Environment & Energy
Related: About this forumCalifornia Forests Not Growing Back After Extreme Fires; Study In 10 National Forests Across State
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After studying 14 burned areas across 10 national forests in California, scientists from UC Davis and the U.S. Forest Service said recent fires have killed so many mature, seed-producing trees across such large areas that the forests can't re-seed themselves. And because of increasingly warm temperatures, burned areas are quickly overgrown by shrubs, which can prevent trees from taking root.
"With high-severity fires, the seed source drops off," said study co-author Kevin Lynch, a forest researcher at UC Davis. "We aren't seeing the conditions that are likely to promote natural regeneration."
Historically, severe fires were uncommon in the forests covered by the study, largely made up of yellow pines and mixed conifers, but extended drought and heatwaves have exacerbated fire conditions across the West. The changing climate is also seen as a factor in recent wildfires in the Southeast, which is also mired in drought.
For the study, published Wednesday in the journal Ecosphere, the researchers surveyed 1,500 plots in burned areas at different elevations in the Sierra Nevadas, Klamath Mountains, and North Coast regions. There was no natural conifer regeneration at all in 43 percent of the plots, they reported. "[O]ur data support growing concern that the well-documented trend toward larger and more severe fires is a major threat to conifer forest sustainability in our study region," the authors wrote. They said the study results could apply to mixed conifer forests across the West.
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https://insideclimatenews.org/news/21122016/california-forests-wildfires-climate-change
CrispyQ
(36,446 posts)I am stunned at how in-the-sand humanity's head is.
jeffreyi
(1,938 posts)2nd author my former coworker
Well done.
OKIsItJustMe
(19,937 posts)[font size=4]New Tool Helps Foresters Prioritize Restoration Efforts[/font]
By Kat Kerlin on December 21, 2016 in Environment
[font size=3]A study spanning 10 national forests and 14 burned areas in California found that conifer seedlings were found in less than 60 percent of the study areas five to seven years after fire. Of the nearly 1,500 plots surveyed, 43 percent showed no natural conifer regeneration at all.
The study was co-led by UC Davis and the USDA Forest Service and published December 21 in the journal Ecosphere. It presents a tool to help foresters prioritize which lands to replant immediately after a fire, and which lands they can expect to regrow naturally.
High-severity fires are knocking out seed sources and leading to a natural regeneration bottleneck, which poses a predicament for the sustainability of our forests, said lead author Kevin Welch, a research associate with the UC Davis Department of Plant Sciences.
For example, 10 of the 14 burned areas in the study, which include well-known wildfires like the Moonlight (2007) and Power (2009) fires, did not meet Forest Service stocking density thresholds for mixed conifer forests, making them good candidates for replanting and restoration efforts.
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