 Ecosystems establish in and around hydrothermal vents as the abundance of inorganic substances, namely hydrogen, are constantly being supplied via magma in pockets below the sea floor.Other lithotrophs are able to directly utilize inorganic substances, e.g., iron, hydrogen sulfide, elemental sulfur, or thiosulfate, for some or all of their electron needs.Here are a few examples of chemolithotrophic pathways, any of which "may" use oxygen, sulfur or other molecules as electron acceptors