biofouling or biogardening?
November 22, 2009 at 10:05 am #1118
In some places barnacles are considered a delicacy. Kelp and algea are a highly nutritious resource. Easy to solve a problem, when you see it as a potential solution. In this instance, it is a source of food, and construction materials. Shells crushed, make calcium carbonate, the main component of cement. For ferrocement, the plant life, such as kelp or algea, can be used as the reinforcing material.
Addressing statements from the book:
"Biofouling has a number of negative consequences. Barnacles increase drag (from moving, or from currents while anchored), which creates additional structural stresses. Some secrete corrosive acids which are concentrated because they are trapped in the area under the barnacle. They make it difficult to inspect or to re-coat a surface, both of which are very important in the harsh ocean environment."
let's address these incrementally, a step at a time. "Barnacles increase drag (from moving, or from currents while anchored), which creates additional structural stresses."
"from moving" A seastead as envisioned spends most of it's time in one place. If moving is desired, the seagarden can be cleaned up. "from currents while anchored" These seasteads out past the underwater coastlines, are unlikely to be ground anchored. whereas seaanchors typically cause less 'structural stresses' and so are relatively safe.
"Some secrete corrosive acids which are concentrated because they are trapped in the area under the barnacle They make it difficult to inspect or to re-coat a surface, both of which are very important in the harsh ocean environment."
To solve this there can be an extra hull layer. a sacrificial wooden exterior with cement undercoat for example
this depending on wood variety and seasteading location, can take a long time (decades) to rot away. It's also relatively easy to add on to, as new wood can be nailed or attached in some way. Another option may be to have a serrated surface. which allows for water to dilute the excreted acid. When a layer of biota dies, and leaves their shells, they actually add a protective layer, being dead they no longer excrete acid. The biogarden can develop several layers, new biota can attach itself to pre-existing biota. In fact, to increase the surface area for kelp or biota forests to grow, can have horizontal nets between the pillars or hulls. even perhaps extending outwards from the seastead. these nets can be detached or raised for easier movement or harvest. they might even act as a breakwater, allowing for swiming within the biogarden, being more effective with increased biomass.
Also of course we must remember, nature is beautiful and aesthetically pleasing, as are underwater biogardens.November 22, 2009 at 4:35 pm #8731
I agree. In past threads the “problem” of cleaning the hull of a seastead in the middle of the ocean was disscused (and debated). What is known as “bottom growth” in boating lingo (and reffered by you as “biogarden”) might not neccesry be so bad for a seastead, in comparison to a regular ship. As you said, since a seastead will move (if mobile) @ lower speeds than any other ship (it is fair to assume 3-4 knt crusing speed) than the bottom growth wont create such a drag to really make a big difference in terms of fuel consumption.It might turn actually beneficial for the seastead to “carry” this biogarden ecosistem along the way, since small fish will feed off the seaweed attached to the hull. If you have small fish than you will have bigger fish which feed on the small fish. That means dinner is served:-). Also, mussels, clams, oysters, crabs, seaweed, etc can be harvested of the bottom growth. If a seastead is big enough, this type of “aquaculture” would not only represent a source of free food for the seasteaders, but turn profitable in the long run. Personaly, I would let it grow and also “plant” coral on the bottom. Given that the hull if ferrocement and the seastead will sail in tropical warm waters I would try to turn the bottom into a coral garden. I ran into this amazing video regarding restoring the coral reef in Fiji. The same thing will work on a seastead’s bottom.
OctavianNovember 22, 2009 at 8:15 pm #8733
That was a fascinating video! The Truly fascinating part is that the organizers were able to get the locals to invest in what is obviously a long term project. As I recall, a good many of the pacific islanders made their livings by ‘dynamite’ fishing with recovered WWII ordinance which was how they destroyed the reefs to start with… One point though: I don’t think coral would grow on the underside of a seastead. Not only is it ‘dark’, it would be upside down. Those racks though, suspended in bigger racks like xnsdvd’s fish farm could be a way to go…
Elspru, welcome aboard by the way!November 23, 2009 at 11:07 pm #8736
We’re right! Didnt think of that,…
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