Video of @iidrg discussing what % of your diet you can grow in your backyard with aquaponics:
Has anyone else run any numbers on this?
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This is really great and starts to answer this important question about how much food you can get out of a certain sized system. If many of us begin to keep records of production for different food items from our systems it would help others know what to expect and make informed decisions for scaling or even starting systems.
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The Assoc is also working on messaging docs to reach new growers of different cohorts, including backyard / home growers. This data from Dr Brooks or others can be used for those docs to show folks what is possible for yields under different circumstances
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That sounds great, I agree the data from Dr. Brooks is a good jump start.
Just for some reference markers here, globally there is 2.000m² agricultural land for each living person on this planet. This figure is slowly sinking and I am not sure whether this includes forestry.
This number is referenced in some of the “Weltacker” projects where 2.000m² are cultivated with different regional crops as a demonstration on how the local/regional agricultural space is being used. You might be able to find more detailed information about this figure by following the “Weltacker” pointer.
On the other hand I remember finding some figures on the lower boundary of agricultural space required for a sufficient one person diet. I think the most prominent figure I found back then was 200 m² of high intensive agricultural production space per person. Also here not sure whether that includes forestry for building materials and energy or only food. I suspect it is 200 m² only for food production. Unfortunately I do not have the sources any more.
This was about conventional agricultural and horticultural practices, most likely including industrial grade fertilizer, but not going into the vertical production territory.
Would love to hear your experience on this and maybe some of you do have some reliable sources on this figure.
Regarding Aquaponic production for self sufficiency I think one has to keep in mind that we are doing Horticulture. This is only a small segment of agriculture and you will not be able to feed yourself with Basil, or with lettuce as Dr. Brooks mentions.
The bulk of the nutritional value of our diet comes from grains, tubers and legumes. Tomatos, Cucumbers and lettuce are mainly “water bombs”, thus illustrating 800 pounds of vegetables with a cow is very misleading. The nutritional value of a cow is much different that 800 pounds of vegetables. At the same time, the agricultural space required to produce the nutritional amount of a cow is much bigger than producing the same amount of nutritional value plant based.
I find it also misleading to claim that one could provide 35% of a personal diet with a backyard system for the same reason. This is comparing apples to oranges. The vegtables we produce with aquaponics only have a dry mass between 2% and 5%. The dry mass of grains and such is more than 30%, so when trying to figure out the amount of food one can produce in these kind of systems we at least have to compare dry mass of the food categories.
In addition to that there is a sustainability trap in Aquaponics with regard to fish feed, most of which contains fish meal which is produced from wild catch fish material. Not saying that this is generally and indifferentiatedly negative, there are certain amounts of wild catch byproducts that are smart to use as animal fodder, rather than to discard it.
Still, when assuming one is using a vegetarian fish diet, maybe because one is rearing grass carp, then this feed will be made out of legumes, peas and lentils. If one were to consume these peas and lentils directly, without piping them through the fish, the whole equation would be much more sustainable.
Of course we would not have the lovely tasty fish.
So while I’m all for Aquaponics, I love it, we should be careful, and honest, when estimating productivity and sustainability of this production method.
Thanks Romor I appreciate this analysis. And i think its very important as growers who tout our efficiency for us to have these conversations.
I also think there are a variety of lenses through which to look at this. Some other thoughts:
One other angle is that most people will eat a variety of fresh fruits and veggies even if there are more affordable, more sustainable alternatives like legumes and pulses.
And another angle is someone’s budget. In a sense, aquaponics allows a grower to convert a low cost product - fish food - into a much higher cost product - a tomato or head of lettuce - more efficiently than other means of growing.
And in this scenario, it’s not the growers’ “fault” that our economy doesn’t incorporate the external costs of production (land / water / energy etc ). Such costs - if internalized - could drive people to eating more of the base products that end up as artificially cheap fish food.
But until then, I think for each individual grower analyzing their own budget and dietary demands, Dr. Brooks’ analysis is fair.
(i am also curious about the relative value of the 30% grain / legume dry mass vs the 3% tomato / cucumber dry mass… are there not certain vitamins and minerals in fruits and veggies that are more “valuable” that grains and tubers don’t produce?)
Do others have thoughts?