Complex sentence: Note that, for the purposes of this article, man made structures such as the Panama Canal are not taken into avention is not universally agreed upon, and presents particular difficulties in the case of mountaintop removal.
Split into simpler sentences: Note that, for the purposes of this article, man made structures such as the Panama Canal are not taken into account. This convention is not universally agreed upon, and presents particular difficulties in the case of mountaintop removal.