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Lianas are taking over the rainforests, and it's visible from space

phys.org

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Re: Lianas are taking over the rainforests, and it's visible from space

#31

Post by vasco »

graemep wrote: post #28
vasco wrote: post #27

Earlier quoted context omitted.

> Given the dramatic damage he says it is doing in some areas, surely cutting them in at least those areas would make sense? You being personally convinced about something doesn't mean you can't be aware of your own limitations and want to be careful about implementing solutions too early to limit their impact of you're wrong. The difference is clear when you give an opinion about someone else's problems and how they…

Yes, but which is the lesser risk then? There seems to be a bias to do nothing rather than do something even if there are known benefits to doing something. There are definitely lots of consequences to lots of things we have done with regard to climate change and pollution. If we avoided everything with consequences the only action is do nothing. > The difference is clear when you give an opinion about someone else's…

> The global environment is everyone's problem, surely?

That's my point, it falls in the "you have to live with it" category.

Re: Lianas are taking over the rainforests, and it's visible from space

#32

Post by bregma »

padjo wrote: post #25
ekianjo wrote: post #22

> it's visible from space (phys.org) Misleading headline again (this is a pattern), they are not visible from space, they can be estimated based on satellite images using a complex model. That's not at all what common people understand by "visible".

Lots of things are visible from space, it’s just a question of magnification.

Zoom. Enhance.

Re: Lianas are taking over the rainforests, and it's visible from space

#33

Post by defrost »

ekianjo wrote: post #22

> it's visible from space (phys.org) Misleading headline again (this is a pattern), they are not visible from space, they can be estimated based on satellite images using a complex model. That's not at all what common people understand by "visible".

> they are not visible from space, they can be estimated based on satellite images using a complex model.

Much like a human brain estimates or imagines an image based on a complex model transformation of sensor data from various cones arrayed within the eyes.

Here we have a straightforward, readily pipelined, multispectral transformation that combines 'colours' from the non (human) visible part of the greater spectrum and creates a shifted blended colour image in the human eye visible part of the spectrum such that target vegetation is prominent.

In the remote sensing domain calling such things visible has been common parlance for three decades.

It's similar to that trope scene in action films that has a sniper using a thermal filter to enhance body heat for better target imaging.

Re: Lianas are taking over the rainforests, and it's visible from space

#34

Post by adrian_b »

graemep wrote: post #26

> "All plants grow faster with more CO₂, but lianas benefit even more." I have read other articles (by climate scientists) that say that the increase on CO₂ is not sufficient for this to be significant. > "We shouldn't intervene until we fully understand their ecological role" Given the dramatic damage he says it is doing in some areas, surely cutting them in at least those areas would make sense?

The effect depends on the plant and on its environment.

While more CO2 is good for plants, the associated changes in temperature and humidity can be bad and they can counterbalance the effect of increased CO2.

There has been a recently published study, for which I cannot remember a link, which has evaluated the current effects of the climate change for 7 major plant crops. For 3 of them, including rice, increased CO2 has resulted in higher productions, but for other 4, including maize, the associated changes in air temperature and humidity has determined lower productions, despite the higher availability of CO2.

Re: Lianas are taking over the rainforests, and it's visible from space

#35

Post by credit_guy »

bcraven wrote: post #3
verisimi wrote: post #2

> He attributes this to rising atmospheric CO₂ levels. "All plants grow faster with more CO₂, but lianas benefit even more And yet this extra growth all around because of co2 means that the will be more co2? This seems incoherent. Pet peeve - if the article hooks you with a line like 'visible from space' they should provide the imagery so I can see for myself. But there's no picture.

The previous paragraph explains it: >Lianas are rapidly expanding their territory in tropical forests, sometimes suppressing tree growth entirely in certain locations. In such areas, forest regeneration halts, and carbon storage can decline by as much as 95%. "That's almost equivalent to deforestation," Visser says. There's more more CO₂ in the atmosphere; so more lianas grow; they choke out the main tree body; so le…

Still, this does not sound right. You are hinting towards some predator-prey-type of cycle: trees grow (and absorb CO2), lianas infest them (and by the way, they appear to absorb even more CO2), but then trees die, and lianas die with them. But then won't trees grow again, and the cycle would repeat? Maybe overall, this cycle would reduce some CO2 absorption, but by 95%?

Re: Lianas are taking over the rainforests, and it's visible from space

#36

Post by bcraven »

credit_guy wrote: post #35
bcraven wrote: post #3

Earlier quoted context omitted.

The previous paragraph explains it: >Lianas are rapidly expanding their territory in tropical forests, sometimes suppressing tree growth entirely in certain locations. In such areas, forest regeneration halts, and carbon storage can decline by as much as 95%. "That's almost equivalent to deforestation," Visser says. There's more more CO₂ in the atmosphere; so more lianas grow; they choke out the main tree body; so le…

Still, this does not sound right. You are hinting towards some predator-prey-type of cycle: trees grow (and absorb CO2), lianas infest them (and by the way, they appear to absorb even more CO2), but then trees die, and lianas die with them. But then won't trees grow again, and the cycle would repeat? Maybe overall, this cycle would reduce some CO2 absorption, but by 95%?

There's some interesting results here[0] but from what I can make out the trees don't necessarily die and take the liana(s) with them. They may continue to stand (dead) or may simply be hugely starved of light.

[0]https://besjournals.onlinelibrary.wiley.com/doi/10.1111/j.13...

Re: Lianas are taking over the rainforests, and it's visible from space

#38

Post by globnomulous »

verisimi wrote: post #2

> He attributes this to rising atmospheric CO₂ levels. "All plants grow faster with more CO₂, but lianas benefit even more And yet this extra growth all around because of co2 means that the will be more co2? This seems incoherent. Pet peeve - if the article hooks you with a line like 'visible from space' they should provide the imagery so I can see for myself. But there's no picture.

> And yet this extra growth all around because of co2 means that the will be more co2? This seems incoherent.

It's not. Atmospheric CO2 increases as a result of processes external and unrelated to these forests. There's no suggestion or reason to think that plant growth would or could counteract that trend.

> Pet peeve - if the article hooks you with a line like 'visible from space' they should provide the imagery so I can see for myself. But there's no picture.

It would be nice, but I suspect it's missing for the same reason imagery is missing from so many astronomical articles, too: there aren't any images, because the findings are numerical and statistical, not visual.

The detection process that the article describes certainly sounds as thought it wouldn't be visible. To make the findings visible to readers of this article, the researcher would need to build it from effect, addin false color to an image to make it visible. And even then the differences may be too miniscule to be visible to the naked eye without considerable additional manipulation.

Those images likely don't exist, and creating them would be a lot of work for a probably small team of researchers who don't have a lot of extra labor or spare money.

Re: Lianas are taking over the rainforests, and it's visible from space

#39

Post by graemep »

adrian_b wrote: post #34
graemep wrote: post #26

> "All plants grow faster with more CO₂, but lianas benefit even more." I have read other articles (by climate scientists) that say that the increase on CO₂ is not sufficient for this to be significant. > "We shouldn't intervene until we fully understand their ecological role" Given the dramatic damage he says it is doing in some areas, surely cutting them in at least those areas would make sense?

The effect depends on the plant and on its environment. While more CO2 is good for plants, the associated changes in temperature and humidity can be bad and they can counterbalance the effect of increased CO2. There has been a recently published study, for which I cannot remember a link, which has evaluated the current effects of the climate change for 7 major plant crops. For 3 of them, including rice, increased CO2…

Those are for specific crops.

Presumably, if some crops become higher yielding (in a particular area) people will plant more of them so the next effect will be higher plant growth.

Similarly, in nature, plants that benefit most will spread, so the net effect will be higher plant growth.

SO overall we should have an increase in plant growth?

Re: Lianas are taking over the rainforests, and it's visible from space

#40

Post by ech0riginal »

quaintdev wrote: post #9

> The leaves that make lianas ultra-efficient reflect more light and infrared radiation than tree foliage. > "Tree leaves tilt, allowing light to reach lower neighbors—even the forest floor gets some sunlight. But lianas leave almost nothing for others." But that seems like a mechanism that could help reduce rising temperature

> But that seems like a mechanism that could help reduce rising temperature

Correct me if I’m wrong, but afaik higher reflection rates would exacerbate climate change, not help it. Absorbing that radiation kickstarts photosynthesis, which in turn uses captured CO2, therefore I’d expect the amount of sunlight reflected has a negatively inverse relationship with the amount of CO2 captured. I could very well be wrong, I’m not a biologist, but higher rates of both sunlight & CO2 capture seem ideal in this instance.

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