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Simple Formula To Feed The World?


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The following caught my eye: wondering what you all think of it?

 

I spent a little over 10 years working in the pig industry, and while I focused on environmental issues, I spent plenty of time around very smart nutritionists.  

After dropping out of my PhD, I took a one year placement with Australia’s largest pig producer, nominally to write up a master’s. I was surprised to find they had four PhDs on staff and conducted over $2 million worth of research each year.

Pig nutritionists can formulate a diet around whatever source of carbohydrates and fats is cheapest, usually along with industrially produced amino acids, vitamins and minerals.

I know a lot less about poultry production and even less about aquaculture. However, I understand that silver carp tastes divine, and the feed conversion rates for these creatures is less than two to one, with minimal greenhouse gas emissions.

Since the 1990s, enormous progress has been made in understanding how to sustainably integrate the waste from intensive animal production into agriculture. I played a small role in this journey.

The key environmental challenge with intensive animal production is the quantity of nutrients that require careful management. This should not be counted as a negative, however, when the problem we face is feeding 10 billion people!

The manure and effluent by-products of intensive animal production and aquaculture are ideal for anaerobic digestion. This process converts much of the organic matter into methane and liberates the nutrients into the liquid phase. The methane can be burnt to generate heat and power. The nutrients can be shandied for fertigation into intensive horticulture. If the horticulture is undertaken in glasshouses then the ‘waste heat’ and CO2 rich exhaust gases can be used to further increase yields.

So there you have it.

Grow microalgae in the dry arid regions of the world where there is either sea water or non-potable water available for aquaculture ponds. Solar dry the biomass for transport to the peri-urban fringe. Formulate the microalgae with agricultural bio-products, vitamins and amino acids as required. Grow pigs, chickens and fish. Anaerobically digest the manures on site and fertigate the effluent into glass houses. Hey presto—10 billion people fed generously, with a system that is highly adaptable to future changes in the climate.

 

 

http://www.abc.net.au/radionational/programs/ockhamsrazor/overpopulation-and-the-10-billion-person-question/4889816

 

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I have little to offer in this discussion other than my personal experience.  Nitrogen is and seems to forever be my limiting factor.  Since ammonia production from hydrocarbon sources is so easy, this isn't an issue with nearly any other producer.  But the one factor I find in common with all of these silver bullet recycling schemes seems to me to be an absolute refusal to deal with the Nitrogen problem.  When I hear anaerobic I hear Nitrogen loss.  This is a fact of nature.  There are numerous schemes available to make effluent more marketable.  Water weight is a huge issue when you take in shipping costs.  Numerous well meaning plans try to carbonize waste, or to concentrate nutrients.  But if you can't retain Nitrogen, then I'm not interested.

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I genuinely thought phosphorus was the biggest issue? Nitrogen can be manufactured using Haber Bosch. Enough cheap energy from GenIV nuclear-waste-and-warhead eating nukes, and you can have all the nitrogen you need. Phosphorus, however, really needs to be recovered from our sewerage otherwise it is a mineral on a one-way trip to the bottom of the sea.

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We grow enough food to feed the world - that's not an issue. We grow enough variety of food to feed the world, and feed everybody ell - that's not an issue. It's entirely an issue of desire and logistics. No amount of growing food in the US is going to make it easier to get food into warzones, or navigate the intricate political arenas of local governments that are wary (and rightfully so) of outside help being used as a trojan horse. And how many farmers want to grow their crops and then not be compensated for them? (or be compensated well below market value?)

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I genuinely thought phosphorus was the biggest issue? Nitrogen can be manufactured using Haber Bosch. Enough cheap energy from GenIV nuclear-waste-and-warhead eating nukes, and you can have all the nitrogen you need. Phosphorus, however, really needs to be recovered from our sewerage otherwise it is a mineral on a one-way trip to the bottom of the sea.

It depends on where you are and what your goals are.  Phosphorous certainly needs to be recycled, I didn't mean to suggest that it doesn't.  The Haber-Bosch process requires a Hydrogen source, which is most frequently obtained from knocking hydrogen off of a hydrocarbon like methane.  So if your goal is reduction of carbon dioxide production, relying on synthesized ammoniacal N is counter-productive.  I find it far easier to source P sources than N sources, both on and off the farm, so for me, anything that destroys bio-available N in the name of capturing P is a no-go.  Larger producers, especially those that aren't trying to limit their reliance on synthesized ammoniacal N, will have different goals.

 

ETA:  As far as aquaculture goes, 2:1 feed conversion is attractive.  I don't know anything about silver carp, but if you're in a tropical or sub-tropical climate, Tilapia can approach 1:1 feed conversion, as they filter-feed on algae as well.  One of the alternative ways to start up a tank that I learned from UVI was to use nothing but nitric acid and phosphoric acid as pH down, and potassium hydroxide, potassium bicarbonate, and ammonia as pH up (in appropriate ratios).  This creates an algae bloom that the fingerlings feed on until they are able to readily accept conventional feed.

Edited by JMJones0424
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If you like aquaculture, you'll love this.

 

Fantastic new source of food:
* traditional aquaculture trawls the oceans for by-catch to munch up and feed to captive fish
* this system replaces ocean feedstock with microorganisms grown in nearby tanks
* Or it can be grown in the prawn farm’s own prawn ponds in the 6 month off season
* half the world’s seafood is farmed, so if we eventually replace unsustainble by-catch feedstocks with sustainably grown feedstock pellets, the oceans may get a chance to recover
* it increases marginal prawn farms to profitable prawn farms because the prawns grow 40% larger and are healthier
* increased health gains mean more prawns can be grown in closer proximity
* more prawns in each pond increases production & profits,=
* spin off’s not listed on the show but that I am considering are possible increases in our understanding of micro-plankton or algae growth for feedstocks for other industries.

http://www.abc.net.au/landline/content/2014/s3984247.htm

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