That the Chernobyl exclusion zone has become an animal sanctuary is held out as an example of ability of ecosystems to tolerate low-level radioactivity. After the humans moved out, the animals flourished.
But I have another theory. Maybe the ecosystem isn't doing all that well. It just appears so in comparison with conditions when human activity dominated. Compared to an uncontaminated, undisturbed ecosystem, it's just doing so-so. The theory being that the presence of human activity is worse for ecosystems than low-level radiation. James Lovelock argued that we could save the rain forests from the ravages of man by burying nuclear waste in them. [1] That implicitly suggests that a little radiation is better for wildlife than human presence, at least according to Lovelock.
But I have another theory. Maybe the ecosystem isn't doing all that well. It just appears so in comparison with conditions when human activity dominated. Compared to an uncontaminated, undisturbed ecosystem, it's just doing so-so. The theory being that the presence of human activity is worse for ecosystems than low-level radiation. James Lovelock argued that we could save the rain forests from the ravages of man by burying nuclear waste in them. [1] That implicitly suggests that a little radiation is better for wildlife than human presence, at least according to Lovelock.
1 https://www.wired.com/2011/04/ff-chernobyl/