Grayson orbital industry.

SharkHunter wrote:Except there's not too many really good orbital sources for the most important elements: carbon, oxygen, and nitrogen. Of those, the oxygen part is probably the easiest, because it's the leftover from photosynthesis, which turns the carbon back into "life form" feed. But in a "counter grav" civilization, which I'd assume was not totally lost to Grayson, you'd bring up equal amounts of "stuff to feed stuff" as you brought back in foodstuffs, aka let's say your "sewage treatment facilities" are sucking off all the methane, bottling it and that's part of the cargo delivery to the orbiting farm, etc. Nitrogenous part, not sure because I'm not an organic chemist or farmer though. Biggest question I'd have would be about things like pollination, etc. for seed crops; I'd imagine that bees wouldn't really enjoy zero-gee, etc. all that much, and the planetary atmosphere seems pretty poisonous for pollinators.

Type-C asteroids have a lot of carbon, plus likely trapped water. Nitrogen is easy to extract from the atmosphere, though having to haul it into orbit would be painful.

SharkHunter wrote:Except there's not too many really good orbital sources for the most important elements: carbon, oxygen, and nitrogen. Of those, the oxygen part is probably the easiest, because it's the leftover from photosynthesis, which turns the carbon back into "life form" feed. But in a "counter grav" civilization, which I'd assume was not totally lost to Grayson, you'd bring up equal amounts of "stuff to feed stuff" as you brought back in foodstuffs, aka let's say your "sewage treatment facilities" are sucking off all the methane, bottling it and that's part of the cargo delivery to the orbiting farm, etc. Nitrogenous part, not sure because I'm not an organic chemist or farmer though. Biggest question I'd have would be about things like pollination, etc. for seed crops; I'd imagine that bees wouldn't really enjoy zero-gee, etc. all that much, and the planetary atmosphere seems pretty poisonous for pollinators.

Grayson had mining operations out in the comets. They had access to plenty of CHNO.

I'm beginning to suspect that not many of us are keen gardeners - or stock-rearing farmers. There's far more to creating soil than just mixing up a few elements and calling it 'job done'. For a start, you need the soil-dwelling organisms, worms or their equivalent, microrrhyza and all the other things that go to create fertile soil. Hydroponics are a start, but only a start and won't support intensive crops for long - you need actual soil of a fair depth. Ask anyone who's grown pot plants how much water and fertiliser they need, the multiply the answer by several hundred million acres to get enough produce for a planetary population.
Cheers
John

SWM wrote:

SharkHunter wrote:Except there's not too many really good orbital sources for the most important elements: carbon, oxygen, and nitrogen. Of those, the oxygen part is probably the easiest, because it's the leftover from photosynthesis, which turns the carbon back into "life form" feed. But in a "counter grav" civilization, which I'd assume was not totally lost to Grayson, you'd bring up equal amounts of "stuff to feed stuff" as you brought back in foodstuffs, aka let's say your "sewage treatment facilities" are sucking off all the methane, bottling it and that's part of the cargo delivery to the orbiting farm, etc. Nitrogenous part, not sure because I'm not an organic chemist or farmer though. Biggest question I'd have would be about things like pollination, etc. for seed crops; I'd imagine that bees wouldn't really enjoy zero-gee, etc. all that much, and the planetary atmosphere seems pretty poisonous for pollinators.

Grayson had mining operations out in the comets. They had access to plenty of CHNO.

John Prigent wrote:I'm beginning to suspect that not many of us are keen gardeners - or stock-rearing farmers. There's far more to creating soil than just mixing up a few elements and calling it 'job done'. For a start, you need the soil-dwelling organisms, worms or their equivalent, microrrhyza and all the other things that go to create fertile soil. Hydroponics are a start, but only a start and won't support intensive crops for long - you need actual soil of a fair depth. Ask anyone who's grown pot plants how much water and fertiliser they need, the multiply the answer by several hundred million acres to get enough produce for a planetary population.
Cheers
John

I was only responding to the statement that they could not get carbon, oxygen, and nitrogen from space mining. They can.

As for the rest of that, people already said that the organisms and such can come from the other existing orbital farms. Only the first farm needs to have that stuff decontaminated and hauled from the surface.

SWM wrote:As for the rest of that, people already said that the organisms and such can come from the other existing orbital farms. Only the first farm needs to have that stuff decontaminated and hauled from the surface.

There is also the point that "soil" from asteroids, comets, and other orbital habitats doesn't need decontamination; anything lifted from the planet does need decontamination.

Whatever chemical transformations are required to turn CHON into fertilizer, soil, and habitat structure would be small potatoes when compared to the cost of decontaminating and lifting the same elements from the surface.

John Prigent wrote:I'm beginning to suspect that not many of us are keen gardeners - or stock-rearing farmers. There's far more to creating soil than just mixing up a few elements and calling it 'job done'. For a start, you need the soil-dwelling organisms, worms or their equivalent, microrrhyza and all the other things that go to create fertile soil. Hydroponics are a start, but only a start and won't support intensive crops for long - you need actual soil of a fair depth. Ask anyone who's grown pot plants how much water and fertiliser they need, the multiply the answer by several hundred million acres to get enough produce for a planetary population.
Cheers
John

As far as I know, other than fungi family(includes moss), no plant needs what we think of as soil. A plants roots are for collecting 3 things. Minerals, water, and oxygen. Hydroponics can distribute all 3 of those very easily.

What IS soil? What makes up "GOOD" soil. Glad you asked. All good soil is, is a medium that holds water, allows oxygen to permeate it, and also holds freely available minerals. WHERE doe these minerals come from? They come from decomposing rock in the presence of oxygen. They come from the bacteria, roots breaking up the rock and freeing the nutrients. They also come from decomposing leaves etc from above(nitrogen/phosphorus generally).

Potted plants quickly eat the freely available nutrients and then have to break down the pebble matter for new nutrients. Since they are root bound compared to being in the ground, the amount of roots/bacteria they have is far less and therefore they cannot breakdown/free enough nutrients and the plant limits its growth.

Lets put it this way. Near 100% of young plants are started in hydroponics trays/bays in greenhouses and THEN transplanted into pots for selling to the general public. The Jack/Jill public only sees a young plant in a pot. You/They have no idea that those plants have only been in said pot a couple of months and the majority of their growth was attained in a hydroponics tray. This is especially true of all those woody stemmed plants that require cuttings to be taken verses seed. They then must be kept at a certain humidity otherwise it inhibits root growth or too much and they rot and do not grow at all.

Hydroponics in food production is already here for tomatoes/herbs. There are probably articles on tomato hydroponic growth.(real ones not the HEY! You can do it too! stuff) Hydroponic "towers" are sold to the general public through every gardening magazine. I believe there are huge greenhouses in California that grow tomatoes via hydroponics. Note via hydroponics this still means one must have a matt/moss mass at initial growing period so the fine roots can grow for oxygen. IE they cannot be drowned. So, Hydroponics does not mean NO 'soil' it just means next to none compared to what everyone thinks of rolling fields of barley, wheat, corn, etc.

Relax wrote:
Still that is a "TON" of orbital infrastructure. But not exactly an unthinkable amount.

The real question is: Where are they getting all of their C02?

-------------------

That's easy --
Planetary Greenhouse Gasses (I really didn't want to open this can of worms but I couldn't resist -- sorry)

-- Stewart

George J. Smith wrote:"Relax"]"John Prigent"]I'd like to know how much work went into lifting (millions of?) tons of decontaminated soil into orbit for those farms. It can't have been a minor effort, even over generations.
Cheers
John

Hydroponics. Do not need "soil". All you need is the minerals in solution form. Can get those from asteroids. Still, quite a few tons of minerals.[/quote]

But what do the cows eat that are in those orbital farms, IIRC they were "free-range" as it were in the "fields".[/quote]


--------------

They obviously ate Soylent Green......

-- Stewart

--snipping--

SWM wrote:

SharkHunter wrote:Except there's not too many really good orbital sources for the most important elements: carbon, oxygen, and nitrogen.
...

...
Grayson had mining operations out in the comets. They had access to plenty of CHNO.

On a tonnage basis, probably so, plus elemental hydrogen from Uriel. But you can bet that the best source is still planetary simply based on "freighter down with foodstuffs, freighter back up with "food fuel". Even if that food fuel is mostly in the form of gadzooks worth of frozen CO2. vs. chasing down and mining comets. I'd imagine that over a period of time, the Grayson's "agricultural commission" will have figured out what major elements are needed in what amounts(calcium being likely a major one) and the potash bunch, etc. that they need for the space born farms that isn't being um, spread by the orbiting cows..., and replenish that from best sources, asteroid, orbital, processed sewage, chicken eggshells, or whatever. Nature sort of takes care of the rest if the humans get those balances within strike range of optimally correct.

If you are shipping all that food down to the planet (in whatever form- raw, minimaly processed, fully processed) you are probably going to be shipping something to replace the weight in mateirals used back up. Human sewage (processed or not) would be a reasonable source of that material. You would have to process it at some point, if for nothing more than to kill pathogens that would othewise infect your growing medium (both hydroponic and "dirt" on the farms. You can do that with heat for part of the process, ultraviolet light for another, and also various special operations. Think of really large sewage treatment plants.

Very messy and hazardous job since so much of this will be in closed enviornments. Still, you would be bringing water and a lot of organic materials back up to the farms and if you process it there you are able to capture for use all that CO2 from the "composting" function ( plus the methane etc) to give the plants the carbon they need in a form they can use.

Of course, you are going to need all sorts of specialized equipment including anti-grave sealed tanks/containers and surface-to-orbit cargo vehicles to move all this organic material up to the farms and separate sets of at least the containers to move the food back down. Not a lot of people really want to spend any time thinking about just exactly what goes into dealing with human waste or ultimatly dealing with it after it is processed, particularly spreading that material on fields for food production.

Have you ever seen deliveries of "post consumption processed material" to farms for spreading on farmer's fields? Essentially you local sewage treatment plant takes all the organic material left over from the processing and sells it as fertilizer. There is some smell but not the same smell as the "raw" initial materials. Between the aeration (with constant sturing) and the heat generated as the material breaks down, most of the bacteria and other things that are problems for humans are killed.

I can't imagine a place like Grayson just taking millions of tons of the raw sewage and dumping it out into un-domed places. They really do need a place to put it. They have to work too hard to decontaminate planitary materials in the first place to throw away or recontaminate (with Grayson heavy metals etc) "human effluent". In a fusion reactor/anti-grave culture, the cost of moving essential the same amounts of materials up and down from the surface is relatively minor. Of course, nobody seems to have mentioned anyone working on the "Brown Shuttles"