Wild bees thrive after severe forest fires


 
08 August 2017

published by https://phys.org


USA - Early results from a two-year study in southern Oregon suggest that moderate and severe forest fires create conditions that lead to greater abundance and diversity of wild bees.

Because Oregon's more than 500 species of native bees are important pollinators of wild plants and crops, the study suggests that fires may promote bee populations that in turn may influence agricultural productivity and overall floral diversity.

In 2016, scientists began trapping bees at 43 sites in forests burned by the 2013 Douglas Complex fire north of Grants Pass. The sites ranged from places where fire severity was low—flames were confined to low-growing vegetation and failed to reach the canopy—to places where severity was moderate and high.

"In low severity spots, if you weren't looking for the markers of fire, you wouldn't know that it had burned," said Sara M. Galbraith, a post-doctoral researcher in the College of Forestry at Oregon State University. "The canopy is completely closed, and the trees are usually older. There isn't a lot of evidence of fire except for some blackened areas on some of the tree trunks.

"And then, when you go to some of the high-severity fire sites, it's a completely open canopy. There are a lot of flowering plants in the understory because the light limitation is gone. It just looks completely different," she added.

In a study led by Jim Rivers, OSU forest wildlife ecologist, Galbraith and a team of field researchers collected bees with blue-vane traps, which attract the insects by reflecting ultra-violet light. "The bees basically think it's a huge flower," said Galbraith. "Once they get inside the trap, they are unable to fly out because of the shape of the entrance."

In addition, researchers recorded the characteristics of each site, such as the types of plants, the degree of forest cover and whether or not logging had taken place after the fire.

Such studies are important, Galbraith said, because the early stages of forest development—what researchers call early seral forests—have become less common. "This research adds to the evidence that there is high biodiversity in early seral forests relative to older stands, and moving forward, this could have an impact on services like pollination in the landscape overall. Without this fundamental information, we can't be sure of the best management actions to conserve pollinator populations within managed forests."

An international team of climate researchers from the US, South Korea and the UK has developed a new wildfire and drought prediction model for southwestern North America. Extending far beyond the current seasonal forecast, this study published in the journal Scientific Reports could benefit the economies with a variety of applications in agriculture, water management and forestry.

Over the past 15 years, California and neighboring regions have experienced heightened conditions and an increase in numbers with considerable impacts on human livelihoods, agriculture, and terrestrial ecosystems. This new research shows that in addition to a discernible contribution from natural forcings and human-induced global warming, the large-scale difference between Atlantic and Pacific ocean temperatures plays a fundamental role in causing droughts, and enhancing wildfire risks.

"Our results document that a combination of processes is at work. Through an ensemble modeling approach, we were able to show that without anthropogenic effects, the droughts in the southwestern United States would have been less severe," says co-author Axel Timmermann, Director of the newly founded IBS Center for Climate Physics, within the Institute for Basics Science (IBS), and Distinguished Professor at Pusan National University in South Korea. "By prescribing the effects of man-made climate change and observed global ocean temperatures, our model can reproduce the observed shifts in weather patterns and wildfire occurrences."



Read more at: https://phys.org/news/2017-07-atlanticpacific-ocean-temperature-difference-fuels.html#jCp
An international team of climate researchers from the US, South Korea and the UK has developed a new wildfire and drought prediction model for southwestern North America. Extending far beyond the current seasonal forecast, this study published in the journal Scientific Reports could benefit the economies with a variety of applications in agriculture, water management and forestry.
 

Over the past 15 years, California and neighboring regions have experienced heightened conditions and an increase in numbers with considerable impacts on human livelihoods, agriculture, and terrestrial ecosystems. This new research shows that in addition to a discernible contribution from natural forcings and human-induced global warming, the large-scale difference between Atlantic and Pacific ocean temperatures plays a fundamental role in causing droughts, and enhancing wildfire risks.

"Our results document that a combination of processes is at work. Through an ensemble modeling approach, we were able to show that without anthropogenic effects, the droughts in the southwestern United States would have been less severe," says co-author Axel Timmermann, Director of the newly founded IBS Center for Climate Physics, within the Institute for Basics Science (IBS), and Distinguished Professor at Pusan National University in South Korea. "By prescribing the effects of man-made climate change and observed global ocean temperatures, our model can reproduce the observed shifts in weather patterns and wildfire occurrences."



Read more at: https://phys.org/news/2017-07-atlanticpacific-ocean-temperature-difference-fuels.html#jCp