• dtc@lemmy.world
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    1 year ago

    So I think the general idea is that you can convert more CO² to carbon in the form of sugars and O² molecules per square foot with algae than with trees. Trees would totally do the same thing if we ripped up all the concrete and buildings to replant a forest, but that process would take decades.

    This can be added into existing infrastructure and helps I guess. Kinda a neat concept.

    • Nate@programming.dev
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      1 year ago

      …if we ripped up all the concrete and buildings to replant a forest…

      You say this like it’s a downside, we’d better get started!

      • dtc@lemmy.world
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        1 year ago

        Hey, I’d be the first wanker with a sledge out breaking it up if we all went in on it together. Something tells me I wouldn’t get very far tho

      • Eldritch@lemmy.world
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        1 year ago

        It would be. Cities and urban areas aren’t the problem. Suburbs, with 20+ Minute commutes, on hot swollen rivers of concrete and asphalt flowing from them, with every individual in their own metal/polymer box burning hydrocarbons is the bigger problem. Cities might be a solution.

        Conversely these algae tanks can go lots of places a tree wouldn’t be practical. They’ll never need to be trimmed out of power lines etc. Or tear up sidewalks, streets or foundations. That’s not to say we shouldn’t have trees. Just more green overall.

    • Touching_Grass@lemmy.world
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      1 year ago

      I have this fantasy where we humanity has a whole biotechnology skill tree that we never unlocked but there’s like a Renaissance waiting to happen that will one day uncover all these cool new branch’s

    • knorke3@lemm.ee
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      1 year ago

      also algae farms can be arbitrarily vertical and can be built underground if you supply them with CO2 - trees are mostly limited to the surface.

        • kase@lemmy.world
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          1 year ago

          On this note, think of all the benefits if we filled all our public swimming pools with algae!! I’m sure nobody would notice the difference

          • dtc@lemmy.world
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            1 year ago

            Honestly unless it was a red cyanobacteria bloom I doubt anyone would notice. I for one don’t drink pool water so I wouldn’t be very affected 🤷

    • Ottomateeverything@lemmy.world
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      But why not just like… Do that somewhere where the mass actually makes a difference? You’d be better off dumping acres full of this shit instead of regrowing a forest. Doing it in individual tanks, sparsely within a city, is both an inefficient use of resources and fucking ugly.

      Trees only purpose in a city is not to clean out CO2. It’s not even their primary purpose in a city. If it was, they’d be selecting specific species etc.

      • kase@lemmy.world
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        1 year ago

        Alright I’m just going off of what I learned in environmental science class this summer, not an expert here. There was something about algae blooms (usually caused by fertilizer runoff) being a really bad thing for local ecosystems. I’m not sure if this is relevant to what you’re saying, just throwing it out there lol

      • dtc@lemmy.world
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        1 year ago

        I mean ideally we would flood the ocean with Fe³ and spark a mass breed of this shit where it belongs. The biomass could work it’s way up the food chain as an added benefit too.

        But we won’t 🙃

        • FierySpectre@lemmy.world
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          1 year ago

          If history taught us anything it is that purposely messing with an ecosystem seldom has the effect we want to achieve.

          • dtc@lemmy.world
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            1 year ago

            Better to leave it with just the environmental changes we made without intent right?

            • Ottomateeverything@lemmy.world
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              1 year ago

              I mean, sort of?

              We created a big problem by injecting a lot of shit where it shouldn’t be. If we stop that, some pieces will bounce back.

              Injecting more shit in another place means we have one big problem, that we haven’t stopped, and now a new problem that we don’t know the repurcussions of or how to reverse.

              So uh, yeah, I’ll stick with the one beast we know over one we know and also another we don’t.

              • dtc@lemmy.world
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                1 year ago

                It’s okay to say you don’t understand marine chemistry, there is no shame in it.

                The whole “seed the oceans with ferrous oxide” idea isn’t mine. In fact many better minds came up with it. You can check it out if you want, no pressure.

            • FierySpectre@lemmy.world
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              It is much easier to destroy something than it is to repair it. This applies to the original changes we made through exploitation, pollution, etc. But also to the radical change you propose, it is much easier for it to have a destructive effect compared to having a positive effect.

              • dtc@lemmy.world
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                1 year ago

                I agree on the first part of what you said.

                But we aren’t fixing the problem either way so what’s really at stake?

    • subtext@lemmy.world
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      Pedantic, but for carbon dioxide or oxygen (or most other molecules you’ll write out) it’s a subscript for the number. Wikipedia

      ~So it would be CO~2~ or H~2~O or O~2~~

      Seems my markdown is rusty, however you make subscripts I guess for CO<sub>2</sub>

    • Doctor xNo@r.nf
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      If they didn’t just breath oxygen and give off CO² at night, maybe, but trees actually undo much of their oxygen creation overnight… 😅

  • TipRing@lemmy.world
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    While it’s good to be skeptical, algae tanks like this are actually a good idea for the use-cases for which they are designed. Places where trees would be difficult and expensive to grow. The tanks more efficiently capture carbon, require less maintenance, produce fertilizer as a byproduct and the solar panels on the tank produce enough extra power for there to be a USB charger on the bench. The goal isn’t to replace trees with tanks but to use them where it makes sense to do so.

    • ridethisbike@lemmy.world
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      This was my thought as well. They should be used in addition to, not as a replacement for, trees, bushes, and grass.

      It does make me wonder, though, whether or not we could use these to help capture more carbon than we’re creating.

      • Sanyanov@lemmy.world
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        1 year ago

        That would require a gigantic scale of operations, and trees are just waaaay more economical.

        Think of entire oceans full of algae not being enough to stop what’s currently going on with ecological situation.

    • Ann Archy@lemmy.world
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      Too expensive to grow trees? Thank god capitalism is saving us so much money, we are all so rich now that we can simply buy oxygen tanks instead of having to deal with those money sucking trees and plants.

  • leggettc18@programming.dev
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    1 year ago

    To echo what some other people have said, these algae tanks absolutely should not be used instead of trees. If I see a tree get chopped down and replaced with one of these, I’ll be sad and angry. However, these can go in places where trees can’t go, like rooftops. And you don’t have to either wait for a tree to grow for a decade or take a tree from somewhere else to install one. It also serves as both a seating area and can mount a solar panel on top. These and trees both have their place and should both continue to be used.

    • frezik@midwest.social
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      Putting a ton of water on the roof isn’t a good idea, unless it was already rated for a swimming pool.

      They don’t need to be inside cities at all.

  • EmperorHenry@discuss.tchncs.de
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    1 year ago

    Well Trees don’t make as much money for rich people who own everything and Trees make hot days more comfortable for homeless people

    • Madison420@lemmy.world
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      1 year ago

      Algea is a much much better oxygenator with lower maintainence, people don’t seem to notice how fast cities can kill trees.

      • frezik@midwest.social
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        You don’t need to put algae in cities. They can be basically anywhere to absorb CO2.

        Trees in cities tend to be carefully chosen for the environment. Are we in a climate where we need to put salt on the road in the winter? Choose trees that can tolerate some salt in the ground.

        • optissima@lemmy.ml
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          Maybe stop putting salt down in winter??? Who does that still they need to stop.

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            As much as it sucks, until we reduce the need for cars, northern rural areas are going to need to use salt for roads to be usable. Of course, if global warming gets worse it won’t be an issue

            • bufalo1973@lemmy.ml
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              1 year ago

              “Global warming” doesn’t mean warmer winters. It means extreme summers and winters and nothing in between, with a global temperature raising.

            • lad@programming.dev
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              Besides the already stated fact that global warming will only make winters worse, there are better ways like cleaning the snow (ok, that’s radical) or using abrasives like sand or gravel.

              • eltimablo@kbin.social
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                Clearing the snow doesn’t fix the ice that snowplows leave behind and gravel/sand is a straight placebo. That’s why the roads get salted/brined.

      • evranch@lemmy.ca
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        And the oceans are incredibly vast, so they provide most of the world’s oxygen! Obviously it’s hard to get a precise number but 50-70% is the accepted range.

        There are many reasons to plant trees in the city but local oxygen supply isn’t one of them. Mostly trees look nice, and make people feel better by their presence. They also have a significant cooling effect, something a steamy tank full of warm algae definitely won’t help with on a summer day.

        • Madison420@lemmy.world
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          Local oxygenation is important, conversion at the source pretty much always is.

          Moreover it doesn’t at all imply in lue of trees and importantly oxygenate at the same rate day and night since they’re independently lit ideally 24/7/365.

    • Honytawk@lemmy.zip
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      I think it has more to do with the fact trees require more maintenance, like raking up leaves and fruit, and having to saw off branches.

      Also those roots can break pavement and pipes.

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        You really think those massive, experimental water tanks won’t require more maintenance, because you have to trim trees once ever few years? Or because their roots might grow too much?

        • zalgotext
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          Ok, I like trees as much as the next person, and much prefer them over these algae tanks.

          But what about these “massive experimental water tanks” do you think will damage the infrastructure beneath and around it like tree roots do?

      • EmperorHenry@discuss.tchncs.de
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        Well of course, you can’t give working class people any money for working, you can only give them a slave-wage. That’s why all manufacturing was outsourced to very underdeveloped countries when NAFTA was first put into place.

        You can easily get away with exploiting people who have no other choice but to work for a dollar per year, but it’s much more difficult to do that to someone’s neighbor in their community.

    • Octopus1348@lemy.lol
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      We just have to remove the roof from that thing so it won’t be shadowy, and make a wall in the bottom so it can’t be used to lay down.

  • grue@lemmy.world
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    Street trees aren’t car-supremacist enough.

    Let me explain what I mean by that: when a driver fucks up and his car careens off the street and hits a tree, the tree stops the car very abruptly. That’s great for, say, an innocent pedestrian who was saved by hiding behind the tree, but can apply rather serious consequences to the negligent driver. Car-brained traffic engineers see it as their mission to protect drivers from any and all consequences, so they insist on ripping out all the trees to create a gigantic “clear zone” so that the car is free to careen wherever it wants without hitting anything solid. Squishy things within the clear zone, such as pedestrians, don’t enter into consideration.

    In other words, one important “advantage” of these “liquid trees” over real trees is that they can be mounted on breakaway stands, so that they yield (and therefore provide no protection to any hapless bastard who might’ve been sitting on the bench at the time) when a car hits them.

    Source: I’m a former traffic engineer. But don’t take it from me; watch this confession from a much more experienced and credible engineer explaining it in even more stark terms.

    • Honytawk@lemmy.zip
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      Is that why there are so many metal poles next to roads?

      Sounds to me like that is a US-centric issue.

  • gerbler@lemmy.world
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    I think a lot of these are just cool experiments and projects grad students do for the sake of doing them. Then some hack writes an op ed about how we don’t need to worry about deforestation because we can plop algae tanks down instead.

    • Baphomet_The_Blasphemer@lemmy.world
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      I thought it was more of an experiment that, if proven successful, could eventually aid in the exploration of space since we would need to engineer ways of creating oxygen for prolonged travel.

    • WetBeardHairs@lemmy.ml
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      Oh thank god. We don’t have to worry about deforestation anymore? Phew. Thanks, tank of algae.

      • Ann Archy@lemmy.world
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        Sadly, dealgaeation is quickly becoming a catastrophic problem. However, we are confident we can soon genetically modify human lungs to partially breathe the sulphur clouds that will engulf our planet!

  • Bamboodpanda@lemmy.world
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    It’s sad that the effort to do something innovative to solve a problem can easily get dismissed via a zero effort critique by someone who never took the time to learn why it was created.

    • sciencesebi@feddit.ro
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      Yeah…most of the O2 comes from plankton. People seem to freak out about a few trees being cut down, but are chill when it comes to rising ocean temps

    • BCsven@lemmy.ca
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      There is a tree right next to it. LOL so obviously space for trees. The trunks take up less space, its just they require pulling up surrounding sidewalk sometimes, and maintenance crew for trimming and watering in dry spells.

      • DrDominate@lemmy.world
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        Trees don’t perform nearly as much work as the algae tank in sucking up C02 and outputting 02, require more maintenance, and takes longer to deploy (have to wait for tree to mature).

  • TAG@lemmy.world
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    Trees are great on sidewalks, but it is much easier to control the weight of an algae tank if you want to make a green roof for a building.

  • RememberTheApollo_@lemmy.world
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    Trees offer real world benefits of carbon reduction, temperature reduction, shade for people, the psychological benefits that trees offer, some limited wildlife habitat, and they do it without much outside help. They grow themselves with decent maintenance.

    But you have to build and maintain this tank. What carbon was used to do so, and what maintenance will it need. Can it offset its own cost? It offers no benefits to wildlife, no shade, no temperature reduction.

    Yeah, trees leave leaf litter and can heave sidewalks with roots, but given that neither system is perfect, there’s no reason to argue that boxes of algae are better.

    • Ook the Librarian@lemmy.world
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      Why do we need to argue which is better? In some places, beautification isn’t really practical, but you can still stick these around. They don’t look hard to install or uninstall, unlike trees.

      I would hate to see a tree actually replaced by one these. But no one but the meme is saying that is the plan.

      • Ann Archy@lemmy.world
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        I think we have reached the limit for how much we should “improve” and replace nature, if there’s no room for trees we should make room instead of accomodating yet another industrial solution to a problem created by industry in the first place.

        We’re going in the wrong direction.

        • Meowoem
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          So you’re a climate change denier? You don’t think we need to worry about co2 levels?

          Or is this just a knee jerk unthought responce because you hate science and technology?

    • uis@lemmy.world
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      carbon reduction

      Mostly indirect.

      Also trees dampen noise

      Can it offset its own cost?

      I guess.

      there’s no reason to argue that boxes of algae are better.

      Depends on metric of choice. Still I would prefer trees.

  • CoffeeJunkie@lemmy.world
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    I’d have to see how it is better than, worse than trees on a case-by-case basis. But generally speaking, I can think of a few reasons this is better:

    Trees are messy. They take a long time to grow, they take constant maintenance while growing, then they eventually die. Tree roots fuck up pipes & concrete. If this installation is equivalent to 1 or more trees, it is doing the work in a fraction of the space.

    • HiddenLayer5@lemmy.ml
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      It’s expensive and has only the advantage of catching CO2

      It doesn’t even do that well. Algae have short lifespans and when they decompose, the CO2 will go right back into the atmosphere. It’s the same reason you can’t reasonably capture CO2 with small plants like grasses, nor does the carbon inside you count as captured. The reason trees “capture CO2” is because trees live for a long time and wood decomposes very slowly, and therefore keep its carbon locked in the wood for a long time. The point of capturing carbon is you take it out of circulation for as long as possible.

      There are ways to have algae capture carbon, but they are fairly involved (read: very expensive) processes whose scalability is still uncertain. Certainly not a tank in the street.

      • Flumsy@feddit.de
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        I was always under the impression that plants chemically convert CO2 and some other stuff to glucose (C6-H12-O6), right? In that case, the algae would still help, wouldnt they?

        • HiddenLayer5@lemmy.ml
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          It helps if and only if the glucose stays as glucose and is not metabolized. Wood is a good application of this, as its cellulose fibers are made of glucose, in a form that is very stable and can stay locked away for a long time (especially if the tree is alive as it does not metabolize the glucose in its own wood and has anti-predation adaptations that actively guard it against other organisms). However, if the glucose decomposes, i.e. is metabolized, it is converted either directly to CO2 or into other compounds that eventually end up as CO2, essentially returning the captured carbon back to the atmosphere.

    • Gabu@lemmy.ml
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      Humans really are weird. Trying to replace a perfectly fine bio-machinery that developed over Thousands of years with their own steel junk. I dont see why anybody would prefer that gadget over a tree.

      Can you plant a tree capable of capturing the same amount of CO2 as those algae in that small a space? How about “refilling” the tree if it happens to die?

      Society doesn’t have to lock itself to a single solution for countless varied problems. If we’re talking about a long, empty walkway, or a park, then trees are a great solution. If we’re talking about a small space that must be kept free of obstructions, such as a bus stop, then a sack or box of phytoplankton is much better suited.

      • HiddenLayer5@lemmy.ml
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        I assume they mean how long many old growth forests have been growing (though even then thousands of years is on the younger end), not the time it took for trees to evolve.

    • stranger@lemm.ee
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      What happens when we go too far and remove all CO2 from the atmosphere?

      • Gabu@lemmy.ml
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        Your question isn’t entirely a hypothetical - this happened at the dawn of time, when photosynthetic life forms first evolved. First, it won’t ever happen again, no matter how good we get at scooping CO2 from the atmosphere. Second, the result is theoretically catastrophic for aerobic life forms, but it’s also a negative feedback loop, meaning it self corrects.

      • Karyoplasma@discuss.tchncs.de
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        Most plants would die because they rely on CO2 for photosynthesis.

        Many sea animals would die. Oceans absorb CO2 which forms carbonic acid (H2CO3) in water. Oceans are slightly alkaline due to dissolved salts (bicarbonate and carbonate) and the carbonic acid from the absorption helps to create a stable pH. Many sea animals are highly adapted to a specific pH and would die if the ocean got either too acidic or too alkaline, so they are pretty doomed in either case.

        Many humans would die because agriculture would collapse. Also breathing pure oxygen over a long period of time would be very bad because of oxygen toxicity. Yeah, pure oxygen is toxic for humans lol

        Land animals, I’m not so sure, but I assume most of them would die too.

    • grue@lemmy.world
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      Nobody uses an urban tree that gets cut down. It just gets hauled off to the landfill.

      It’s absolutely ludicrous that when the gigantic oak in my yard fell the arborist didn’t know of anybody who could cut it up into lumber for me – even in a city with so many urban trees that it’s called the “city in a forest” – but allegedly the economics of it don’t work out, or something. I dunno if that’s true, but it pisses me off enough that I’m half-tempted to go buy a damn portable sawmill and start a business doing it myself.

      • FierySpectre@lemmy.world
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        Say that to the table in my living room. (They removed a lot of old exotic trees that were lining some road some years back, those trees got sold to people making nice tables).

        Selling the trees was only a side effect, and these weren’t your run of the mill trees either. But exceptions exist

    • DrDominate@lemmy.world
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      That is super cool and my immediate assumptions were dispelled. I would love to see these in my city.

    • MeatsOfRage@lemmy.world
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      Thanks for posting this! I was curious about this and had to scroll through so many miserable comments in this thread to find this.

      • eltimablo@kbin.social
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        For real, the people on this site deserve the hell they create for each other. If Kbin had a functioning account delete button, I’d have been gone months ago.

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    1 year ago

    Guys, it’s not one or the other. We can have trees and algae tanks. Trees can still offer all of the benefits they do like shade and beauty while algae tanks can be used to increase fresh oxygen. Algae is much better at absorbing CO2 than trees and providing clean air which is a big problem in a busy city.

    • explodicle@local106.com
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      1 year ago

      It is one or the other because they’ll come out of the same budget - it’s an “opportunity cost”. So if the city has $1000 to spend on either a tree or a tank, then they can’t spend the same $1000 on both items. We’d need some balance between the two.