4 ms·

Does anyone know if we are facing similar ecological collapse on land?

vkou 4y ago
We've already caused it. The overwhelming majority of land mammal mass is either humans, or farm animals raised for humans to eat. Almost half of the world's land surface is now farmland.
- ThrowawayIP 4y ago
  And the vast vast majority of this farmland that could be used to raise human-edible crops is used to feed domesticated animals. While humans die of starvation.
- colechristensen 4y ago
  > Almost half of the world's land surface is now farmland This is a BS statistic meant to shock and inappropriately counts the entire area of wilderness that might be used for grazing which is just wilderness that would have supported similar animals anyway.
  - vkou 4y ago
    Managed crop monoculture, which ~half of farmland is - is not 'something similar' to natural forests, plains, grasslands, scrubland, etc. Even grazing land rarely looks anything like it does before we've shaped it for our use. And even when it does, at first glance, it gets a monoculture of animals, instead. Farmers are not keen on seeing their herds deal with competition or predation from the wild.
    - PeterisP 4y ago
      On the other hand, we have local biodiversity regulations which require certain land to be grazed and/or cut (as for hay), since the 'meadow' biomes and the associated birds and insects have adapted to the many centuries of land being farmed and can't survive if the plains aren't grazed and are left to just grow.
    - randomdata 4y ago
      > Managed crop monoculture, which ~half of farmland is That doesn't seem right. According to the FAO (United Nations), only 1.3 billion hectares of land are arable while nearly 5 billion hectares are used for agriculture. That's more like ~25%. And the latter figure only accounts for 38% of the world's land area, so the earlier half figure claim doesn't seem right either. I suppose if the margin of error on those approximations is exceptionally large...
    - deleted 4y ago
      [deleted]
- divbzero 4y ago
  That fits the estimates from one research article: [1] 0.06 Gt C human biomass 0.1 Gt C livestock biomass 0.007 Gt C wild mammal biomass 0.002 Gt C wild bird biomass The article also estimated that “wild land mammal biomass decreased ≈7.6-fold” when comparing the world today to prehuman times [2]. [1]: https://www.pnas.org/doi/10.1073/pnas.1711842115 https://www.pnas.org/doi/10.1073/pnas.1711842115 [2]: https://github.com/milo-lab/biomass_distribution/blob/master/animals/chordates/wild_mammals/wild_mammal.ipynb https://github.com/milo-lab/biomass_distribution/blob/master...
colechristensen 4y ago
We don’t eat land predators, generally, and most of the biomass lots happened much earlier with the spread of humans, i.e. 500 to 20,000 years ago. Most of the worlds land megafauna are gone because big slow things are really easy to kill for groups of primitive humans with pointy sticks.
- chucksta 4y ago
  There are certainly more recent records.. https://www.businessinsider.com/skulls-photo-american-bison-extinction-history-2016-4 https://www.businessinsider.com/skulls-photo-american-bison-... >In 1800, it was estimated there were forty million bison, by 1883, there were few wild bison in the United States - most were in Yellowstone National Park. By 1900, there were less than a thousand left in North America.
makerofspoons 4y ago
Yes, unfortunately: More than 75 percent decline over 27 years in total flying insect biomass in protected areas: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0185809 https://journals.plos.org/plosone/article?id=10.1371/journal... 48% of bird species in decline: https://news.cornell.edu/stories/2022/05/global-bird-populations-steadily-decline https://news.cornell.edu/stories/2022/05/global-bird-populat... among other examples. In 2018 it was estimated by the WWF that 60% of the animal population was lost between 1970 and 2014: https://www.wwf.org.uk/updates/living-planet-report-2018 https://www.wwf.org.uk/updates/living-planet-report-2018
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blakesley 4y ago
Err, what? You're not aware that we're destroying the planet? https://en.wikipedia.org/wiki/Holocene_extinction https://en.wikipedia.org/wiki/Holocene_extinction
- moistly 4y ago
  It absolutely boggles my mind that people can be unaware that this world is collapsing. One would have to deliberately avoid the media. Or, I guess, just shut the information out. “Too scary to think about” might be quite literal.

vkou 4y ago

We've already caused it. The overwhelming majority of land mammal mass is either humans, or farm animals raised for humans to eat. Almost half of the world's land surface is now farmland.

ThrowawayIP 4y ago
And the vast vast majority of this farmland that could be used to raise human-edible crops is used to feed domesticated animals. While humans die of starvation.
colechristensen 4y ago
> Almost half of the world's land surface is now farmland This is a BS statistic meant to shock and inappropriately counts the entire area of wilderness that might be used for grazing which is just wilderness that would have supported similar animals anyway.
- vkou 4y ago
  Managed crop monoculture, which ~half of farmland is - is not 'something similar' to natural forests, plains, grasslands, scrubland, etc. Even grazing land rarely looks anything like it does before we've shaped it for our use. And even when it does, at first glance, it gets a monoculture of animals, instead. Farmers are not keen on seeing their herds deal with competition or predation from the wild.
  - PeterisP 4y ago
    On the other hand, we have local biodiversity regulations which require certain land to be grazed and/or cut (as for hay), since the 'meadow' biomes and the associated birds and insects have adapted to the many centuries of land being farmed and can't survive if the plains aren't grazed and are left to just grow.
  - randomdata 4y ago
    > Managed crop monoculture, which ~half of farmland is That doesn't seem right. According to the FAO (United Nations), only 1.3 billion hectares of land are arable while nearly 5 billion hectares are used for agriculture. That's more like ~25%. And the latter figure only accounts for 38% of the world's land area, so the earlier half figure claim doesn't seem right either. I suppose if the margin of error on those approximations is exceptionally large...
  - deleted 4y ago
    [deleted]
divbzero 4y ago
That fits the estimates from one research article: [1] 0.06 Gt C human biomass 0.1 Gt C livestock biomass 0.007 Gt C wild mammal biomass 0.002 Gt C wild bird biomass The article also estimated that “wild land mammal biomass decreased ≈7.6-fold” when comparing the world today to prehuman times [2]. [1]: https://www.pnas.org/doi/10.1073/pnas.1711842115 https://www.pnas.org/doi/10.1073/pnas.1711842115 [2]: https://github.com/milo-lab/biomass_distribution/blob/master/animals/chordates/wild_mammals/wild_mammal.ipynb https://github.com/milo-lab/biomass_distribution/blob/master...

colechristensen 4y ago

We don’t eat land predators, generally, and most of the biomass lots happened much earlier with the spread of humans, i.e. 500 to 20,000 years ago. Most of the worlds land megafauna are gone because big slow things are really easy to kill for groups of primitive humans with pointy sticks.

chucksta 4y ago
There are certainly more recent records.. https://www.businessinsider.com/skulls-photo-american-bison-extinction-history-2016-4 https://www.businessinsider.com/skulls-photo-american-bison-... >In 1800, it was estimated there were forty million bison, by 1883, there were few wild bison in the United States - most were in Yellowstone National Park. By 1900, there were less than a thousand left in North America.

makerofspoons 4y ago

Yes, unfortunately: More than 75 percent decline over 27 years in total flying insect biomass in protected areas: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0185809 https://journals.plos.org/plosone/article?id=10.1371/journal... 48% of bird species in decline: https://news.cornell.edu/stories/2022/05/global-bird-populations-steadily-decline https://news.cornell.edu/stories/2022/05/global-bird-populat... among other examples. In 2018 it was estimated by the WWF that 60% of the animal population was lost between 1970 and 2014: https://www.wwf.org.uk/updates/living-planet-report-2018 https://www.wwf.org.uk/updates/living-planet-report-2018

deleted 4y ago

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blakesley 4y ago

Err, what? You're not aware that we're destroying the planet? https://en.wikipedia.org/wiki/Holocene_extinction https://en.wikipedia.org/wiki/Holocene_extinction

moistly 4y ago
It absolutely boggles my mind that people can be unaware that this world is collapsing. One would have to deliberately avoid the media. Or, I guess, just shut the information out. “Too scary to think about” might be quite literal.