The effect of climate change on phenology and growth is less understood for belowground plant tissues than for aboveground plant tissues, particularly in high-latitude regions. Ecotypes within a species adapted to a locality may display different responses to climate change.

We established two common garden plots in the Arctic tundra north of the Brooks Range in northern Alaska. Three ecotypes of Eriophorum vaginatum along a latitudinal gradient were transplanted into common gardens, and half of the transplants were warmed using open-top chambers (OTCs). Minirhizotrons were used to track the root phenology during the growing seasons of 2016 and 2017.

Warming with OTCs (approximately +1 °C in air) did not affect the root biomass, root production or root phenology. The southern ecotype (from 67°16′N) of Eriophorum vaginatum transplanted northward experienced delayed startup and root production compared to two northern ecotypes (from 68°38′N and 69°25′N), although significant differences were not observed in the three ecotypes in terms of root production, root biomass and growth duration at the two sites. Our results suggest that as the climate warms, ecotypes of Eriophorum vaginatum may be able to adjust their duration of root growth and root productivity by phenotypic plasticity, although the degree of plasticity controlling the root startup time may vary between southern and northern ecotypes.

与地上植物组织相比，人们对气候变化对地下植物组织物候和生长的影响的了解较少，尤其是在高纬度地区。适应当地的物种内的生态型可能对气候变化表现出不同的反应。

我们在阿拉斯加北部布鲁克斯山脉以北的北极苔原上建立了两个常见的花园地块。将沿纬度梯度的三种生态型Eriophorum vaginatum移植到普通花园中，并使用开顶室 (OTC) 对一半的移植物进行加热。Minirhizotrons 用于追踪 2016 年和 2017 年生长季节的根系物候。

用 OTC 加热（空气中大约 +1 °C）不会影响根生物量、根生产或根物候。与两个北方生态型（来自 68°38'N 和 69°25'N）相比，向北移植的Eriophorum vaginatum的南部生态型（来自 67°16'N）经历了启动和生根延迟，尽管在两个地点在根系产量、根系生物量和生长持续时间方面的三种生态型。我们的研究结果表明，随着气候变暖，Eriophorum vaginatum 的生态型可能能够通过表型可塑性来调整其根系生长的持续时间和根系生产力，尽管控制根启动时间的可塑性程度可能因南部和北部生态型而异。