eco-fear near-future dystopia / cataclysm movies I'd never heard of, via this fascinating post at We Are Mutants by Michael Grasso:
"At the beginning of the 1970s, a sense that techno-industrial man’s ongoing destruction of the environment would ultimately lead to global doom was widespread in the West.... For audiences in our own “far-future” year of 2020, these ’70s anxieties probably live on most memorably in pieces of pop culture and entertainment. Films such as Soylent Green (1973), based on the 1966 Harry Harrison novel Make Room! Make Room!, depicted a suffocating, overpopulated future where humans resort to a pair of extreme social taboos—mass euthanasia of the elderly and concomitant cannibalism—to simultaneously alleviate both the population and resource crises. Two lesser-known population crisis sci-fi films—No Blade of Grass from 1970 and Z.P.G. (Zero Population Growth) from 1972 (both available as part of the Criterion Channel’s “Seventies Sci-Fi” series during the month of January)—provide a fuller context for the countervailing hopes and fears of a Cold War-era society unsure of its formerly gleaming technological future: would we descend into brutality and barbarism as soon as the worldwide system collapsed? Or would our future require ever more intricate and intimate technocratic control over every aspect of our lives to ameliorate the very conditions that were created by technocratic control?"
"... Paul and Anne (not credited) Erlich’s The Population Bomb exploded onto the scene in 1968, but the book was preceded by dozens upon dozens of postwar science fiction stories and novels that predicted an overpopulated, underfed future. The film No Blade of Grass was itself based on one of these, John Christopher‘s 1956 “cosy catastrophe” novel The Death of Grass, which used elements of the nascent Green Revolution as inspiration for its tipping-point event: a disease that begins wiping out grain species in Asia before migrating to the West...
"No Blade of Grass is hands down the most unrelentingly grim film it has ever been my displeasure to view. It is a nasty little piece of exploitation cinema mixed with weak and muddled agitprop, and it offers the viewer zero opportunity for ironic detachment or campy enjoyment to distract from its gleeful depiction of human brutality and horror. No Blade of Grass takes the old saw of “any society is nine meals from anarchy” to its extreme conclusion: postwar Britain turns from a cozy land full of brave ex-military men, sober scientists, and doughty gentleman farmers into a wild landscape of opportunistic murder, brutal rape, and the abandonment of those perceived to be weak and useless, virtually overnight...."
"the equally grim but essentially satirical far future of Z.P.G. practically felt like an amusement park ride. In Z.P.G.‘s future, the Earth is cloaked in “smog”: pollution has been left unchecked and has killed virtually all plant and animal life on Earth… aside from humans. Overpopulation is the clear culprit of these conditions, and in the opening moments of the film, the “President of the Society” (one of the only characters in the film who wears a 20th-century-style suit; his physical and vocal resemblance to a cross between Peter Sellers’s President Merkin Muffley and real-world Cold War eminence grise Henry Kissinger seems completely intentional) announces that the World Federation Council has decided that all human childbirth must be utterly eliminated for the next 30 years....
"Every home bathroom cubicle is equipped with an abortion device; informers who identify breeders are given additional ration cards; corporations market uncanny robot children to the baby-hungry populace...."