phytologist,2014,202:1277-1285
[5]Hayhoe K,Wake CP,Huntington TG,et al.Past and future changes in climate and hydrological indicators in the US Northeast.Climate Dynamics,2007,28:381-407
[6]Li P-J(李培基).Preliminary evaluation of seasonal snow resources in China.Acta Geographica Sinica(地理学报),1988,43(2):108-119(in Chinese)
[7]Venalainen A,Tuomenvirta H,Heikinheimo M,et al.Impact of climate change on soil frost under snow cover in a forested landscape.Climate Research,2001,17:63-72
[8]Uhlmann B,Goyette S,Beniston M.Sensitivity analysis of snow patterns in Swiss ski resorts to shifts in temperature,precipitation and humidity under conditions of climate change.International Journal of Climatology,2009,29:1048-1055
[9]Mote PW,Hamlet AF,Clark MP,et al.Declining mountain snowpack in western north America.Bulletin of the American Meteorological Society,2005,86:39-49
[10]Brooks PD,Grogan P,Templer PH,et al.Carbon and nitrogen cycling in snow-covered environments.Geography Compass,2011,5:682-699
[11]Qin DH,Liu SY,Li PJ.Snow cover distribution,variability,and response to climate change in western China.Journal of Climate,2006,19:1820-1833
[12]Beniston M,Keller F,Goyette S.Snow pack in the Swiss Alps under changing climatic conditions:An empirical approach for climate impacts studies.Theoretical and Applied Climatology,2003,74:19-31
[13]Wang G-X(王根绪),Li Q(李琪),Cheng G-D(程国栋),et al.Climate change and its impact on the eco-environment in the source regions of the Yangtze and Yellow Rivers in recent 40 years.Journal of Glaciology and Geocryology(冰川冻土),2001,23(4):346-352(in Chinese)
[14]Kreyling J,Haei M,Laudon H.Absence of snow cover reduces understory plant cover and alters plant community composition in boreal forests.Oecologia,2012,168:577-587
[15]Robroek BJ,Heijboer A,Jassey VE,et al.Snow cover manipulation effects on microbial community structure and soil chemistry in a mountain bog.Plant and Soil,2013,369:151-164
[16]Jusselme MD,Saccone P,Zinger L,et al.Variations in snow depth modify N-related soil microbial abundances and functioning during winter in subalpine grassland.Soil Biology and Biochemistry,2016,92:27-37
[17]Berg B.Litter decomposition and organic matter turnover in northern forest soils.Forest Ecology and Management,2000,133:13-22
[18]Schimel JP,Bennett J.Nitrogen mineralization:Challenges of a changing paradigm.Ecology,2004,85:591-602
[19]Jones HG.Snow Ecology:An Interdisciplinary Examination of Snow-Covered Ecosystems.Cambridge:Cambridge University Press,2001
[20]Bokhorst S,Metcalfe DB,Wardle DA.Reduction in snow depth negatively affects decomposers but impact on decomposition rates is substrate dependent.Soil Biology and Biochemistry,2013,62:157-164
[21]Buckeridge KM,Grogan P.Deepened snow alters soil microbial nutrient limitations in arctic birch hummock tundra.Applied Soil Ecology,2008,39:210-222
[22]Neff JC,Holland EA,Dentener FJ,et al.The origin,composition and rates of organic nitrogen deposition:Amissing piece of the nitrogen cycle?Biogeochemistry,2002,57:99-136
[23]Brooks PD,Williams MW.Snowpack controls on nitrogen cycling and export in seasonally snow-covered catchments.Hydrological Processes,1999,13:2177-2190
[24]Brown RD,Mote PW.The response of northern hemisphere snow cover to a changing climate.Journal of Climate,2009,22:2124-2145
[25]IPCC.Climate Change 2007:The Physical Science Basis.Cambridge:Cambridge University Press,2007
[26]Aerts R,Callaghan TV,Dorrepaal E,et al.Seasonal climate manipulations result in species-specific changes in leaf nutrient levels and isotopic composition in a subarctic bog.Functional Ecology,2009,23:680-688
[27]Uchida M,Mo W,Nakatsubo T,et al.Microbial activity and litter decomposition under snow cover in a cooltemperate broad-leaved deciduous forest.Agricultural and Forest Meteorology,2005,134:102-109
[28]Baptist F,Yoccoz NG,Choler P.Direct and indirect control by snow cover over decomposition in alpine tundra along a snowmelt gradient.Plant and Soil,2010,328:397-410
[29]Aerts R,Callaghan TV,Dorrepaal E,et al.Seasonal climate manipulations have only minor effects on litter decomposition rates and N dynamics but strong effects on litter P dynamics of sub-arctic bog species.Oecologia,2012,170:809-819
[30]Christenson LM,Mitchell MJ,Groffman PM,et al.Winter climate change implications for decomposition in northeastern forests:Comparisons of sugar maple litter with herbivore fecal inputs.Global Change Biology,2010,16:2589-2601
[31]Hu X(胡霞),Wu N(吴宁),Wu Y(吴彦),et al.Effects of snow cover on the decomposition and nutrient dynamics of Sibiraea angustata leaf litter in western Sichuan Plateau,Southwest China.Chinese Journal of Applied Ecology(应用生态学报),2012,23(5):1226-1232(in Chinese)
[32]Huang C,Wu F,Yang W,et al.Effects of snow thickness on the abundance of archaeal and bacterial amo Agenes and gene transcripts during dwarf bamboo litter decomposition in an alpine forest on the eastern Tibetan Plateau.Russian Journal of Ecology,2016,47:419-429
[33]Li H,Wu F,Yang W,et al.Effects of forest gaps on litter lignin and cellulose dynamics vary seasonally in an alpine forest.Forests,2016,7:27,doi:10.3390/f7020027
[34]Ni X,Yang W,Li H,et al.The responses of early foliar litter humification to reduced snow cover during winter in an alpine forest.Canadian Journal of Soil Science,2014,94:453-461
[35]Wu Q-G(吴庆贵),Wu F-Z(吴福忠),Tan B(谭波),et al.Effects of gap sizes on foliar litter decomposition in alpine forests.Acta Ecologica Sinica(生态学报),2016,36(12):3537-3545(in Chinese)
[36]Wu Q-Q(武启骞),Wu F-Z(吴福忠),Yang W-Q(杨万勤),et al.Effect of seasonal snow cover on litter decomposition in alpine forest.Chinese Journal of Plant Ecology(植物生态学报),2013,37(4):296-305(in Chinese)
[37]Shibata H,Hasegawa Y,Watanabe T,et al.Impact of snowpack decrease on net nitrogen mineralization and nitrification in forest soil of northern Japan.Biogeochemistry,2013,116:69-82
[38]Gavazov KS.Dynamics of alpine plant litter decomposition in a changing climate.Plant and Soil,2010,337:19-32
[39]Wipf S,Rixen C.A review of snow manipulation experiments in Arctic and alpine tundra ecosystems.Polar Research,2010,29:95-109
[40]Wu FZ,Yang WQ,Zhang J,et al.Litter decomposition in two subalpine forests during the freeze-thaw season.Acta Oecologica,2010,36:135-140
[41]Groffman PM,Driscoll CT,Fahey TJ,et al.Effects of mild winter freezing on soil nitrogen and carbon dynamics in a northern hardwood forest.Biogeochemistry,2001,56:191-213
[42]He J(何洁),Jiang X-M(蒋先敏),Yang W-Q(杨万勤),et al.Effects of snow patches on the release of N and P during foliar litter decomposition in an alpine forest of western Sichuan,China.Chinese Journal of Applied Ecology(应用生态学报),2014,25(8):2158-2166(in Chinese)
[43]Lemma B,Nilsson I,Kleja DB,et al.Decomposition and substrate quality of leaf litters and fine roots from three exotic plantations and a native forest in the southwestern highlands of Ethiopia.Soil Biology and Biochemistry,2007,39:2317-2328
[44]Bardgett R.The Biology of Soil:A Community and Ecosystem Approach.Oxford:Oxford University Press,2005
[45]Hagvar S,Hagvar EB.Invertebrate activity under snow in a South-Norwegian spruce forest.Soil Organisms,2011,83:187-209
[46]Holmstrup M,Hedlund K,Boriss H.Drought acclimation and lipid composition in Folsomia candida:Implications for cold shock,heat shock and acute desiccation stress.Journal of Insect Physiology,2002,48:961-970
[47]Pesaro M,Widmer F,Nicollier G,et al.Effects of freeze-thaw stress during soil storage on microbial communities and methidathion degradation.Soil Biology and Biochemistry,2003,35:1049-1061
[48]Schmidt SK,Lipson DA.Microbial growth under the snow:Implications for nutrient and allelochemical availability in temperate soils.Plant and Soil,2004,259:1-7
[49]Wu Q,Wu F,Yang W,et al.Foliar litter nitrogen dynamics as affected by forest gap in the alpine forest of eastern Tibet Plateau.PLo S One,2014,9(5):e97112
[50]Bell TH,Klironomos JN,Henry HA.Seasonal responses of extracellular enzyme activity and microbial biomass to warming and nitrogen addition.Soil Science Society of America Journal,2010,74:820-828
[51]Wu Y(吴彦).Effects of seasonal snow cover on plant community.Journal of Mountain Science(山地学报),2005,23(5):550-556(in Chinese)
[52]Wahren CHA,Walker MD,Bret-Harte MS.Vegetation responses in Alaskan arctic tundra after 8 years of a summer warming and winter snow manipulation experiment.Global Change Biology,2005,11:537-552
[53]Groffman PM,Driscoll CT,Fahey TJ,et al.Colder soils in a warmer world:A snow manipulation study in a northern hardwood forest ecosystem.Biogeochemistry,2001,56:135-150
[54]Tierney GL,Fahey TJ,Groffman PM,et al.Soil freezing alters fine root dynamics in a northern hardwood forest.Biogeochemistry,2001,56:175-190
[55]Waker MD,Ingersoll RC,Webber PJ.Effects of interannual climate variation on phenology and growth of two alpine forbs.Ecology,1995,76:1067-1083
[56]Davies TD,Tranter M,Jickells TD,et al.Heavilycontaminated snowfalls in the remote Scottish Highlands:A consequence of regional-scale mixing and transport.Atmospheric Environment Part A General Topics,1992,26:95-112
[57]Guan J-Q(关俊祺),Cai T-J(蔡体久),Man X-L(满秀玲).Characteristics of snowpack chemistry in different type plantations of Xiaoxing’an Mountains,northeastern China.Journal of Beijing Forestry University(北京林业大学学报),2013,35(4):41-46(in Chinese)
[58]Buckeridge KM,Cen YP,Layzell DB,et al.Soil biogeochemistry during the early spring in low arctic mesic tundra and the impacts of deepened snow and enhanced nitrogen availability.Biogeochemistry,2010,99:127-141
[59]Buckeridge KM,Grogan P.Deepened snow increases late thaw biogeochemical pulses in mesic low arctic tundra.Biogeochemistry,2010,101:105-121
[60]Fitzhugh RD,Driscoll CT,Groffman PM,et al.Effects of soil freezing disturbance on soil solution nitrogen,phosphorus,and carbon chemistry in a northern hardwood ecosystem.Biogeochemistry,2001,56:215-238
[61]Freppaz M,Celi L,Marchelli M,et al.Snow removal and its influence on temperature and N dynamics in alpine soils(Vallee d’Aoste,northwest Italy).Journal of Plant Nutrition and Soil Science,2008,171:672-680
[62]Groffman PM,Hardy JP,Nolan S,et al.Snow depth,soil frost and nutrient loss in a northern hardwood forest.Hydrological Processes,1999,13:2275-2286
[63]Groffman PM,Hardy JP,Driscoll CT,et al.Snow depth,soil freezing,and fluxes of carbon dioxide,nitrous oxide and methane in a northern hardwood forest.Global Change Biology,2006,12:1748-1760
[64]Groffman PM,Hardy JP,Fashu-Kanu S,et al.Snow depth,soil freezing and nitrogen cycling in a northern hardwood forest landscape.Biogeochemistry,2011,102:223-238
[65]Hentschel K,Borken W,Zuber T,et al.Effects of soil frost on nitrogen net mineralization,soil solution chemistry and seepage losses in a temperate forest soil.Global Change Biology,2009,15:825-836
[66]Pilon CE,C8téB,Fyles JW.Effect of snow removal on leaf water potential,soil moisture,leaf and soil nutrient status and leaf peroxidase activity of sugar maple.Plant and Soil,1994,162:81-88
[67]Steinweg JM,Fisk MC,Mc Alexander B,et al.Experimental snowpack reduction alters organic matter and net N mineralization potential of soil macroaggregates in a northern hardwood forest.Biology and Fertility of Soils,2008,45:1-10
[68]Sulkava P,Huhta V.Effects of hard frost and freezethaw cycles on decomposer communities and N mineralisation in boreal forest soil.Applied Soil Ecology,2003,22:225-239
[69]Tan B,Wu FZ,Yang WQ,et al.Snow removal alters soil microbial biomass and enzyme activity in a Tibetan alpine forest.Applied Soil Ecology,2014,76:34-41
[70]Viglietti D,Freppaz M,Filippa G,et al.Soil C and Nresponse to changes in winter precipitation in a subalpine forest ecosystem,NW Italy.Hydrological Processes,2014,28:5309-5321
[71]Jones HG.The ecology of snow-covered systems:A brief overview of nutrient cycling and life in the cold.Hydrological Processes,1999,13:2135-2147
[72]Williams MW,Bales RC,Brown AD,et al.Fluxes and transformations of nitrogen in a high-elevation catchment,Sierra Nevada.Biogeochemistry,1995,28:1-31
[73]Williams MW,Tonnessen KA.Critical loads for inorganic nitrogen deposition in the Colorado Front Range,USA.Ecological Applications,2000,10:1648-1665
[74]De Marco J,Mack MC,Bret-Harte MS.The effects of snow,soil microenvironment,and soil organic matter quality on N availability in three Alaskan arctic plant communities.Ecosystems,2011,14:804-817
[75]Schimel JP,Bilbrough C,Welker JM.Increased snow depth affects microbial activity and nitrogen mineralization in two Arctic tundra communities.Soil Biology and Biochemistry,2004,36:217-227
[76]Brooks PD,Schmidt SK,Williams MW.Winter production of CO2and N2O from alpine tundra:Environmental controls and relationship to inter-system C and N fluxes.Oecologia,1997,110:403-413
[77]Schürmann A,Mohn J,Bachofen R.N2O emissions from snow covered soils in the Swiss Alps.Tellus B,2002,54:134-142
[78]Teepe R,Brumme R,Beese F.Nitrous oxide from frozen soils under agriculture,fallow and forest.Soil Biology and Biochemistry,2000,32:1807-1810
[79]Maljanen M,Alm J,Martikainen PJ,et al.Prolongation of soil frost resulting from reduced snow cover increases nitrous oxide emissions from boreal forest soil.Boreal Environment Research,2010,15:34-42
[80]Koponen HT,Jaakkola T,Keinanen-Toivola MM,et al.Microbial communities,biomass,and activities in soils as affected by freeze thaw cycles.Soil Biology and Biochemistry,2006,38:1861-1871
[81]Wang H-Y(王怀玉),Yang W-Q(杨万勤).Effects of seasonal freeze-thaw cycles on quantity of soil microbes in the subalpine fir forest.Scientia Silvae Sinicae(林业科学),2012,48(5):88-94(in Chinese)
[82]Larsen KS,Jonasson S,Michelsen A.Repeated freezethaw cycles and their effects on biological processes in two arctic ecosystem types.Applied Soil Ecology,2002,21:187-195
[83]Sjursen H,Michelsen A,Holmstrup M.Effects of freeze-thaw cycles on microarthropods and nutrient availability in a sub-Arctic soil.Applied Soil Ecology,2005,28:79-93
[84]Wang L-Q(王丽芹),Qi Y-C(齐玉春),Dong Y-S(董云社),et al.Effects and mechanism of freezethawing cycles on key processes of nitrogen cycle in terrestrial ecosystem.Chinese Journal of Applied Ecology(应用生态学报),2015,26(11):3532-3544(in Chinese)
[85]Freppaz M,Williams BL,Edwards AC,et al.Simulating soil freeze/thaw cycles typical of winter alpine conditions:Implications for N and P availability.Applied Soil Ecology,2007,35:247-255
[86]Li S-N(李胜男),Fan Z-P(范志平),Li F-Y(李法云),et al.Responses of soil nitrogen transformation process to freezing-thawing cycle in a riparian zone under three different vegetation types.Chinese Journal of Ecology(生态学杂志),2013,32(6):1391-1398(in Chinese)
[87]Deluca TH,Keeney DR,Mccarty GW.Effect of freezethaw events on mineralization of soil nitrogen.Biology and Fertility of Soils,1992,14:116-120
[88]Tao N(陶娜),Zhang X-Y(张馨月),Zeng H(曾辉),et al.Seasonal characteristics of soil CO2efflux and carbon and nitrogen cycling induced by microorganisms in snow-covered and frozen soil system.Microbiology China(微生物学通报),2013,40(1):146-157(in Chinese)
[89]Yanai Y,Toyota K,Okazaki M.Response of denitrifying communities to successive soil freeze-thaw cycles.Biology and Fertility of Soils,2007,44:113-119
[90]Teepe R,Brumme R,Beese F.Nitrous oxide emissions from soil during freezing and thawing periods.Soil Biology and Biochemistry,2001,33:1269-1275
[91]Liu L(刘琳),Wu Y(吴彦),He Y-X(何奕忻),et al.Effects of seasonal snow cover on soil nitrogen transformation in alpine ecosystem:A review.Chinese Journal of Applied Ecology(应用生态学报),2011,22(8):2193-2200(in Chinese)
[92]Forsum A,Laudon H,Nordin A.Nitrogen uptake by Hylocomium splendens during snowmelt in a boreal forest.Ecoscience,2008,15:315-319
[93]Bilbrough CJ,Caldwell MM.Exploitation of springtime ephemeral N pulses by six Great Basin plant species.Ecology,1997,78:231-243
[94]Campbell JL,Mitchell MJ,Groffman PM,et al.Winter in northeastern North America:A critical period for ecological processes.Frontiers in Ecology and the Environment,2005,3:314-322
[95]Monson RK,Lipson DL,Burns SP,et al.Winter forest soil respiration controlled by climate and microbial community composition.Nature,2006,439:711-714
[96]Lipson DA,Schmidt SK,Monson RK.Carbon availability and temperature control the post-snowmelt decline in alpine soil microbial biomass.Soil Biology and Biochemistry,2000,32:441-448
[97]Litaor MI,Mancinelli R,Halfpenny JC.The influence of pocket gophers on the status of nutrients in alpine soils.Geoderma,1996,70:37-48
[98]Huish S,Leonard MA,Anderson JM.Wetting and drying effects on animal-microbial mediated nitrogen mineralization and mineral element losses from deciduous forest litter and raw humus.Pedobiologia,1985,28:177-183
[99]O’lear HA,Seastedt TR.Landscape patterns of litter decomposition in alpine tundra.Oecologia,1994,99:95-101
[100]He R-L(和润莲),Chen Y-M(陈亚梅),Deng C-C(邓长春),et al.Litter decomposition and soil faunal diversity of two understory plant debris in the alpine timberline ecotone of western Sichuan in a snow cover season.Chinese Journal of Applied Ecology(应用生态学报),2015,26(3):723-731(in Chinese)
[101]Tan B(谭波),Wu F-Z(吴福忠),Yang W-Q(杨万勤),et al.Effects of snow pack removal on the dynamics of winter-time soil temperature,carbon,nitrogen,and phosphorus in alpine forests of west Sichuan.Chinese Journal of Applied Ecology(应用生态学报),2011,22(10):2553-2559(in Chinese)
[102]He W,Wu F,Zhang D,et al.The effects of forest gaps on cellulose degradation in the foliar litter of two shrub species in an alpine fir forest.Plant and Soil,2015,393:109-122
[2]Walther GR,Post E,Convey P,et al.Ecological responses to recent climate change.Nature,2002,416:389-395
[3]Lundquist JD,Neiman PJ,Martner B,et al.Rain versus snow in the Sierra Nevada,California:Comparing Doppler profiling radar and surface observations of melting level.Journal of Hydrometeorology,2008,9:194-211
[4]Vankoughnett MR,Henry HA.Soil freezing and N deposition:Transient vs.multi-year effects on plant productivity and relative species abundance.New Phytologist,2014,202:1277-1285
[5]Hayhoe K,Wake CP,Huntington TG,et al.Past and future changes in climate and hydrological indicators in the US Northeast.Climate Dynamics,2007,28:381-407
[6]Li P-J(李培基).Preliminary evaluation of seasonal snow resources in China.Acta Geographica Sinica(地理学报),1988,43(2):108-119(in Chinese)
[7]Venalainen A,Tuomenvirta H,Heikinheimo M,et al.Impact of climate change on soil frost under snow cover in a forested landscape.Climate Research,2001,17:63-72
[8]Uhlmann B,Goyette S,Beniston M.Sensitivity analysis of snow patterns in Swiss ski resorts to shifts in temperature,precipitation and humidity under conditions of climate change.International Journal of Climatology,2009,29:1048-1055
[9]Mote PW,Hamlet AF,Clark MP,et al.Declining mountain snowpack in western north America.Bulletin of the American Meteorological Society,2005,86:39-49
[10]Brooks PD,Grogan P,Templer PH,et al.Carbon and nitrogen cycling in snow-covered environments.Geography Compass,2011,5:682-699
[11]Qin DH,Liu SY,Li PJ.Snow cover distribution,variability,and response to climate change in western China.Journal of Climate,2006,19:1820-1833
[12]Beniston M,Keller F,Goyette S.Snow pack in the Swiss Alps under changing climatic conditions:An empirical approach for climate impacts studies.Theoretical and Applied Climatology,2003,74:19-31
[13]Wang G-X(王根绪),Li Q(李琪),Cheng G-D(程国栋),et al.Climate change and its impact on the eco-environment in the source regions of the Yangtze and Yellow Rivers in recent 40 years.Journal of Glaciology and Geocryology(冰川冻土),2001,23(4):346-352(in Chinese)
[14]Kreyling J,Haei M,Laudon H.Absence of snow cover reduces understory plant cover and alters plant community composition in boreal forests.Oecologia,2012,168:577-587
[15]Robroek BJ,Heijboer A,Jassey VE,et al.Snow cover manipulation effects on microbial community structure and soil chemistry in a mountain bog.Plant and Soil,2013,369:151-164
[16]Jusselme MD,Saccone P,Zinger L,et al.Variations in snow depth modify N-related soil microbial abundances and functioning during winter in subalpine grassland.Soil Biology and Biochemistry,2016,92:27-37
[17]Berg B.Litter decomposition and organic matter turnover in northern forest soils.Forest Ecology and Management,2000,133:13-22
[18]Schimel JP,Bennett J.Nitrogen mineralization:Challenges of a changing paradigm.Ecology,2004,85:591-602
[19]Jones HG.Snow Ecology:An Interdisciplinary Examination of Snow-Covered Ecosystems.Cambridge:Cambridge University Press,2001
[20]Bokhorst S,Metcalfe DB,Wardle DA.Reduction in snow depth negatively affects decomposers but impact on decomposition rates is substrate dependent.Soil Biology and Biochemistry,2013,62:157-164
[21]Buckeridge KM,Grogan P.Deepened snow alters soil microbial nutrient limitations in arctic birch hummock tundra.Applied Soil Ecology,2008,39:210-222
[22]Neff JC,Holland EA,Dentener FJ,et al.The origin,composition and rates of organic nitrogen deposition:Amissing piece of the nitrogen cycle?Biogeochemistry,2002,57:99-136
[23]Brooks PD,Williams MW.Snowpack controls on nitrogen cycling and export in seasonally snow-covered catchments.Hydrological Processes,1999,13:2177-2190
[24]Brown RD,Mote PW.The response of northern hemisphere snow cover to a changing climate.Journal of Climate,2009,22:2124-2145
[25]IPCC.Climate Change 2007:The Physical Science Basis.Cambridge:Cambridge University Press,2007
[26]Aerts R,Callaghan TV,Dorrepaal E,et al.Seasonal climate manipulations result in species-specific changes in leaf nutrient levels and isotopic composition in a subarctic bog.Functional Ecology,2009,23:680-688
[27]Uchida M,Mo W,Nakatsubo T,et al.Microbial activity and litter decomposition under snow cover in a cooltemperate broad-leaved deciduous forest.Agricultural and Forest Meteorology,2005,134:102-109
[28]Baptist F,Yoccoz NG,Choler P.Direct and indirect control by snow cover over decomposition in alpine tundra along a snowmelt gradient.Plant and Soil,2010,328:397-410
[29]Aerts R,Callaghan TV,Dorrepaal E,et al.Seasonal climate manipulations have only minor effects on litter decomposition rates and N dynamics but strong effects on litter P dynamics of sub-arctic bog species.Oecologia,2012,170:809-819
[30]Christenson LM,Mitchell MJ,Groffman PM,et al.Winter climate change implications for decomposition in northeastern forests:Comparisons of sugar maple litter with herbivore fecal inputs.Global Change Biology,2010,16:2589-2601
[31]Hu X(胡霞),Wu N(吴宁),Wu Y(吴彦),et al.Effects of snow cover on the decomposition and nutrient dynamics of Sibiraea angustata leaf litter in western Sichuan Plateau,Southwest China.Chinese Journal of Applied Ecology(应用生态学报),2012,23(5):1226-1232(in Chinese)
[32]Huang C,Wu F,Yang W,et al.Effects of snow thickness on the abundance of archaeal and bacterial amo Agenes and gene transcripts during dwarf bamboo litter decomposition in an alpine forest on the eastern Tibetan Plateau.Russian Journal of Ecology,2016,47:419-429
[33]Li H,Wu F,Yang W,et al.Effects of forest gaps on litter lignin and cellulose dynamics vary seasonally in an alpine forest.Forests,2016,7:27,doi:10.3390/f7020027
[34]Ni X,Yang W,Li H,et al.The responses of early foliar litter humification to reduced snow cover during winter in an alpine forest.Canadian Journal of Soil Science,2014,94:453-461
[35]Wu Q-G(吴庆贵),Wu F-Z(吴福忠),Tan B(谭波),et al.Effects of gap sizes on foliar litter decomposition in alpine forests.Acta Ecologica Sinica(生态学报),2016,36(12):3537-3545(in Chinese)
[36]Wu Q-Q(武启骞),Wu F-Z(吴福忠),Yang W-Q(杨万勤),et al.Effect of seasonal snow cover on litter decomposition in alpine forest.Chinese Journal of Plant Ecology(植物生态学报),2013,37(4):296-305(in Chinese)
[37]Shibata H,Hasegawa Y,Watanabe T,et al.Impact of snowpack decrease on net nitrogen mineralization and nitrification in forest soil of northern Japan.Biogeochemistry,2013,116:69-82
[38]Gavazov KS.Dynamics of alpine plant litter decomposition in a changing climate.Plant and Soil,2010,337:19-32
[39]Wipf S,Rixen C.A review of snow manipulation experiments in Arctic and alpine tundra ecosystems.Polar Research,2010,29:95-109
[40]Wu FZ,Yang WQ,Zhang J,et al.Litter decomposition in two subalpine forests during the freeze-thaw season.Acta Oecologica,2010,36:135-140
[41]Groffman PM,Driscoll CT,Fahey TJ,et al.Effects of mild winter freezing on soil nitrogen and carbon dynamics in a northern hardwood forest.Biogeochemistry,2001,56:191-213
[42]He J(何洁),Jiang X-M(蒋先敏),Yang W-Q(杨万勤),et al.Effects of snow patches on the release of N and P during foliar litter decomposition in an alpine forest of western Sichuan,China.Chinese Journal of Applied Ecology(应用生态学报),2014,25(8):2158-2166(in Chinese)
[43]Lemma B,Nilsson I,Kleja DB,et al.Decomposition and substrate quality of leaf litters and fine roots from three exotic plantations and a native forest in the southwestern highlands of Ethiopia.Soil Biology and Biochemistry,2007,39:2317-2328
[44]Bardgett R.The Biology of Soil:A Community and Ecosystem Approach.Oxford:Oxford University Press,2005
[45]Hagvar S,Hagvar EB.Invertebrate activity under snow in a South-Norwegian spruce forest.Soil Organisms,2011,83:187-209
[46]Holmstrup M,Hedlund K,Boriss H.Drought acclimation and lipid composition in Folsomia candida:Implications for cold shock,heat shock and acute desiccation stress.Journal of Insect Physiology,2002,48:961-970
[47]Pesaro M,Widmer F,Nicollier G,et al.Effects of freeze-thaw stress during soil storage on microbial communities and methidathion degradation.Soil Biology and Biochemistry,2003,35:1049-1061
[48]Schmidt SK,Lipson DA.Microbial growth under the snow:Implications for nutrient and allelochemical availability in temperate soils.Plant and Soil,2004,259:1-7
[49]Wu Q,Wu F,Yang W,et al.Foliar litter nitrogen dynamics as affected by forest gap in the alpine forest of eastern Tibet Plateau.PLo S One,2014,9(5):e97112
[50]Bell TH,Klironomos JN,Henry HA.Seasonal responses of extracellular enzyme activity and microbial biomass to warming and nitrogen addition.Soil Science Society of America Journal,2010,74:820-828
[51]Wu Y(吴彦).Effects of seasonal snow cover on plant community.Journal of Mountain Science(山地学报),2005,23(5):550-556(in Chinese)
[52]Wahren CHA,Walker MD,Bret-Harte MS.Vegetation responses in Alaskan arctic tundra after 8 years of a summer warming and winter snow manipulation experiment.Global Change Biology,2005,11:537-552
[53]Groffman PM,Driscoll CT,Fahey TJ,et al.Colder soils in a warmer world:A snow manipulation study in a northern hardwood forest ecosystem.Biogeochemistry,2001,56:135-150
[54]Tierney GL,Fahey TJ,Groffman PM,et al.Soil freezing alters fine root dynamics in a northern hardwood forest.Biogeochemistry,2001,56:175-190
[55]Waker MD,Ingersoll RC,Webber PJ.Effects of interannual climate variation on phenology and growth of two alpine forbs.Ecology,1995,76:1067-1083
[56]Davies TD,Tranter M,Jickells TD,et al.Heavilycontaminated snowfalls in the remote Scottish Highlands:A consequence of regional-scale mixing and transport.Atmospheric Environment Part A General Topics,1992,26:95-112
[57]Guan J-Q(关俊祺),Cai T-J(蔡体久),Man X-L(满秀玲).Characteristics of snowpack chemistry in different type plantations of Xiaoxing’an Mountains,northeastern China.Journal of Beijing Forestry University(北京林业大学学报),2013,35(4):41-46(in Chinese)
[58]Buckeridge KM,Cen YP,Layzell DB,et al.Soil biogeochemistry during the early spring in low arctic mesic tundra and the impacts of deepened snow and enhanced nitrogen availability.Biogeochemistry,2010,99:127-141
[59]Buckeridge KM,Grogan P.Deepened snow increases late thaw biogeochemical pulses in mesic low arctic tundra.Biogeochemistry,2010,101:105-121
[60]Fitzhugh RD,Driscoll CT,Groffman PM,et al.Effects of soil freezing disturbance on soil solution nitrogen,phosphorus,and carbon chemistry in a northern hardwood ecosystem.Biogeochemistry,2001,56:215-238
[61]Freppaz M,Celi L,Marchelli M,et al.Snow removal and its influence on temperature and N dynamics in alpine soils(Vallee d’Aoste,northwest Italy).Journal of Plant Nutrition and Soil Science,2008,171:672-680
[62]Groffman PM,Hardy JP,Nolan S,et al.Snow depth,soil frost and nutrient loss in a northern hardwood forest.Hydrological Processes,1999,13:2275-2286
[63]Groffman PM,Hardy JP,Driscoll CT,et al.Snow depth,soil freezing,and fluxes of carbon dioxide,nitrous oxide and methane in a northern hardwood forest.Global Change Biology,2006,12:1748-1760
[64]Groffman PM,Hardy JP,Fashu-Kanu S,et al.Snow depth,soil freezing and nitrogen cycling in a northern hardwood forest landscape.Biogeochemistry,2011,102:223-238
[65]Hentschel K,Borken W,Zuber T,et al.Effects of soil frost on nitrogen net mineralization,soil solution chemistry and seepage losses in a temperate forest soil.Global Change Biology,2009,15:825-836
[66]Pilon CE,C8téB,Fyles JW.Effect of snow removal on leaf water potential,soil moisture,leaf and soil nutrient status and leaf peroxidase activity of sugar maple.Plant and Soil,1994,162:81-88
[67]Steinweg JM,Fisk MC,Mc Alexander B,et al.Experimental snowpack reduction alters organic matter and net N mineralization potential of soil macroaggregates in a northern hardwood forest.Biology and Fertility of Soils,2008,45:1-10
[68]Sulkava P,Huhta V.Effects of hard frost and freezethaw cycles on decomposer communities and N mineralisation in boreal forest soil.Applied Soil Ecology,2003,22:225-239
[69]Tan B,Wu FZ,Yang WQ,et al.Snow removal alters soil microbial biomass and enzyme activity in a Tibetan alpine forest.Applied Soil Ecology,2014,76:34-41
[70]Viglietti D,Freppaz M,Filippa G,et al.Soil C and Nresponse to changes in winter precipitation in a subalpine forest ecosystem,NW Italy.Hydrological Processes,2014,28:5309-5321
[71]Jones HG.The ecology of snow-covered systems:A brief overview of nutrient cycling and life in the cold.Hydrological Processes,1999,13:2135-2147
[72]Williams MW,Bales RC,Brown AD,et al.Fluxes and transformations of nitrogen in a high-elevation catchment,Sierra Nevada.Biogeochemistry,1995,28:1-31
[73]Williams MW,Tonnessen KA.Critical loads for inorganic nitrogen deposition in the Colorado Front Range,USA.Ecological Applications,2000,10:1648-1665
[74]De Marco J,Mack MC,Bret-Harte MS.The effects of snow,soil microenvironment,and soil organic matter quality on N availability in three Alaskan arctic plant communities.Ecosystems,2011,14:804-817
[75]Schimel JP,Bilbrough C,Welker JM.Increased snow depth affects microbial activity and nitrogen mineralization in two Arctic tundra communities.Soil Biology and Biochemistry,2004,36:217-227
[76]Brooks PD,Schmidt SK,Williams MW.Winter production of CO2and N2O from alpine tundra:Environmental controls and relationship to inter-system C and N fluxes.Oecologia,1997,110:403-413
[77]Schürmann A,Mohn J,Bachofen R.N2O emissions from snow covered soils in the Swiss Alps.Tellus B,2002,54:134-142
[78]Teepe R,Brumme R,Beese F.Nitrous oxide from frozen soils under agriculture,fallow and forest.Soil Biology and Biochemistry,2000,32:1807-1810
[79]Maljanen M,Alm J,Martikainen PJ,et al.Prolongation of soil frost resulting from reduced snow cover increases nitrous oxide emissions from boreal forest soil.Boreal Environment Research,2010,15:34-42
[80]Koponen HT,Jaakkola T,Keinanen-Toivola MM,et al.Microbial communities,biomass,and activities in soils as affected by freeze thaw cycles.Soil Biology and Biochemistry,2006,38:1861-1871
[81]Wang H-Y(王怀玉),Yang W-Q(杨万勤).Effects of seasonal freeze-thaw cycles on quantity of soil microbes in the subalpine fir forest.Scientia Silvae Sinicae(林业科学),2012,48(5):88-94(in Chinese)
[82]Larsen KS,Jonasson S,Michelsen A.Repeated freezethaw cycles and their effects on biological processes in two arctic ecosystem types.Applied Soil Ecology,2002,21:187-195
[83]Sjursen H,Michelsen A,Holmstrup M.Effects of freeze-thaw cycles on microarthropods and nutrient availability in a sub-Arctic soil.Applied Soil Ecology,2005,28:79-93
[84]Wang L-Q(王丽芹),Qi Y-C(齐玉春),Dong Y-S(董云社),et al.Effects and mechanism of freezethawing cycles on key processes of nitrogen cycle in terrestrial ecosystem.Chinese Journal of Applied Ecology(应用生态学报),2015,26(11):3532-3544(in Chinese)
[85]Freppaz M,Williams BL,Edwards AC,et al.Simulating soil freeze/thaw cycles typical of winter alpine conditions:Implications for N and P availability.Applied Soil Ecology,2007,35:247-255
[86]Li S-N(李胜男),Fan Z-P(范志平),Li F-Y(李法云),et al.Responses of soil nitrogen transformation process to freezing-thawing cycle in a riparian zone under three different vegetation types.Chinese Journal of Ecology(生态学杂志),2013,32(6):1391-1398(in Chinese)
[87]Deluca TH,Keeney DR,Mccarty GW.Effect of freezethaw events on mineralization of soil nitrogen.Biology and Fertility of Soils,1992,14:116-120
[88]Tao N(陶娜),Zhang X-Y(张馨月),Zeng H(曾辉),et al.Seasonal characteristics of soil CO2efflux and carbon and nitrogen cycling induced by microorganisms in snow-covered and frozen soil system.Microbiology China(微生物学通报),2013,40(1):146-157(in Chinese)
[89]Yanai Y,Toyota K,Okazaki M.Response of denitrifying communities to successive soil freeze-thaw cycles.Biology and Fertility of Soils,2007,44:113-119
[90]Teepe R,Brumme R,Beese F.Nitrous oxide emissions from soil during freezing and thawing periods.Soil Biology and Biochemistry,2001,33:1269-1275
[91]Liu L(刘琳),Wu Y(吴彦),He Y-X(何奕忻),et al.Effects of seasonal snow cover on soil nitrogen transformation in alpine ecosystem:A review.Chinese Journal of Applied Ecology(应用生态学报),2011,22(8):2193-2200(in Chinese)
[92]Forsum A,Laudon H,Nordin A.Nitrogen uptake by Hylocomium splendens during snowmelt in a boreal forest.Ecoscience,2008,15:315-319
[93]Bilbrough CJ,Caldwell MM.Exploitation of springtime ephemeral N pulses by six Great Basin plant species.Ecology,1997,78:231-243
[94]Campbell JL,Mitchell MJ,Groffman PM,et al.Winter in northeastern North America:A critical period for ecological processes.Frontiers in Ecology and the Environment,2005,3:314-322
[95]Monson RK,Lipson DL,Burns SP,et al.Winter forest soil respiration controlled by climate and microbial community composition.Nature,2006,439:711-714
[96]Lipson DA,Schmidt SK,Monson RK.Carbon availability and temperature control the post-snowmelt decline in alpine soil microbial biomass.Soil Biology and Biochemistry,2000,32:441-448
[97]Litaor MI,Mancinelli R,Halfpenny JC.The influence of pocket gophers on the status of nutrients in alpine soils.Geoderma,1996,70:37-48
[98]Huish S,Leonard MA,Anderson JM.Wetting and drying effects on animal-microbial mediated nitrogen mineralization and mineral element losses from deciduous forest litter and raw humus.Pedobiologia,1985,28:177-183
[99]O’lear HA,Seastedt TR.Landscape patterns of litter decomposition in alpine tundra.Oecologia,1994,99:95-101
[100]He R-L(和润莲),Chen Y-M(陈亚梅),Deng C-C(邓长春),et al.Litter decomposition and soil faunal diversity of two understory plant debris in the alpine timberline ecotone of western Sichuan in a snow cover season.Chinese Journal of Applied Ecology(应用生态学报),2015,26(3):723-731(in Chinese)
[101]Tan B(谭波),Wu F-Z(吴福忠),Yang W-Q(杨万勤),et al.Effects of snow pack removal on the dynamics of winter-time soil temperature,carbon,nitrogen,and phosphorus in alpine forests of west Sichuan.Chinese Journal of Applied Ecology(应用生态学报),2011,22(10):2553-2559(in Chinese)
[102]He W,Wu F,Zhang D,et al.The effects of forest gaps on cellulose degradation in the foliar litter of two shrub species in an alpine fir forest.Plant and Soil,2015,393:109-122