Data from: Morphometric traits capture the climatically driven species turnover of 10 spruce taxa across China

This study explored the relative roles of climate and phylogenetic background in driving morphometric trait variation in 10 spruce taxa in China. The study further addressed the hypothesis that these variations are consistent with species turnover on climatic gradients. Nine morphometric traits of leaves, seed cones, and seeds for the 10 studied spruce taxa were measured at 504 sites. These data were analyzed in combination with species DNA sequences from NCBI GenBank. We detected the effects of phylogeny and climate through trait-variation-based K statistics and phylogenetic eigenvector regression (PVR) analyses. Multivariate analyses were performed to detect trait variation along climatic gradients with species replacement. The estimated K-values for the nine studied morphometric traits ranged from 0.19 to 0.68, and the studied environmental variables explained 39–83% of the total trait variation. Trait variation tended to be determined largely by a temperature gradient varying from wet-cool climates to dry-warm summers and, additionally, by a moisture gradient. As the climate became wetter and cooler, spruce species tended to be replaced by other spruces with smaller needle leaves and seeds but larger cones and seed scales. A regression analysis showed that spruce species tended to be successively replaced by other species, along the gradient, although the trends observed within species were not necessarily consistent with the overall trend. The climatically driven replacement of the spruces in question could be well indicated by the between-species variation in morphometric traits that carry lower phylogenetic signal. Between-species variation in these traits is driven primarily by climatic factors. These species demonstrate a narrower ecological amplitude in temperature but wider ranges on the moisture gradient.本研究探讨了气候与系统发育背景在驱动中国10个云杉类群形态性状变异中的相对作用。本研究进一步验证了如下假说：此类性状变异与气候梯度上的物种周转现象相一致。研究团队在504个样点对这10个云杉类群的叶片、种球及种子共9项形态性状进行了测量，并结合取自NCBI GenBank（美国国家生物技术信息中心基因数据库）的物种DNA序列对上述数据开展了联合分析。本研究通过基于性状变异的K统计量与系统发育特征向量回归（phylogenetic eigenvector regression, PVR）分析，检测了系统发育与气候的效应；同时通过多变量分析，探究了气候梯度上伴随物种更替的性状变异规律。本次研究涉及的9项形态性状的K统计量估计值介于0.19至0.68之间，所纳入的环境变量可解释总性状变异的39%至83%。性状变异主要由从湿冷气候到干暖夏季的温度梯度主导，同时亦受到湿度梯度的影响。随着气候向湿冷方向演变，云杉物种往往会被其他云杉类群替代，这类替代类群的针叶与种子更小，但种球与种鳞更大。回归分析结果显示，沿气候梯度云杉物种会依次发生替代，尽管种内观测到的趋势未必与整体趋势相一致。本研究涉及的云杉类群受气候驱动的替代现象，可通过系统发育信号较低的形态性状的种间变异得到良好体现。此类性状的种间变异主要由气候因子驱动。这些云杉物种在温度维度上的生态幅较窄，但在湿度梯度上的生态幅范围更广。