Is there any karma incurred by the Earth as a planetary being, alone?✶
What makes humanity (not including the godbeings) the primary specie on the planet, and not just another animal specie, is the ability to make "mistakes". (This is one of humanity's distinctions that elevates them above the animal species.) The Earth doesn't have karma, as a planetary body, because the Earth doesn't make mistakes.
The other species that exist on Earth along with humanity, are expressing the Infinite's intent for their respective specie, without opposition and having no individual choices. They are pure vessels for the Infinite's intent to articulate through.
✶See: What is Planetary Karma?