A pointer from Roger Ebert's review of Saturn 3. In two sittings as it's a bit boring. A far less animated Bruce Dern (than he was in the contemporaneous The King of Marvin Gardens) plays the last sane man (a not-too-bright greenie) in a world gone mad, which is all the proof you ever needed that we're screwed and have been for a long time. Again we're somewhere out near Saturn on a Discovery-like ship with forests under domes — the last remaining biotics since the Earth was laid waste. After getting unenlighteningly het up, he rejects the command to nuke the forests (for commercial not taxation reasons) by getting rid of his pesky colleagues, making do with his bestie robots (robos over bros!) in what is a dry run for Star Wars (etc). At some point it is suggested he commit suicide and (spoiler) eventually he does.
There might be something here if you're into the aesthetics (geodesic domes!) or the degenerate form of post-humanism on offer: the final scrap of nature is entrusted to a sort-of inverted HAL9000, making for a kind of droid/drone starbaby. There are a few Joan Baez tunes which I didn't enjoy too much.
Roger Ebert: four stars! "Deep space effects every bit the equal of those in 2001" — I missed those. The title is clearly a riff on Silent Spring. There are no ladies in this picture.