Post #4496444

2026-08-11 10:20 UTC

Figure 1 from Duffy et al. 2021. Line chart for photosynthesis and ecosystem respiration in C3 and C4 plants on a temperature scale. C3 plants = all plants, including crops and trees. C4 plants = grasses and sweet corn C3 plant photosynthesis is highest at 16°C then drops and encounters the respiration line at 24°C, meaning, from here on, respiration is higher than photosynthesis and the ecosystem becomes a net CO2 emitter. The photosynthesis line drops below zero at 26°C. C4 plants (mostly grasses) have their highest photosynthesis at 27°C, then drop and meet the respiration line at 30°C – from here on, the ecosystem is a net CO2 emitter. The line drops below zero at 34°C. Source: Duffy et al 2021. https://www.science.org/doi/full/10.1126/sciadv.aay1052 I only added the labels because colour-blindness has problems to distinguish green=C3 and brown=respiration.

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@anlomedad@fedifreu.de 2026-08-11 10:37

I believe, UK's northern latitudes can't simply replace home-grown meat with home-grown veggies. One limiting factor could be the shorter growth season. Or maybe also because the soil isn't suitable for much else other than grass. It's why I think the question re -61% versus more imported CO2 is important. And one addition: he didn't mention drainage at all. But the UK is just as bad as Germany regarding draining of the land, if not worse. Keeping water in the landscape is so important. A patch of forest or hedges between fields cool the immediate surrounding because they can evaporate water. Through little natural subsurface channels, water from such green islands also becomes available for adjacent field crops. And if the island is connected to an aquifer… 😍 so I think, it's really important to break up the monoculture and add patches of wild nature. And plug the drainage pipes as much as possible.

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