Blender is fun, but has some really annoying warts. The lack of infinite planes means you must add atmospheric haze with the World:Mist option. After much experimentation, I found that setting the mist color to match the horizon color of the skymap (you are using a skymap, aren’t you?) and a quadratic falloff with Start 0, Distance 1000 and Height 100 works well. Make sure you set Mist Intensity (Misi) to 0; contrary to intuition it sets the intensity of the mist at the camera rather than scaling the mist effect as a whole.
Particle systems are fun, but static particle systems for e.g. grass do not obey deflection properties. They do obey fields and vortices. It’s very special.