Cav,
you're right. I didn't notice. this is turning into a much more difficult to answer question!
I have devised a context for the sentence:
The Honduras rainforest has long been a haven to many diverse classes of organisms, but recently a factor has grown which threatens its very existence: <statement>.
the following 4 alternatives work then in this context:
1 - "this is the artificial taxing of the land by human influence."
2 - "this is the artificial imposition of human will on the land."
3 - "this is the artificial human tax on the land"
4 - "this is the artificial tax which humans have imposed on the land"
in all of them, i would recommend artificial be removed for it's redundancy, except for in case 4.
are you following, navigator?