Ocean Farming: Seaweed is having its moment in the sun | Hacker News Reader

Ocean Farming: Seaweed is having its moment in the sun

nytimes.com

88 pointslxm45 comments

http://web.archive.org/web/20230318024611/https://www.nytime...

Using seaweed as a natural fertilizer has been known about for a long long time, and seaweed "farming" has been occurring since at least the 70's [1].

The farming in this case is less "planting new crops" and more "harvesting crops that already exist in the wild, in a sustainable way."

Coastal communities where I grew up would regularly collect washed-up seaweed, and then bury it in the garden.

But as the article points out, while the properties of seaweed are well known in some places, to most Americans it's a pretty unknown resource.

[1] https://kelpakusa.com/

Indeed. There's a number of related videos on yt as well.

This is a total new arena where we can mess the environment with little or no restrictions and get something for free that we can peddle as a green alternative. Sounds promising!

Seaweed has been used as a fertilizer in Scotland for thousands of years. It's hardly new.

I've been interested in the cattle feed angle for a while now, as it does 2 things: produces sustainable cattle feed which reduces reliance on continued productivity of land (can keep same cows/acre without artificial nitrogen inputs), and the reduced Methane output reduces the emissions of each animal such that continued production doesn't fall afoul of regulators.

Also, here in Ireland there is such a thing as Folio rights [1], inherited rights to collect seaweed from the foreshore, much like turbary rights, the right to cut turf from a certain plot of common land. Unless you are already in possession of these, getting licensed for seaweed harvesting is likely to be a headache.

[1]: https://www.seaweed.ie/irish_seaweed_contacts/

Kinda curious, are the plastics removed from the seaweed before consumption or there is not a process to get rid of the small particles?

I don't know, but that is something worth considering with all the seaweed uses

Imagine the possibilities for domesticated marine plants..

There don’t seem to be any truly domesticated species, though it’s arguable. Here are two great sources on the topic:

https://www.sciencedirect.com/science/article/abs/pii/S00652...

https://nph.onlinelibrary.wiley.com/doi/10.1111/nph.13278#:~...

See also Greenwave https://www.greenwave.org/

> GreenWave’s 10-year goal is to provide training, tools, and support to a baseline of 10,000 farmers to catalyze the planting of regenerative ocean crops and yield meaningful economic and climate impacts.

It's kind of gnarly: there's nothing visible from the surface except for some buoys. There are chains running from the buoys to the seafloor, and food (oysters or mussels or whatever) grows all along the chain, seaweed too.

The thing is: no inputs.

No fertilizer, no irrigation, nothing.

You set it up, monitor it, then harvest.

This is one of those things that makes so much sense that it's almost unbelievable.

I've eaten seaweeds before in several formats, and they're surprisingly versatile. But they're "further out there" than kale, so I appreciate that the nytimes didn't want to push that angle.

And, in case you're wondering "heavy metals bio-accumulate in ocean fish to questionable levels; could heavy metals bio-accumulate in seaweed to a dangerous level?", tl;dr: probably not to dangerous levels, but not certain.

"Distribution of metals and metalloids in dried seaweeds and health risk to population in southeastern China"[0]:

> Concern about metals and metalloids, especially heavy metals in seaweeds has risen due to potential health risk. This study investigated the distribution of 10 metals and metalloids in 295 dried seaweeds (brown and red) and estimated the possible health risk via hazard index (HI). > ... > The estimate of health risk showed that there was low health risk for potential toxic elements by intake of these seaweeds.

(I've gotta say, that article doesn't seem entirely convincing. This is probably the first article of this format I've read before, so I might be totally off-base, but the error bars in their data[1] are huge. Given that the article literally has "health risk to population in southeastern China" in the title, I'm skeptical whether the article is intentional fluff/propaganda science.)

[0]: https://www.nature.com/articles/s41598-018-21732-z (full text) [1]: https://www.nature.com/articles/s41598-018-21732-z/tables/2 (data)

Consumer labs has done studies and shown excessive heavy metals from around the world. In fact I’ve never seen a seaweed in CA that doesn’t contain a prop 65 logo on it.

My push lawnmower has a Prop 65 warning label on it.

It likely contains lead or some other prop 65 chemical. I wish the warnings were a bit better and more contextual, but it maybe that your lawnmower turns bits of its heavy metals into dust you could breathe in, which is dangerous.

The ubiquity of prop 65 doesn’t mean the issue is with prop 65 warnings - the problem is the ubiquitous use of heavy metals and other nasty chemicals in manufacturing. Worse, most places don’t have such a warning so people have no idea.

I was in H-Mart last weekend and the amount of food with prop 65 was quite disturbing. A lot of it grown in Asia in areas with heavy lead contamination. They have no such warnings there.

Wood dust was added to the list in 2010, and therefore, all wood products sold in California must bear the Prop 65 warning.

At some point, it really is about the ubiquity of the warnings making them virtually useless. I think we’re past that point.

It is very important for people who are sanding or working with wood products to not inhale that directly, and instead take proper precautions. When you say wood products, I’m assuming you mean that in its raw form versus a finished table, which will not carry such a warning.

The lesson isn’t that their ubiquity doesn’t mean they’re useless; it’s that as a society we’ve allowed too much toxicity into our lives. I don’t know what percent of prop 65 warnings are for things like wood where it’s about the dust, but I do wish the warnings were improved to give specific actionable information. Like “hey wood dust shouldn’t get into your lungs. Make sure to wear a mask with certification X to prevent that”.

Do you have the link to the levels?

My understanding is that it depends a lot on the type of seaweed and where it is grown.

Here’s the article; the levels are behind a paywall (which I subscribe to - ConsumerLab is fantastic): https://www.consumerlab.com/news/metals-in-seaweed-snacks/12...

I don’t want to copy their copyrighted material to the open web. Perhaps it’s been summarized elsewhere but they give an overview. The levels were different by location, but everywhere had at least one bad level (arsenic, lead, iodine, cadmium, etc).

Yeah, I found that but couldn't find the levels. I found a larger study on pubmed that seemed to have more mixed results based on the species and location.

It’s extremely unlikely because the accumulation tends to happen in top-of-foodchain fish. When fish eat fish that eat fish that eat fish, there can we quite a bit of accumulation. Smaller fish tend to be safer. I’d imagine that plants at the bottom of the foodchain would be very safe.

This was what I was going to say, my only contribution will be to add i was taught this mechanism was called ecologic magnification, but apparently in wikipedia it's refferred to as biological magnification[0], so, some term drift in 20 years perhaps

[0]https://en.wikipedia.org/wiki/Biomagnification

> But they're "further out there" than kale

I'm curious about this. I've seen kale being vaguely mentioned here and there, but I don't know its, for lack of a better word, cultural significance.

What is this all about?

Their seen as a liberal, left-wing food. Right-wingers will say something like "Those kale eating liberals."

Kale is a nutrient rich leafy green food in the same family as broccoli. A lot of people seem to hate the flavor, I don't mind it and I wonder if it's because I ate a lot of broccoli as a kid (didn't have any kale until decades later).

For some reason, in America, there's a cultural association with healthy food (especially if it isn't meat based) and left-wing political progressives. I think that is also playing a part here, as there's an implication that the progressive left-wing NYT would be interested in publishing more healthy food propaganda and otherwise "telling people how to live."

Thank you for the context.

> For some reason, in America, there's a cultural association with healthy food (especially if it isn't meat based) and left-wing political progressives.

I would never get used to this level of political divide. Was it always like that?

> Was it always like that?

Since at least the '80s, and probably way further back than that.

There has been a lot happening in Norway in the last five years when it comes to farming kelp. The industry is still in its infancy, but I know one company that have invested toward expanding production toward 100,000 mtn.

It's a lot of exciting new problems to handle though. How do you conserve biomass, preventing it from rotting without using excessive energy. Kelp is high in iodine, so for human consumption how do you get it out? Labor is very expensive, so how do automate seed production and harvesting? And how do you find a market and ship the product there?

>"Pierre Paslier [...] wanted to create packaging that would come from nature and disappear into nature, quickly. With a friend from graduate school, Rodrigo García González, he created a company called NotPla, short for “not plastic.”

From an East London warehouse, they designed an edible sachet of water, made of seaweed and other plant extracts: To drink the water you simply pop the sachet in your mouth. They designed another one that can hold ketchup and a third for cosmetics."

There would seem to be a large market for non-plastic easily biodegradable waterproof containers (for whatever product) -- made from seaweed...

Related: https://www.notpla.com/

> But can seaweed thrive in a warming world?

Apparently so.[1]

[1] https://www.cnn.com/travel/article/seaweed-sargassum-florida...

Absolutely mounds of it rotting away on the beaches in Barbados.

I think it's worth noting that you would never forage/collect seaweed that's been washed up on the shore, since 1. you don't know how far along it is in terms of decomposing 2. The water quality of where it grew

So I am not sure this is a valid argument unless you were trying to imply that clearly seaweed is still growing. But one point in time says nothing about a possible trend

While the oceans are warming, well, you're right and wrong. The amount of seaweed has been increasing, but it has nothing to do with warming oceans.[1]

[1] https://www.reuters.com/world/americas/scientists-come-close...

If you wanted to mitigate excessive atmospheric carbon, use bio carbon capture and sequestration. And where's the most logical place to do that? The ocean, as either phytoplankton or kelp or both.

Fish. And plankton. Sea greens. And protein from the sea.

The giant kelp forests of California 90% died in the past decade. They were sequestering the equivalent of $1.5B worth of carbon per year. The geography is such that the kelp would grow and get sucked down into the deep sea each year.

If it were possible to regenerate this forest, who should get the money? Is there a way that the ecosystem itself could have a trust to ensure it’s long term ecological viability?

https://www.nature.org/en-us/newsroom/ca-sunflower-sea-star-...

The kelp forest itself sells carbon credits and uses that money for other mitigations ?

(I'm fully aware carbon credits are nonsense).

I don’t think governments recognizes ecological entities. There would have to be some legal trust or something that sought the money, which could be in trust for ecological wellbeing.

Plankton. Sea greens. And protein from the sea.

Lot of things are having their moment lately

seaweed is the new GPT?

Let's wait for Seaweed-5

I heard kelp can compete at 1200 elo chess rating

There are decades where nothing happens and there are weeks when decades happen.

Counter-productive loading graphic: so good that you don't want to scroll down to the actual content.

From the article:

[picture of a laundry pod] (caption)" Edible bubbles designed to replace single-use packs for liquids. Ellie Smith for The New York Times"

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