基于孢粉的古气候参数定量重建:一种新思路及其在中国的应用实例
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摘要
传统的孢粉-古气候定量重建评估主要衡量校准集对现代气候状况的模拟结果或化石样品与校准集样品的可比程度,客观上导致特定地点重建气候参数的取舍缺少明确标准.基于国际上通过随机数据开展定量重建显著性检验的新方法,充分利用中国环境梯度大、植被类型丰富、现代表土孢粉数据完善等优势,提出一种孢粉-古气候参数定量重建的新思路:首先确定控制化石孢粉组成变化最主要环境因子,随后通过限制其他环境因子来构造校准集以开展该因子的定量重建,最后完成重建结果显著性评估.将该思路应用于分别位于黄土高原东、西两侧的吕梁山公海和六盘山天池化石孢粉序列,所获得的年降水量P_(ann)定量重建不仅具有统计上的显著性(p<0.001),且相互间在共同时段表现出良好、稳定的相关关系,均指示了约3300cal a BP以来的东亚夏季风降水快速下降,显示其具备降低基于孢粉的古气候参数定量重建不确定性的较大潜力.
引文
陈建徽,饶志国,刘建宝,黄伟,Feng S,董广辉,胡玉,许清海,陈发虎.2016.全新世东亚夏季风最强盛期出现在何时?——兼论中国南方石笋氧同位素的古气候意义.中国科学:地球科学,46:1494-1504
方修琦,侯光良.2011.中国全新世气温序列的集成重建.地理科学,31:385-393
秦锋,赵艳.2013.基于孢粉组合定量重建古气候的方法在中国的运用及思考.第四纪研究,33:1054-1068
宋长青,孙湘君.1997.花粉-气候因子转换函数建立及其对古气候因子定量重建.植物学报,39:554-560
童国榜,吴瑞金.1997.龙感湖地区近3000年来的植被及其气候定量重建.海洋地质与第四纪地质,17:53-61
肖景义,陈建强,李辉,许哲平,孙刚,牛彩香,杨国臣.2008.河北邯郸HZ-S孔第四纪孢粉组合的定量分析.地质通报,27:599-604
许清海,李曼玥,张生瑞,张娅红,张攀攀,卢静瑶.2015.中国第四纪花粉现代过程:进展与问题.中国科学:地球科学,45:1661-1682
郑卓,Guiot J.1999.我国热带地区40万年以来古气候的定量恢复.中山大学学报:自然科学版,38:94-98
郑卓,张潇,满美玲,魏金辉,黄康有.2016.中国及邻区利用孢粉进行定量古气候重建的回顾与数据集成.第四纪研究,36:503-519
中国植被编辑委员会.1980.中国植被.北京:科学出版社.1382
周爱锋,孙惠玲,陈发虎,赵艳,安成邦,董广辉,王宗礼,陈建徽.2010.黄土高原六盘山天池记录的中晚全新世高分辨率气候变化及其意义.科学通报,55:2263-2266
朱诚,陈星,马春梅,朱青,李中轩,徐伟峰.2008.神农架大九湖孢粉气候因子转换函数与古气候重建.科学通报,53:38-44
Amesbury M J,Swindles G T,Bobrov A,Charman D J,Holden J,Lamentowicz M,Mallon G,Mazei Y,Mitchell E A D,Payne R J,Roland T P,Turner T E,Warner B G.2016.Development of a new pan-European testate amoeba transfer function for reconstructingpeatland palaeohydrology.Quat Sci Rev,152:132-151
Bennett K D,Willis K J.2001.Pollen.In:Smol J P,Birks H J B,Last W M,eds.Tracking Environmental Change Using Lake Sediments-Terrestrial,Algal,and Siliceous Indicators.Dordrecht:Springer Netherlands.5-32
Birks H J B.1998.Numerical tools in palaeolimnology-Progress,potentialities,and problems.J Paleolimn,20:301-332
Birks H J B,Gordon A D.1985.Numerical Methods in Quaternary Pollen Analysis.London:Academic Press.317
Birks H J B,Lotter A F,Juggins S,Smol J P.2012.Tracking Environmental Change Using Lake Sediments-Data Handling and Numerical Techniques.Heidelberg:Springer.745
Cao X Y,Herzschuh U,Telford R J,Ni J.2014.A modern pollen-climate dataset from China and Mongolia:Assessing its potential for climate reconstruction.Rev Palaeobot Palynol,211:87-96
Chen F,Chen X,Chen J,Zhou A,Wu D,Tang L,Zhang X,Huang X,Yu J.2014.Holocene vegetation history,precipitation changes and Indian Summer Monsoon evolution documented from sediments of Xingyun Lake,south-west China.J Quat Sci,29:661-674
Chen F,Xu Q,Chen J,Birks H J B,Liu J,Zhang S,Jin L,An C,Telford R J,Cao X,Wang Z,Zhang X,Selvaraj K,Lu H,Li Y,Zheng Z,Wang H,Zhou A,Dong G,Zhang J,Huang X,Bloemendal J,Rao Z.2015.East Asian summer monsoon precipitation variability since the last deglaciation.Sci Rep,5:11186
Cooper G R J,Cowan D R.2008.Comparing time series using waveletbased semblance analysis.Comp Geosciences,34:95-102
Ge Q,Wang S,Wen X,Shen C,Hao Z.2007.Temperature and precipitation changes in China during the Holocene.Adv Atmos Sci,24:1024-1036
Guiot J,Torre F,Jolly D,Peyron O,Boreux J J,Cheddadi R.2000.Inverse vegetation modeling by Monte Carlo sampling to reconstruct palaeoclimates under changed precipitation seasonality and CO_2 conditions:Application to glacial climate in Mediterranean region.Ecol Model,127:119-140
Herzschuh U,Birks H J B,Mischke S,Zhang C,Bohner J.2010.A modern pollen-climate calibration set based on lake sediments from the Tibetan Plateau and its application to a Late Quaternary pollen record from the Qilian Mountains.J Biogeogr,37:752-766
Herzschuh U,Borkowski J,Schewe J,Mischke S,Tian F.2014.Moisture-advection feedback supports strong early-to-mid Holocene monsoon climate on the eastern Tibetan Plateau as inferred from a pollenbased reconstruction.Palaeogeogr Palaeoclimatol Palaeoecol,402:44-54
Jiang D,Lang X,Tian Z,Wang T.2012.Considerable model-data mismatch in temperature over China during the Mid-Holocene:Results of PMIP simulations.J Clim,25:4135-4153
Jiang W,Guiot J L,Chu G,Wu H,Yuan B,HattéC,Guo Z.2010.An improved methodology of the modern analogues technique for palaeoclimate reconstruction in arid and semi-arid regions.Boreas,39:145-153
Jones R T,Turney C S M,Lang B,Brooks S J,Rundgren M,Hammarlund D,Bjorck S,Fogwill C J.2017.Delayed maximum northern European summer temperatures during the Last Interglacial as a result of Greenland Ice Sheet melt.Geology,45:23-26
Juggins S.2015.Rioja:Analysis of Quaternary Science Data,R package version 0.9-9.Newcastle upon Tyne:University of Newcastle
Juggins S,Birks H J B.2012.Quantitative environmental reconstructions from biological Data.In:Birks H J B,Lotter A F,Juggins S,Smol J P,eds.Tracking Environmental Change Using Lake Sediments:Data Handling and Numerical Techniques.Dordrecht:Springer Netherlands.431-494
Li J,Dodson J,Yan H,Zhang D D,Zhang X,Xu Q,Lee H F,Pei Q,Cheng B,Li C,Ni J,Sun A,Lu F,Zong Y.2017.Quantifying climatic variability in monsoonal northern China over the last 2200 years and its role in driving Chinese dynastic changes.Quat Sci Rev,159:35-46
Li Q,Wu H,Yu Y,Sun A,Markovic S B,Guo Z.2014.Reconstructed moisture evolution of the deserts in northern China since the Last Glacial Maximum and its implications for the East Asian Summer Monsoon.Glob Planet Change,121:101-112
Lu H,Wu N,Liu K,Zhu L,Yang X,Yao T,Wang L,Li Q,Liu X,Shen C,Li X,Tong G,Jiang H.2011.Modern pollen distributions in Qinghai-Tibetan Plateau and the development of transfer functions for reconstructing Holocene environmental changes.Quat Sci Rev,30:947-966
Luoto T P,Nevalainen L.2013.Long-term water temperature reconstructions from mountain lakes with different catchment and morphometric features.Sci Rep,3:2488
Ni J,Cao X,Jeltsch F,Herzschuh U.2014.Biome distribution over the last 22000 yr in China.Palaeogeogr Palaeoclimatol Palaeoecol,409:33-47
Oksanen J,Blanchet F G,Friendly M,Kindt R,Legendre P,McGlinn D,Minchin P R,O'Hara R B,Simpson G L,Solymos P,Henry M,Stevens H,Szoecs E,Wagner H.2017.Vegan:Community Ecology Package,R package version 2.4-2.Oulu:University of Oulu
R Core Team 2013.R:A language and environment for statistical computing.Vienna:R Foundation for Statistical Computing
Rehfeld K,Trachsel M,Telford R J,Laepple T.2016.Assessing performance and seasonal bias of pollen-based climate reconstructions in a perfect model world.Clim Past,12:2255-2270
Salonen J S,Luoto M,Alenius T,Heikkila M,Seppa H,Telford R J,Birks H J B.2014.Reconstructing palaeoclimatic variables from fossil pollen using boosted regression trees:Comparison and synthesiswith other quantitative reconstruction methods.Quat Sci Rev,88:69-81
Simpson G L.2012.Analogue Methods in Palaeolimnology.In:Birks H J B,Lotter A F,Juggins S,Smol J P,eds.Tracking Environmental Change Using Lake Sediments:Data Handling and Numerical Techniques.Dordrecht:Springer Netherlands.495-522
Stebich M,Rehfeld K,Schlutz F,Tarasov P E,Liu J,Mingram J.2015.Holocene vegetation and climate dynamics of NE China based on the pollen record from Sihailongwan Maar Lake.Quat Sci Rev,124:275-289
Telford R J,Birks H J B.2011.A novel method for assessing the statistical significance of quantitative reconstructions inferred from biotic assemblages.Quat Sci Rev,30:1272-1278
Telford R,Trachsel M.2015.PalaeoSig:Significance Tests for Palaeoenvironmental Reconstructions,R package version 1.1-3.Bergen:University of Bergen
Trauth M H.2015.MATLAB Recipes for Earth Sciences.4th ed.Verlag Berlin Heidelberg:Springer.427
Wang H,Chen J,Zhang X,Chen F.2014.Palaeosol development in the Chinese Loess Plateau as an indicator of the strength of the East Asian summer monsoon:Evidence for a mid-Holocene maximum.Quat Int,334-335:155-164
Wang S,Gong D,Zhu J.2001.Twentieth-century climatic warming in China in the context of the Holocene.Holocene,11:313-321
Wu H,Guiot J,Brewer S,Guo Z,Peng C.2007.Dominant factors controlling glacial and interglacial variations in the treeline elevation in tropical Africa.Proc Natl Acad Sci USA,104:9720-9724
Xu Q,Chen F,Zhang S,Cao X,Li J,Li Y,Li M,Chen J,Liu J,Wang Z.2017.Vegetation succession and East Asian Summer Monsoon Changes since the last deglaciation inferred from high-resolution pollen record in Gonghai Lake,Shanxi Province,China.Holocene,27:835-846
Xu Q,Xiao J,Li Y,Tian F,Nakagawa T.2010.Pollen-based quantitative reconstruction of holocene climate changes in the Daihai Lake Area,Inner Mongolia,China.J Clim,23:2856-2868
Yang S,Ding Z,Li Y,Wang X,Jiang W,Huang X.2015.Warminginduced northwestward migration of the East Asian monsoon rain belt from the Last Glacial Maximum to the mid-Holocene.Proc Natl Acad Sci USA,112:13178-13183
Zhang H,Zhang Y,Kong Z,Yang Z,Li Y,Tarasov P E.2015.Late Holocene climate change and anthropogenic activities in north Xinjiang:Evidence from a peatland archive,the Caotanhu wetland.Holocene,25:323-332
Zhao Y,Chen F,Zhou A,Yu Z,Zhang K.2010.Vegetation history,climate change and human activities over the last 6200 years on the Liupan Mountains in the southwestern Loess Plateau in central China.Palaeogeogr Palaeoclimatol Palaeoecol,293:197-205
Zhao H,Huang W,Feng S,Chen F,Xian W.2017.Optimization and evaluation of monthly air temperature and precipitation gridded datasets with 0.025°spatial resolution over China for 1951-2015.Theor Appl Climatol,under review
Zheng Z,Wei J,Huang K,Xu Q,Lu H,Tarasov P,Luo C,Beaudouin C,Deng Y,Pan A,Zheng Y,Luo Y,Nakagawa T,Li C,Yang S,Peng H,Cheddadi R.2014.East Asian pollen database:Modern pollen distribution and its quantitative relationship with vegetation and climate.J Biogeogr,41:1819-1832
1)根据现有资料,中国北方全新世年均温度变幅不超过5℃(Wang等,2001;Ge等,2007;方修琦和侯光良,2011),而全新世大暖期与现代年均温差为2~3℃(Jiang等,2012).事实上,此处取±2℃或±3℃所获重建结果变化基本一致(图略)
方修琦,侯光良.2011.中国全新世气温序列的集成重建.地理科学,31:385-393
秦锋,赵艳.2013.基于孢粉组合定量重建古气候的方法在中国的运用及思考.第四纪研究,33:1054-1068
宋长青,孙湘君.1997.花粉-气候因子转换函数建立及其对古气候因子定量重建.植物学报,39:554-560
童国榜,吴瑞金.1997.龙感湖地区近3000年来的植被及其气候定量重建.海洋地质与第四纪地质,17:53-61
肖景义,陈建强,李辉,许哲平,孙刚,牛彩香,杨国臣.2008.河北邯郸HZ-S孔第四纪孢粉组合的定量分析.地质通报,27:599-604
许清海,李曼玥,张生瑞,张娅红,张攀攀,卢静瑶.2015.中国第四纪花粉现代过程:进展与问题.中国科学:地球科学,45:1661-1682
郑卓,Guiot J.1999.我国热带地区40万年以来古气候的定量恢复.中山大学学报:自然科学版,38:94-98
郑卓,张潇,满美玲,魏金辉,黄康有.2016.中国及邻区利用孢粉进行定量古气候重建的回顾与数据集成.第四纪研究,36:503-519
中国植被编辑委员会.1980.中国植被.北京:科学出版社.1382
周爱锋,孙惠玲,陈发虎,赵艳,安成邦,董广辉,王宗礼,陈建徽.2010.黄土高原六盘山天池记录的中晚全新世高分辨率气候变化及其意义.科学通报,55:2263-2266
朱诚,陈星,马春梅,朱青,李中轩,徐伟峰.2008.神农架大九湖孢粉气候因子转换函数与古气候重建.科学通报,53:38-44
Amesbury M J,Swindles G T,Bobrov A,Charman D J,Holden J,Lamentowicz M,Mallon G,Mazei Y,Mitchell E A D,Payne R J,Roland T P,Turner T E,Warner B G.2016.Development of a new pan-European testate amoeba transfer function for reconstructingpeatland palaeohydrology.Quat Sci Rev,152:132-151
Bennett K D,Willis K J.2001.Pollen.In:Smol J P,Birks H J B,Last W M,eds.Tracking Environmental Change Using Lake Sediments-Terrestrial,Algal,and Siliceous Indicators.Dordrecht:Springer Netherlands.5-32
Birks H J B.1998.Numerical tools in palaeolimnology-Progress,potentialities,and problems.J Paleolimn,20:301-332
Birks H J B,Gordon A D.1985.Numerical Methods in Quaternary Pollen Analysis.London:Academic Press.317
Birks H J B,Lotter A F,Juggins S,Smol J P.2012.Tracking Environmental Change Using Lake Sediments-Data Handling and Numerical Techniques.Heidelberg:Springer.745
Cao X Y,Herzschuh U,Telford R J,Ni J.2014.A modern pollen-climate dataset from China and Mongolia:Assessing its potential for climate reconstruction.Rev Palaeobot Palynol,211:87-96
Chen F,Chen X,Chen J,Zhou A,Wu D,Tang L,Zhang X,Huang X,Yu J.2014.Holocene vegetation history,precipitation changes and Indian Summer Monsoon evolution documented from sediments of Xingyun Lake,south-west China.J Quat Sci,29:661-674
Chen F,Xu Q,Chen J,Birks H J B,Liu J,Zhang S,Jin L,An C,Telford R J,Cao X,Wang Z,Zhang X,Selvaraj K,Lu H,Li Y,Zheng Z,Wang H,Zhou A,Dong G,Zhang J,Huang X,Bloemendal J,Rao Z.2015.East Asian summer monsoon precipitation variability since the last deglaciation.Sci Rep,5:11186
Cooper G R J,Cowan D R.2008.Comparing time series using waveletbased semblance analysis.Comp Geosciences,34:95-102
Ge Q,Wang S,Wen X,Shen C,Hao Z.2007.Temperature and precipitation changes in China during the Holocene.Adv Atmos Sci,24:1024-1036
Guiot J,Torre F,Jolly D,Peyron O,Boreux J J,Cheddadi R.2000.Inverse vegetation modeling by Monte Carlo sampling to reconstruct palaeoclimates under changed precipitation seasonality and CO_2 conditions:Application to glacial climate in Mediterranean region.Ecol Model,127:119-140
Herzschuh U,Birks H J B,Mischke S,Zhang C,Bohner J.2010.A modern pollen-climate calibration set based on lake sediments from the Tibetan Plateau and its application to a Late Quaternary pollen record from the Qilian Mountains.J Biogeogr,37:752-766
Herzschuh U,Borkowski J,Schewe J,Mischke S,Tian F.2014.Moisture-advection feedback supports strong early-to-mid Holocene monsoon climate on the eastern Tibetan Plateau as inferred from a pollenbased reconstruction.Palaeogeogr Palaeoclimatol Palaeoecol,402:44-54
Jiang D,Lang X,Tian Z,Wang T.2012.Considerable model-data mismatch in temperature over China during the Mid-Holocene:Results of PMIP simulations.J Clim,25:4135-4153
Jiang W,Guiot J L,Chu G,Wu H,Yuan B,HattéC,Guo Z.2010.An improved methodology of the modern analogues technique for palaeoclimate reconstruction in arid and semi-arid regions.Boreas,39:145-153
Jones R T,Turney C S M,Lang B,Brooks S J,Rundgren M,Hammarlund D,Bjorck S,Fogwill C J.2017.Delayed maximum northern European summer temperatures during the Last Interglacial as a result of Greenland Ice Sheet melt.Geology,45:23-26
Juggins S.2015.Rioja:Analysis of Quaternary Science Data,R package version 0.9-9.Newcastle upon Tyne:University of Newcastle
Juggins S,Birks H J B.2012.Quantitative environmental reconstructions from biological Data.In:Birks H J B,Lotter A F,Juggins S,Smol J P,eds.Tracking Environmental Change Using Lake Sediments:Data Handling and Numerical Techniques.Dordrecht:Springer Netherlands.431-494
Li J,Dodson J,Yan H,Zhang D D,Zhang X,Xu Q,Lee H F,Pei Q,Cheng B,Li C,Ni J,Sun A,Lu F,Zong Y.2017.Quantifying climatic variability in monsoonal northern China over the last 2200 years and its role in driving Chinese dynastic changes.Quat Sci Rev,159:35-46
Li Q,Wu H,Yu Y,Sun A,Markovic S B,Guo Z.2014.Reconstructed moisture evolution of the deserts in northern China since the Last Glacial Maximum and its implications for the East Asian Summer Monsoon.Glob Planet Change,121:101-112
Lu H,Wu N,Liu K,Zhu L,Yang X,Yao T,Wang L,Li Q,Liu X,Shen C,Li X,Tong G,Jiang H.2011.Modern pollen distributions in Qinghai-Tibetan Plateau and the development of transfer functions for reconstructing Holocene environmental changes.Quat Sci Rev,30:947-966
Luoto T P,Nevalainen L.2013.Long-term water temperature reconstructions from mountain lakes with different catchment and morphometric features.Sci Rep,3:2488
Ni J,Cao X,Jeltsch F,Herzschuh U.2014.Biome distribution over the last 22000 yr in China.Palaeogeogr Palaeoclimatol Palaeoecol,409:33-47
Oksanen J,Blanchet F G,Friendly M,Kindt R,Legendre P,McGlinn D,Minchin P R,O'Hara R B,Simpson G L,Solymos P,Henry M,Stevens H,Szoecs E,Wagner H.2017.Vegan:Community Ecology Package,R package version 2.4-2.Oulu:University of Oulu
R Core Team 2013.R:A language and environment for statistical computing.Vienna:R Foundation for Statistical Computing
Rehfeld K,Trachsel M,Telford R J,Laepple T.2016.Assessing performance and seasonal bias of pollen-based climate reconstructions in a perfect model world.Clim Past,12:2255-2270
Salonen J S,Luoto M,Alenius T,Heikkila M,Seppa H,Telford R J,Birks H J B.2014.Reconstructing palaeoclimatic variables from fossil pollen using boosted regression trees:Comparison and synthesiswith other quantitative reconstruction methods.Quat Sci Rev,88:69-81
Simpson G L.2012.Analogue Methods in Palaeolimnology.In:Birks H J B,Lotter A F,Juggins S,Smol J P,eds.Tracking Environmental Change Using Lake Sediments:Data Handling and Numerical Techniques.Dordrecht:Springer Netherlands.495-522
Stebich M,Rehfeld K,Schlutz F,Tarasov P E,Liu J,Mingram J.2015.Holocene vegetation and climate dynamics of NE China based on the pollen record from Sihailongwan Maar Lake.Quat Sci Rev,124:275-289
Telford R J,Birks H J B.2011.A novel method for assessing the statistical significance of quantitative reconstructions inferred from biotic assemblages.Quat Sci Rev,30:1272-1278
Telford R,Trachsel M.2015.PalaeoSig:Significance Tests for Palaeoenvironmental Reconstructions,R package version 1.1-3.Bergen:University of Bergen
Trauth M H.2015.MATLAB Recipes for Earth Sciences.4th ed.Verlag Berlin Heidelberg:Springer.427
Wang H,Chen J,Zhang X,Chen F.2014.Palaeosol development in the Chinese Loess Plateau as an indicator of the strength of the East Asian summer monsoon:Evidence for a mid-Holocene maximum.Quat Int,334-335:155-164
Wang S,Gong D,Zhu J.2001.Twentieth-century climatic warming in China in the context of the Holocene.Holocene,11:313-321
Wu H,Guiot J,Brewer S,Guo Z,Peng C.2007.Dominant factors controlling glacial and interglacial variations in the treeline elevation in tropical Africa.Proc Natl Acad Sci USA,104:9720-9724
Xu Q,Chen F,Zhang S,Cao X,Li J,Li Y,Li M,Chen J,Liu J,Wang Z.2017.Vegetation succession and East Asian Summer Monsoon Changes since the last deglaciation inferred from high-resolution pollen record in Gonghai Lake,Shanxi Province,China.Holocene,27:835-846
Xu Q,Xiao J,Li Y,Tian F,Nakagawa T.2010.Pollen-based quantitative reconstruction of holocene climate changes in the Daihai Lake Area,Inner Mongolia,China.J Clim,23:2856-2868
Yang S,Ding Z,Li Y,Wang X,Jiang W,Huang X.2015.Warminginduced northwestward migration of the East Asian monsoon rain belt from the Last Glacial Maximum to the mid-Holocene.Proc Natl Acad Sci USA,112:13178-13183
Zhang H,Zhang Y,Kong Z,Yang Z,Li Y,Tarasov P E.2015.Late Holocene climate change and anthropogenic activities in north Xinjiang:Evidence from a peatland archive,the Caotanhu wetland.Holocene,25:323-332
Zhao Y,Chen F,Zhou A,Yu Z,Zhang K.2010.Vegetation history,climate change and human activities over the last 6200 years on the Liupan Mountains in the southwestern Loess Plateau in central China.Palaeogeogr Palaeoclimatol Palaeoecol,293:197-205
Zhao H,Huang W,Feng S,Chen F,Xian W.2017.Optimization and evaluation of monthly air temperature and precipitation gridded datasets with 0.025°spatial resolution over China for 1951-2015.Theor Appl Climatol,under review
Zheng Z,Wei J,Huang K,Xu Q,Lu H,Tarasov P,Luo C,Beaudouin C,Deng Y,Pan A,Zheng Y,Luo Y,Nakagawa T,Li C,Yang S,Peng H,Cheddadi R.2014.East Asian pollen database:Modern pollen distribution and its quantitative relationship with vegetation and climate.J Biogeogr,41:1819-1832
1)根据现有资料,中国北方全新世年均温度变幅不超过5℃(Wang等,2001;Ge等,2007;方修琦和侯光良,2011),而全新世大暖期与现代年均温差为2~3℃(Jiang等,2012).事实上,此处取±2℃或±3℃所获重建结果变化基本一致(图略)