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本研究在中国云杉林的全部自然分布范围内(23°-53°N,75°-134°E,海拔250-4300 m),采样调查了172个样方,收集其群落的物种组成、地理坐标、地形信息和样地的气候数据.这16个自然分布的云杉类群,被分为不同形态学组和系统发育进化枝.采用多元分析方法,包括双向指标物种分析、主成分分析、除趋势对应分析、典型对应分析(CCA)和部分典型对应分析,对中国云杉林地理分布、云杉属形态分化和系统发育分异与环境因子间的关系进行研究,以揭示中国云杉林的地理分布规律,阐明各群系建群种的形态分化和系统发育分异的驱动机制.结果表明,172个样方可归为13个云杉林群系,各群系的地理分布与经纬度和气候因子密切相关:经纬度对中国云杉林物种组成变化的解释量为32.01％,显著高于气候因子(27.76％)和地形因子(23.32％).在三个形态学组里面,鱼鳞云杉组(sect.Omorica)的物种主要分布在较湿润的区域,年均降水量比丽江云杉组(sect.Casicta)多229 mm,比云杉组(sect.Picea)多426 mm.在中国云杉属的两个系统发育进化枝中,较古老的分枝(Clade-Ⅱ)主要分布于温度年较差较小的区域,其最冷月均温比较年轻的分枝(Clade-Ⅲ)高8-10℃,但前者生长季≥5℃有效积温比后者低约297-438℃.本研究结果支持地理位置可能是物种组成分异的主要决定因素这一假设.此外,湿度是云杉属各形态组间分异的决定因子,而云杉属系统发育分异则主要受温度的影响.可见,尽管云杉属的形态分化和系统发育分异均受气候的影响,但两者的选择压力并不相同.“,”Aims We aimed to elucidate the driving forces underlying the geographical distribution of spruce forests,as well as the morphological and phylogenetic divergence among spruce species in China.Methods One hundred and seventy two sites across the entire range of spruce forests in China(23°-53° N,75°-134° E,250-4300 m a.s.l.)were sampled for species composition,geographical coordinates,and topographic and climatic variables.Sixteen spruce taxa,which are naturally distributed in China,were respectively grouped into morphologically defined sections and phylogenetically distinct clades.Multivariate approaches,including two-way indicator species analysis,principal components analysis,detrended correspondence analysis,canonical correspondence analysis(CCA),and partial CCA,were used for data analysis.Important Findings The 172 samples grouped into 13 spruce forests,the geographical distributions of which were closely related to climate and geographical location.The variation in species composition explained by the geographical coordinates(32.01％)was significantly higher than that explained by the climatic(27.76％)and topographic variables(23.32％).Of the three morphologically defined sections,sect.Omorica occurred mainly in wetter habitats with a mean annual precipitation of ca.229 mm and 426 mm higher than the habitats of sect.Casicta and sect.Picea(P＜0.01),respectively.Of the two phylogenetically distinct clades,Clade-Ⅱ(an older clade)occurred in habitats with warm winters and cool summers whose mean temperature in the coldest month was ca.8-10℃higher,yet accumulated temperature during the growing season(≥5℃)was ca.297-438℃lower,than the habitats of Clade-Ⅲ(a younger clade)(P＜0.01).Our data support the hypothesis that geographical location may be a greater determinant of variation in species composition.In addition,moisture conditions tend to be the key determinants that account for the divergence among the morphologically defined sections,while the phylogenetic divergence among spruce species is mainly affected by temperature conditions.While the clades or sections of the spruce species in question carry strong climatic signals,their divergences are subject to different selective pressures.