This suggestion suggests that specific effects for each biome will show if you are in the biome, if you are surface level or above, if you are 10 meters away from any user-placed blocks (this might be changed later though), and the particles setting in options is set to maximum. These will just be little particle effects like the dust that comes off of redstone and little things that come out when you throw a splash potion.
Forest Biome/Birch Forest Biome/Taiga Biome
You will sometimes see little leaves that float around. They won't be everywhere just a little bit.
Little particles of sand will be blowing around the desert. They look like the pixels on sand. You see it almost everywhere you go in the desert biome.
Cold Taiga Biome/Tundra Biome
Little sparkles would be rising from the ground from the sun reflecting off the snow. You see them once in a while.
Swamp Biome/River credit to BananaGummyBear64 for suggesting it to be added to rivers
There would be bugs flying around the swamp. It is common to see them. At night, the are yellow and bright.
Would be mix of the particles in the forest biome and the particles in the swamp biome.
Floating in the air would be exp orb looking things except with a darker shade (changed as many people don't care for the previous idea).
Roofed Forest Biome
A mix of the forest biome and mushroom biome particles.
As same as the desert biome particles but the colored red instead.
Sunflower Plains Biome
Yellow petals would be floating around in the wind occasionally.
Nether credit to Droideka30
Orange-red particles would slowly rise from the ground around the nether. Would be very common.
Black particles would be floating around at a slow pace. Would be a common sight to see.
I know the descriptions of the particles are short but there isn't much to say about them.
All the particles would only appear from sea level and higher. As a reminder, these aren't items in the game, just little particle effects that could make the game more unique and colorful.
EDIT: Updated the suggestion for the snapshots.
Hey look, this suggestion hasn't gotten one no support. That's an achievement, I guess.
Particles off: no particles at all
Particles minimum: limited particles and no biome effects
Particles fair: the current maximum particles we have now but no biome effects
Particles maximum: the current maximum particles we have now but with biome effects