Ecological Overshoot

Discussion in 'Science and Technology' started by Ricter, Nov 23, 2021.

  1. Cuddles

    Cuddles

    couldn't finish reading it. Not sure if parody like the onion.
     
    #321     Mar 13, 2023
  2. Ricter

    Ricter


    • Climate is changing too quickly for the Sierra Nevada's 'zombie forests'

      March 13, 20235:06 AM ET
      Joe Hernandez

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      Young giant sequoia trees are seen during a prescribed pile burning on Feb. 19 in Sequoia National Forest. Researchers say 20% of Sierra Nevada conifers are a mismatch with their climate.Mario Tama/Getty Images

      Some of the tall, stately trees that have grown up in California's Sierra Nevada are no longer compatible with the climate they live in, new research has shown.

      Hotter, drier conditions driven by climate changein the mountain range have made certain regions once hospitable to conifers — such as sequoia, ponderosa pine and Douglas fir — an environmental mismatch for the cone-bearing trees.

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      A single fire killed thousands of sequoias. Scientists are racing to save the rest

      "They were exactly where we expected them to be, kind of along the lower-elevation, warmer and drier edges of the conifer forests in the Sierras," Avery Hill, who worked on the study as a graduate student at Stanford University, told NPR.

      Although there are conifers in those areas now, Hill and other researchers suggested that as the trees die out, they'll be replaced with other types of vegetation better suited to the environmental conditions.

      The team estimated that about 20% of all Sierra Nevada conifer trees in California are no longer compatible with the climate around themand are in danger of disappearing. They dubbed these trees "zombie forests."

      The environment is changing faster than the trees can adapt
      The team scrutinized vegetation data dating back to the 1930s, when all Sierra Nevada conifers were growing in appropriate climate conditions. Now, four out of five do.

      That change is largely due to higher temperatures and less rainfall in these lower-elevation areas, as well as human activities, such as logging, and an uptick in wildfires.

      The Sierra Nevada conifers aren't standing still. The average elevation of the trees has increased over the past 90 years, moving 112 feet upslope. According to Hill, that's because lower-elevation conifers have died while conifers at higher elevations where the air is cooler have been able to grow.

      But the conifers' uphill trek hasn't been able to keep pace with the dramatic increase in temperatures. The researchers said the number of Sierra Nevada conifers incompatible with their environments could double in the next 77 years.

      The new maps can inform forest conservation and management plans
      But Hill, who is now a postdoctoral researcher at the California Academy of Sciences, hopes that the maps he and his colleagues developed showing the state's "zombie forests" will help shape people's understanding of the effects of climate change.

      "Conservationists know, scientists know, so many people know that ecosystems are changing and expect them to change more, and people are grappling with this," he said.

      "These maps are unique, in that you can put your finger on a point and say, 'This area right here is expected to transition due to climate change in the near future,' and this forces some really difficult questions about what we want this land managed for and do we try to resist these impending changes," Hill added.
     
    #322     Mar 13, 2023
  3. Ricter

    Ricter

    Low Sacramento River salmon forecast to close California ocean salmon fishing statewide

    Damon Arthur, Redding Record Searchlight
    Sun, March 12, 2023 at 3:51 PM MDT·3 min read

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    Winter-run juvenile Chinook salmon are prepared for release at Coleman National Fish Hatchery in March 2018. (Photo: Steve Martarano/U.S. Fish and Wildlife Service)

    Federal officials have proposed closing commercial chinook salmon fishing off the coast of California over concerns for expected low numbers of fall-run chinook salmon returning to the Sacramento River this year.

    The Pacific Fishery Management Council announced its three alternatives for recreational and commercial fishing Friday.

    Ocean recreational fishing from the Oregon-California border to the U.S.-Mexico border will be closed in all three proposals, "given the low abundance forecasts for both Klamath and Sacramento River fall chinook." the council said in a news release issued Friday.

    Commercial salmon fishing off the coast of California also will be closed, the council said. Ocean fishing restrictions were also announced for Oregon and Washington.

    “The 2023 salmon season discussions have been dominated by the severely low forecasts for both the Klamath and Sacramento River fall Chinook stocks”, said council Executive Director Merrick Burden, “The Council will need to deliberate on the best path forward in setting 2023 seasons with considerations for economic implications to the coastal communities and the low abundances of key salmon stocks and the need to ensure future generations of healthy salmon returns.”

    The council meets again from April 1-7 to consult with scientists, hear public comment, revise preliminary decisions, and choose a final alternative at its meeting, the council said.

    The management council's decisions only affect ocean fishing seasons. The California Fish and Game Commission will approve salmon seasons and regulations for inland streams and rivers in early April, state officials said.

    The Golden State Salmon Association said the fishing closure will have a devastating effect on commercial fishing companies and other businesses that serve them.

    "Our local commercial and recreational fleets are devastated,” said Bay Area commercial salmon troller Sarah Bates. “Those of us that depend on salmon have lost our livelihoods completely this year, and potentially next year. Aside from the economic impacts to our ports, communities and families, we are heartbroken at the condition of our ecosystems and frustrated at the colossal mismanagement of our public water resources."

    At a meeting held earlier this month, state and federal officials forecast one of the lowest adult fall-run chinook salmon population estimates since 2008, according to the California Department of Fish and Wildlife.

    The fall-run chinook is considered the predominant species of salmon in freshwater and ocean fisheries, the state said. This year, the state forecast 169,767 adults in the population.

    Out of the four chinook salmon species that spawn in the Sacramento River and its tributaries, the fall-run is the largest. Most of the fish that return to the Shasta-Tehama county stretch of the river are hatched at Coleman National Fish Hatchery south of Anderson.

    The salmon spawn in freshwater or inland fish hatcheries, migrate to the ocean, where they usually live for three years and then return to rivers and streams to spawn and die.

    Most of this year's adults were born in 2020. That year about 12.4 million hatchery-raised salmon were released from Coleman. There also are other fish hatcheries in the state that produce fall-run chinook.

    Klamath River chinook salmon numbers are also very low. State officials said they expect 103,793 Klamath River chinook, which represents the lowest numbers since 1997.

    Reporter Damon Arthur welcomes story tips at 530-338-8834, by email at damon.arthur@redding.com and on Twitter at @damonarthur_RS. Help local journalism thrive by subscribing today.

    This article originally appeared on Redding Record Searchlight: Low Sacramento River salmon forecast to close ocean salmon fishing
     
    #323     Mar 13, 2023
  4. Ricter

    Ricter

    You must understand that the economy has never, does not now, and will never exist independently of the planet's stock of resources (both inputs and sinks). The processes are actually one process.
     
    #324     Mar 13, 2023
  5. Cuddles

    Cuddles

    sure, but by that logic anything and everything on earth is about global warming.
     
    #325     Mar 13, 2023
  6. Ricter

    Ricter

    Of course global warming has an effect on everything, but ecological overshoot is the overall problem. Details to be found... here in this thread. :)

    For me, the best way to organize my understanding has been the nine boundary model. Climate change just seems to come up much more, though I do try to bring articles that address the other impacts.
     
    #326     Mar 13, 2023
  7. Ricter

    Ricter

    [​IMG]
     
    #327     Mar 15, 2023
  8. Ricter

    Ricter

    Deforestation 'fast outstripping' regrowth, say Bristol scientists
    Published 23 hours ago

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    Image source, Viola Heinrich Image caption,The study also found that one third of forests degraded by logging or fire, were later completely deforested

    Recovering tropical forests offset just a quarter of carbon emissions generated each year by logging, wildfire and land clearing, new research has found.

    The study, led by University of Bristol scientists, found destruction of these ecosystems currently far outstripped the pace of regrowth.

    Working with an international team, they used satellite data to study the world's three largest tropical forests.

    They hope it can inform decisions about protecting these areas.

    The study was the first to estimate aboveground carbon absorption in tropical forests recovering from degradation and deforestation, said lead author, Dr Viola Heinrich, who gained her PhD in physical geography at Bristol University.

    "While protecting ancient tropical forests remains the priority, we demonstrate the value in sustainably managing forest areas that can recover from human disturbances," she said.

    Brazil's National Institute for Space Research took part in the study of Amazon, Central Africa and Borneo forests, published in Nature.

    Scientists found areas recovering from human disturbances, such as logging; as well as forests re-growing in previously deforested areas, were annually removing at least 107 million tonnes from the atmosphere.

    However, the total amount of carbon being taken up in aboveground forest re-growth was only enough to counterbalance 26% of the current carbon emissions from tropical deforestation and degradation.

    Emphasising the vulnerability of the carbon sink in recovering forests, the team also found one third of forests degraded by logging or fire were later completely deforested.

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    Image source, Regrow Borneo Image caption,The team looked at three of the world's largest tropical rainforests, including in Borneo
    "The carbon recovery models we developed can inform scientists and policy makers on the carbon storage potential of secondary and degraded forests if they are protected and allowed to recover," said Dr Heinrich.

    'Time running out'
    She added tropical forests, which provide vital resources for millions of people and animals, needed to be protected and restored "for their carbon and climate value" but also on a local scale, "people need to be allowed to continue to use" them sustainably.

    Co-author Dr Jo House said countries had repeatedly pledged to reduce deforestation and restore areas, which were the "most cost-effective and immediately available way" to remove carbon from the atmosphere - but targets were "repeatedly missed".

    "Our research demonstrates that time is running out," Dr House added.

    A South-South alliance to protect rainforests was forged by Brazil, Indonesia, and Congo at COP27 last November.

    https://www.bbc.com/news/uk-england-bristol-64956535
     
    #328     Mar 16, 2023
  9. Ricter

    Ricter

    [​IMG]
     
    #329     Mar 16, 2023
  10. wildchild

    wildchild

    Wildchild nails it again.
     
    #330     Mar 16, 2023