Written by: Nathaniel Tok, Peak Associate

 

Climate change causes plant community to change in Arctic regions

A study has found a relationship between the impact of climate change and the growth of new, taller plants in the Arctic and tundra regions. The research has also looked into how warming affects the community structures of cold weather ecosystems and plant traits.

The lead authors of the study, which has been published in Nature, included SFU biology professor David Hik as well as Isla Myers-Smith, Chancellor’s Fellow, University of Edinburgh, who is one of Hik’s former PhD students.

The worldwide study with more than 100 participating researchers found that climate warming helped plants grow taller at arctic or mountainous sites like in the Arctic, Alaskan, Canadian, Icelandic, Scandinavian, and Siberian mountains. This increase in plant height is projected to affect soil temperature, decomposition, and carbon cycling within the ecosystem. Shorter plant species did not appear to be affected by the rise of taller species.

The overall change of tundra plant communities might depend on how wet the tundra becomes. “Our study highlights the importance of accounting for future changes in water availability, as this will likely influence both the magnitude and direction of change for many traits,” noted Hik.

 

Temperature and salmon found to affect steelhead trout behaviour

On the Keogh River in northern Vancouver Island, SFU biology doctorate student Colin Bailey and biology professor John Reynolds have found that temperature and population levels of salmon, along with other conditions, will cause steelhead trout to alter their life cycle, size, and numbers.

Reynolds, who is also examining the status of plants and animals across Canada, believes the insights of the study will help efforts to conserve steelhead trout. For example, a large influx of salmon returning to the river system will cause steelhead trout to migrate to the sea sooner and more steelheads to breed in rivers. Bailey speculates that the spawning salmon lay eggs in the river, which are a potent and energy-rich food source for the juvenile steelheads.

However, Bailey admits the situation is complex, saying that “these fish seem to be controlled by many different factors at different times.”

For now, research will look at how size and age at entry to the sea affect steelhead life at sea. This research in turn will help researchers see if steelhead rearing conditions affect whether they can return and reproduce themselves.