Petroleum now let's see...Petroleum also used for cars and other vehicles is distributed around the world for different uses. Today, fossils fuels are necessary for human survival and everyday life and are the primary source for the world’s energy. They are used for heating, transportation, generating electricity, and creating common products like computers, cosmetics, paint, and household appliances.
“Years ago, when prehistoric animals and plants died, layers of rock and dirt gradually buried them. Over millions of years, heat and pressure from Earth's crust decomposed these organisms into one of the three main kinds of fuel: oil (also called petroleum), natural gas, or coal.”
The exchange of a river's flow and sediment conveyor downstream of a dam often causes the greatest sustained environmental impacts. Yet even complex changes in the number and timing of water flows impact aquatic and riparian life, which can explain the biological web of a river system.