Natural Capital
Natural capital can be seen as the total value of the environment to sustain life, though living systems—wetlands, savannas, forests, tundra, estuaries oceans and ponds, as well as its inhabitants. For example, a forest provides not only the resource of wood, but also the services of water storage and flood management. The Worldwide Fund for Nature's inventory of natural capital, the Living Planet Index (LPI) fell by over 30% from 1970 to 1995.