What color effect is applied on ?

I think they are a combination of effects, and it looks like they are slightly different between the two photos.

Just by a quick visual comparison, I think the subject was treated separately from the background. It looks like his face is the same, but he becomes slightly desaturated toward the bottom of the image. The background looks consistently desaturated. Then a graphic was placed over another gradient that goes from transparent to black.

The second one is similar but it looks like the image was first color corrected so that it was less green and more red. Then the same treatment was applied.

One way to create these effects, would be to do the following:

1. Use the Object Selection Tool to select the subject (either draw around the subject or click Select Subject from the Options bar or Contextual Task Bar)
2. Apply a Hue/Saturation adjustment layer while the selection is active to automatically create a layer mask from that selection
3. Decrease the saturation in the adjustment layer, duplicate the Hue/Saturation adjustment layer (including the layer mask)
4. Add a gradient from white to black on the white portion of the layer mask (to fade out a desaturation effect on the subject as in the first pic)
5. Invert the layer mask on the duplicated adjustment layer
6. Add a gradient adjustment layer where both color stops are black where one has 100% opacity and the other 0% and adjust the gradient so that it's at the bottom of the image.
7. Add the graphic.

For the second image, you could start by adding either a Levels or Curves adjustment layer to adjust the green/red or convert the image to a Smart Object and apply the Camera Raw filter to adjust the colors.