I was curious about a few things about pollution. How close to the spawn does it have to be? I see that it is nearly touching the base, does the cloud of pollution have to touch the spawner, as I have not yet been attacked and the cloud must be over some of the biters around the spawner.

I was looking at the F7 mode with the map on, and the white numbers are elevated to like 26 right over the spawner. Does the actual effect of pollution occur only where the cloud is shown on the map? I would think that it might extend a bit beyond that.

Can someone tell me what the red, green and blue numbers mean? I see the white are the amount of pollution. And what are those green circles for? I thought they meant trees absorbing the pollution, but they move around too.
I think understanding that would go a long way to predicting attacks, I am kind of confused since the pollution is right on top of them, and they have not yet attacked. Also I thought the effect might spread further than the map indicates, as many of the spawners are quite far away.
Also, can anyone dare to explain what the F7 shows on the ground? All those red and blue boxes and numbers, I thought a lot about what they can be and cant seem to find a suitable explanation:

Thank you for any assistance!