Data from: Limited stand expansion by a long-lived conifer at a leading northern range edge, despite available habitat
Krapek, John; Buma, Brian (2018), Data from: Limited stand expansion by a long-lived conifer at a leading northern range edge, despite available habitat, Dryad, Dataset, https://doi.org/10.5061/dryad.7rd7s
1. In an era of rapid climate change, understanding the natural capacity of species’ ranges to track shifting climatic niches is a critical research and conservation need. Because species do not move across the landscape through empty space, but instead have to migrate through existing biotic communities, basic dispersal ecology and biotic interactions are important considerations beyond simple climate niche tracking.
2. Yellow-cedar (Callitropsis nootkatensis), a long-lived conifer of the North Pacific coastal temperate rainforest region, is thought to be undergoing a continued natural range expansion in southeast Alaska. At the same time, yellow-cedar’s trailing edge is approaching its leading edge in the region, due to climate-induced root injury leading to widespread mortality over the past century. To examine the current dispersal capacity of yellow-cedar at its leading range edge, and potential for the species’ leading edge to stay ahead of its trailing edge, we characterized recent yellow-cedar stand development near Juneau, Alaska, and surveyed the spread of yellow-cedar seedlings just beyond existing stand boundaries.
3. Despite suitable habitat beyond stand edges, stand expansion appears limited in recent decades to centuries. Large quantities of seed are germinating within stands and just beyond boundaries, but seedlings are not developing to maturity. Furthermore, ~100-200-year-old yellow-cedar trees are located abruptly at stand boundaries, indicating stand expansion is in a period of stasis with a last pulse at the end of the Little Ice Age climate period.
4. Vegetative regeneration is common across stands and may be an adaptive strategy for this long-lived tree to persist on the landscape until conditions are favorable for successful seedling recruitment, leading to an overall punctuated migration and colonization of new landscapes.
5. Synthesis. Species ranges do not always respond linearly to shifting climatic conditions. Instead, successful colonization of new habitat may be tied to episodic, threshold-related landscape phenomena, dispersal ability, and competition with existing plant communities.
National Science Foundation, Award: OIA-1208927