[HN Gopher] Researchers are scaling up solar-powered kelp farms
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       Researchers are scaling up solar-powered kelp farms
        
       Author : geox
       Score  : 60 points
       Date   : 2023-12-25 13:03 UTC (1 days ago)
        
 (HTM) web link (spectrum.ieee.org)
 (TXT) w3m dump (spectrum.ieee.org)
        
       | trebligdivad wrote:
       | I love the quote 'we've gone from designing systems on a chip in
       | Silicon Valley to systems on a ship'
        
         | schiffern wrote:
         | I had the opposite reaction. Reading that quote made me
         | immediately take them a lot less seriously.
         | 
         | It smacks of the same old SV overconfidence. " _I designed
         | (hold your applause) chips. How hard could maritime engineering
         | possibly be??_ "
        
           | bamboozled wrote:
           | Who cares, if it gets results, that's all that matters.
           | 
           | We really need results right now.
        
       | cmrdporcupine wrote:
       | Pretty cool, but...
       | 
       | The article " _Kelp is the planet's fastest-growing plant_ "
       | 
       | ... kelp is not a plant? Second sentence of its Wikipedia
       | article.
        
         | mkaic wrote:
         | Prescriptivism vs. descriptivism. Taxonomically, you're right
         | -- kelp is a macroalgae, not a plant. But _most_ people don 't
         | really care (and don't _need_ to care) about this taxonomical
         | distinction in their day-to-day life. It has a stem and leaves,
         | it eats via photosynthesis, it 's rooted to a single spot, and
         | it's green-ish -- as far as I'm concerned, that's a plant!
         | 
         | I generally find that defining words descriptively (based on
         | how most people use them most of the time) rather than
         | prescriptively (based on how institutions or niche groups use
         | them) is a good way to avoid conflict, both on the internet and
         | IRL!
        
           | SubiculumCode wrote:
           | The same with trees and 'plants'. Many trees are more closely
           | related to plants, than to other trees.
        
             | xen2xen1 wrote:
             | There are trees that aren't plants?
        
               | tomrod wrote:
               | I think they missed a word: other plants.
               | 
               | Tree wood has evolved independently several times, much
               | like the crab form.
        
       | patall wrote:
       | Too bad the article doesn't cover the relationship with nutrient
       | depletion. After all, nutrients taken up by their kelp won't make
       | other algae grow. Given that ocean fertilization experiments have
       | such big, unknown consequences (so that they are pretty much
       | under memorandum), that would have been interesting to relate to.
        
         | worik wrote:
         | Is that a problem?
         | 
         | What is the evidence?
        
         | balderdash wrote:
         | I'd speculate that if you did these offshore of river deltas
         | where there is significant agrarian economy upstream you'd be
         | able to capture fertilizer/waste run off, though not sure about
         | the distance to deep water and dissipation at that distance
        
       | adolph wrote:
       | Jokes on the downvoters who thought kelp couldn't turn sunlight
       | into biofuel.
       | 
       | https://news.ycombinator.com/item?id=37885853
        
         | asdff wrote:
         | That user was quite bullheaded it seems, claiming such things
         | are impossible without even understanding how kelp are grown
         | today. They are grown on lines trawled by ships, not the ocean
         | floor where there are urchins perhaps and depth requirements.
         | Its already a massive industry in East Asia. It's the US that
         | is decades behind on this effort. 16 million tons of seaweed
         | harvested in 2016 in these countries:
         | 
         | https://www.tandfonline.com/doi/full/10.1080/00318884.2019.1...
        
           | adolph wrote:
           | It is interesting how a cultural element, like food habits
           | leading to development of aqueous agriculture, can guide
           | later utilization of the resource in an unforeseen manner.
        
       | RetroTechie wrote:
       | Hmm..
       | 
       |  _" A quarter of the seaweed grown typically falls off the
       | platform and sinks 1,000 meters to the seafloor, von Herzen says.
       | At such depths, little oxygen is present, and biomass doesn't
       | readily decompose."_
       | 
       | Let's hope that is thoroughly verified. Elsewhere, microbes break
       | down biomass in oxygen-poor conditions into lots of methane. If
       | that turns out to be the case, dropping masses of seaweed to the
       | ocean floor could be a timebomb worse than the CO2 it
       | sequestered.
       | 
       | Better aim for the other option:
       | 
       |  _" But he [Rod Fujita] believes the best strategy for mitigating
       | climate change with seaweed is to turn it into fuels or plastics,
       | construction materials, or additives that suppress methane
       | emissions from cattle and rice paddies."_
       | 
       | Yep. Win-win: sequester carbon, and produce something useful that
       | replaces fossil-based goods.
        
         | asdff wrote:
         | This exact mechanism has been proved before in the historical
         | record, several times in fact, leading to ice ages even with
         | the massive sequestration of greenhouse gasses from such algae
         | falling to the bottom of the ocean.
         | 
         | https://www.wired.com/2012/07/algae-ice-age-climate/
        
           | andrewflnr wrote:
           | Yes, both mechanisms are well attested. We need to know which
           | one is happening here.
        
         | asdff wrote:
         | Also I apologize for the double comment but I think its a point
         | that stands on its own. Kelp is also very useful for dealing
         | with eutrification from either sewer or runoff. There have been
         | some successful pilot experiments in new york harbor on using
         | kelp to clean the water (1). Where its farmed in bulk it also
         | has significant cleaning properties for local waterways (2). So
         | not only does it help with greenhouse emissions but water
         | pollution as well.
         | 
         | 1.
         | 
         | https://www.thecity.nyc/2023/03/22/kelp-farming-climate-solu...
         | 
         | 2.
         | 
         | https://iopscience.iop.org/article/10.1088/1748-9326/ac3fd9
        
         | downrightmike wrote:
         | If we want to do anything to reduce carbon, we have to stop
         | burning shit, not just burn some other shit.
        
       | photochemsyn wrote:
       | Interesting project, the key take away is that if kelp can
       | migrate to deeper water overnight, they have access to nutrients
       | that typically end up depleted in the surface water.
       | Oceanography-wise, this is not surprising - spring algal blooms
       | in northern oceans are aided by winter storms mixing up the ocean
       | surface and introducing nutrients from deeper waters. However,
       | the climate blurb is a bit odd:
       | 
       | > "The extra kelp can be turned into food, fertilizer, and fuel,
       | or it can be committed to the deep, locking away countless tonnes
       | of carbon for centuries."
       | 
       | If you dump lots of organic carbon in the deep ocean, you end up
       | with a lot of microbial respiration of that carbon (return to
       | CO2) with an equivalent drawdown of free oxygen, leading to
       | anoxic bottom waters (a process exacerbated by all the nitrogen
       | fertilizer being dumped in the ocean from industrial
       | agriculture).
       | 
       | Hence, schemes like providing carbon credits to seaweed farmers
       | who dump their product in the deep ocean in exchange for the
       | ability to sell those carbon credits to say natural gas producers
       | who want to claim their emissions are being 'offset' should be
       | viewed as the dishonest scams that they are.
        
         | worik wrote:
         | Carbon credits are a scam, true
         | 
         | But I do not think it is a foregone conclusion that "...If you
         | dump lots of organic carbon in the deep ocean, you end up with
         | a lot of microbial respiration of that carbon (return to CO2)
         | with an equivalent drawdown of free oxygen,"
         | 
         | Have you evidence?
        
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       (page generated 2023-12-26 23:02 UTC)