Data from: New multicentury evidence for dispersal limitation during primary succession

Primary succession is limited both by ecosystem development and plant dispersal, but the extent to which dispersal constrains succession over the long term is unknown. We compared primary succession along two co-occurring arctic chronosequences with contrasting spatial scales: sorted circles that span a few m and may have few dispersal constraints; and glacial forelands that span several km and may have greater dispersal constraints. Dispersal constraints slowed primary succession by centuries: plots were dominated by cryptogamic soil after 20 years on circles, but after 270 years on forelands; plots supported deciduous plants after 100 years on circles, but after >400 years on forelands. Our study provides century-scale evidence suggesting that dispersal limitations constrain the rate of primary succession in glacial forelands.

原生演替（primary succession）同时受到生态系统发育与植物扩散两个因素的制约，但长期尺度下扩散约束对演替的影响程度仍未明确。我们针对两处共存且空间尺度差异显著的北极演替时间序列（chronosequence）展开对比研究：其一为跨度仅数米、扩散限制较弱的有序石环（sorted circles）；其二为跨度达数公里、扩散限制更强的冰川前缘（glacial forelands）。扩散限制使原生演替进程滞后数百年：石环样地在定植20年后便以隐花植物土壤（cryptogamic soil）为优势群落，而冰川前缘样地则需270年方能达到该状态；石环样地仅需100年即可支撑落叶植物（deciduous plants）定居，冰川前缘样地则需超过400年。本研究提供了百年尺度的实证证据，证实扩散限制会制约冰川前缘区域的原生演替速率。