中国拥有世界上最丰富的裸子植物区系, 对理解全球裸子植物分布变化与系统演化具有重要意义。我们利用中国天然分布的202种裸子植物的水平和垂直分布信息获得物种分布区范围, 探讨了中国裸子植物在科、属、种水平的分布特点。总体上, 中国裸子植物物种丰富度南高北低, 山地裸子植物丰富度较高, 平原和高原相对贫乏; 随分类阶元变高, 丰富度高值区域面积逐渐扩大, 高值中心逐渐南移。占中国陆地面积5%的裸子植物最丰富区域内分布了85%的中国自然分布的裸子植物物种。我们将这些区域划分为6个裸子植物多样性中心: (1)东喜马拉雅—横断山脉—秦岭, (2)滇黔桂–南岭, (3)华中山地, (4)黄山—武夷山脉, (5)海南岛南部山地, (6)长白山(甑峰山附近)。各中心裸子植物区系之间的特点和联系反映了各自地理位置的差异和空间距离的隔离作用, 其中横断山脉地区是中国裸子植物最重要的分化中心。

China has the richest flora of gymnosperm in the world, which is crucial for understanding the change of global distribution and phylogeny of gymnosperm. We mapped the geographical range of 202 native gymnosperm species in China with records of altitudinal range and horizontal distribution at the county level, and explored the spatial distribution characteristics of Chinese gymnosperm at the family, genus and species levels. The uniqueness and similarity among the richness centers were analyzed with respect to their gymnosperm family and genus composition, and the endemism. Generally, Chinese gymnosperm shows a decreasing trend of richness from south to north. The richness is high in mountainous areas and low in large plains and on large plateaus. From the species, genus to family levels, the area with high gymnosperm richness increases, and the center with high richness shifts southward. About 85% of all Chinese gymnosperm species are harbored in just 5% of Chinese land area. We classified these regions into six richness centers: (1) Eastern Himalaya-Hengduan Mountains-Qinling Mountains; (2) joint area of Yunnan-Guizhou-Guangxi and the South Mountain Ranges; (3) central China mountains; (4) Huangshan-Wuyi Mountains; (5) southern mountains of Hainan Island; and (6) central part of Changbai Mountains. The floristic relationship of gymnosperm among the centers is obviously related with their geographic location, and the effect of isolation by distance. Among the six centers, Hengduan Mountains is a major variation center of gymnosperm in China.