The original Green Revolution consisted of various agricultural technologies that have largely made starvation a thing of the past. Hybrid grains and rice, various chemical fertilizers, and pest control have all played a part. More recently of course, “green” has a different, less benign meaning.
Recently resigned prime minister Rajapaksa of Sri Lanka was convinced by environmentalists to ban synthetic fertilizers after which agricultural outputs in that pastoral island dropped by substantial amounts. Power Line provides this longish quote from the Times (U.K., behind paywall):
[T]hat strategy backfired in spectacular fashion. Domestic rice production fell by 14 per cent from 2021 to 2022, forcing the nation, long self-sufficient in rice production, to import hundreds of millions of dollars of rice and more than eroding all of the savings from ceasing fertiliser imports. On top of that, the ban decimated tea production, leading to a $425 million economic loss to the industry in its first six months of implementation. Tea, one of the nation’s primary crops, is a key source of its total export income, making a bad foreign exchange situation far worse.
The government ignored its own agricultural experts, instead convening representatives of the nation’s small organic sector to guide the nation’s agricultural policies. The result turned a bad situation into a disaster.
Completely man-made, that disaster was the result of bad policy undertaken with the best of intentions. Learn the lessons: go woke, go broke; go green, go hungry.