Imagine a glass of your favorite drink that never became empty. Now think about what really happens. You take a drink and there is less in the glass. You keep drinking and soon it is all gone. Good thing you have more to refill your glass. What if there would never be any more of your favorite drink. What would you do? Now you know the difference between renewable and non-renewable. Its too bad that many things here on Earth will run out. This includes some of our natural resources we depend on. Things like oil will not last forever. There is a limited supply. Someday, we will run out, so then what? At current rates of use, coal will last about 300 years. Petroleum will be used up in just a few decades.

What will happen to oil and why?

When land is cleared, habitats are lost. It may be cleared for agriculture. It may also be used for building new homes or businesses. Within the past 100 years, the amount of land used for agriculture has almost doubled. Land used for grazing cattle has more than doubled. Many wetlands have also been lost to agriculture. The U.S. has lost almost all the natural tall-grass prairies. Thee areas of tall thick grass have virtually disappeared. These areas of land had thick fertile soil. Their grasses had very deep root systems. These deep and thick roots reduced the amount of soil erosion. They also were home to many plants and animals. Prairies were wonderful places. They were home to colorful flowers, prairie dogs, and herds of bison.

How can habitats be lost?

Milwaukee, Wisconsin (CNN) -- President Barack Obama, in a bid to create jobs and boost economic growth, called on Congress on Monday to pass a $50 billion plan to renew the country's transportation infrastructure. His address was the first of two speeches the president is scheduled to make this week to frame his administration's ongoing response to the recession, less than two months ahead of midterm elections in which Democratic majorities in the House and Senate are in jeopardy. "Today, I am announcing a new plan for rebuilding and modernizing America's roads, and rails and runways for the long term," said Obama, who spoke on Labor Day in Milwaukee, Wisconsin -- a state with competitive gubernatorial and U.S. Senate races. "We used to have the best infrastructure in the world. We can have it again," he said to loud cheers from a crowd of union workers. The proposal envisions -- over a six year period -- rebuilding 150,000 miles of roads, 4,000 miles of rail and 150 miles of airport runways. It also would include modernizing the nation's air traffic control system in an effort to reduce delays and travel time. "This will not only create jobs immediately. It's also going to make our economy hum over the long haul," said the president. Obama hopes to work with Congress to enact an up-front investment of $50 billion -- an amount a White House statement said would represent a significant chunk of new spending on infrastructure. The investment would then be paired with what the administration called a framework to improve transportation spending. The long-term plan would include the establishment of an Infrastructure Bank, which would leverage federal dollars and focus on projects that could deliver the the biggest bang for the buck, Obama said. The president stressed the need for Democrats and Republicans to work together on the transportation initiative, which would need to be approved by Congress.
What did the president say would be two significant benefits of spending to rebuild many miles of roads, railways, and runways?