[TheSoftwareGuy]

Most of the pollution from food production comes from actually producing the food. Things like tractors and stuff use a lot of fuel.

Furthermore, putting farms in urban buildings means that some urban businesses or residences will ha e to be moved further out, increasing pollution. In reality, this would move the pollution to the urban areas, and not reduce it.

Lastly, I can’t think of a reason that you’d know more about farming practices if it happens in an urban environment than in a rural environment

[AngryData]

No, most of the pollution from food production is from fertilizer. Nearly all commercial fertilizer sold is artificially derived from fossil fuels and pollutes just as bad as burning it. Over 60% of the world's total crop yield is the direct result of fossil fuel-derived fertilizer. Removing the fossil-fuel component would make fertilizer production alone rival the current total energy demands of the entire world on that single task.

Tractors are moving tens of thousands of pounds of material at a time and are extremely efficient for the energy they utilize. Tractors may seem like they are using ass tons of fuel from looks alone, people see the huge engine and big cab and chunks of large steel and think it just eats fuel to produce crazy tons of power, but many consumer cars have more horsepower than tractors and frivolously spend fuel on saving mere seconds in both acceleration and braking which are huge wastes. Tractors don't accelerate for long periods of time or waste tons of energy braking all the time just for personal convenience. Tractors are just geared down super low and built ultra-robust with zero concern for physical size. The run better and more efficient than car motors specifically because they didn't have to make any trade offs for compactness, weight, or engine and transmission form. How many cars have turbos and super-chargers? How many of them are tuned for fuel efficiency rather than peak performance? Tractors commonly have them for the sole purpose of fuel efficiency, they never lacked power in the first place because of the lack of other restraints.

[TACIXAT]

The point about displacing people and businesses is only true if real estate is in a fixed quantity. When building is a possibility this is not a zero sum game.

Given the (OP) solution, I was imagining having a broccoli wall in my apartment. This would give me a lot more insight into the farming practices as I would be growing it. Also, near zero transportation externalities.

[tudorw]

Perhaps if the externalized costs of the pollution were more efficiently passed on to the consumer then the benefits of localized urban aquaponics might be enhanced.