A recent study suggests that food grown in cities produces more CO2 than conventional farming. Is this really true? Is carbon the whole story? What would it ...
Sorry for the clickbait title but I thought a great video from a great but not well known channel.
I read the paper before seeing this video post. Maybe not what you’re looking for but here’s my TLDR takeaways from the publication:
Infrastructure is the largest driver of carbon emissions at low-tech Urban Agriculture (UA) sites (63% of impacts)
A raised bed built and used for five years will have approximately four times the environmental impact per serving as a raised bed used for 20 years. The issue is, with frequent moving and development in urban environments, much of the infrastructure is gone or redone in a short timespan.
Climate-friendly sites in the sample cut their emissions by more than 52% by upcycling refuse from the urban environment for raised beds, structures and other infrastructure—twice as much savings as high-carbon sites
Composing
Sites in the sample used 95% less synthetic nutrients than conventional farms
poorly managed composting can exacerbate GHGs. The carbon footprint of compost grows tenfold when methane-generating anaerobic conditions persist in compost piles.
We estimate that careful compost management could cut GHGs by 39.4% on sites that use small-scale composting.
rainwater
In this study, more than 50 (of ~75) sites practiced rainwater recovery, but only four derived most of their irrigation this way
sites primarily used potable municipal water sources or groundwater wells, consistent with the underutilization of rainwater seen across past research
Irrigation from these sources emits GHGs from pumping, water treatment and distribution, and this rose to as high as 83% of total emissions on one UA site
Non caloric benefits
UA practitioners overwhelmingly reported improved mental health, diets and social networks
Cost–benefit analysis of a collective garden in the UK estimated that social benefits, such as improved well-being and reduced hospital admissions, accounted for 99.4% of total economic value generated on-site
Because emissions allocation often follows economic value generation46, growing spaces that maximize social benefits can outcompete conventional agriculture when UA benefits are considered holistically.
Although UA may increase the carbon intensity of fruits and vegetables, these foods account for a small share of total dietary carbon impacts, which are driven mainly by meat and dairy. Studies have shown that UA practitioners often reduce their intake of animal products49. Future work should quantify this tradeoff between elevated carbon footprint in urban produce and shifting diets.
Is there an article version for the argument?
Not that I know of. He’s summarizing and critiquing some research that was done recently. Here’s an article about the research but the video does raise some caveats so take it with a grain of salt: https://theconversation.com/urban-agriculture-isnt-as-climate-friendly-as-it-seems-but-these-best-practices-can-transform-gardens-and-city-farms-221537
I read the paper before seeing this video post. Maybe not what you’re looking for but here’s my TLDR takeaways from the publication: