As Earth’s population continues to grow, people are putting ever-increasing pressure on air pollution in delhi case study pdf planet’s water resources. In a sense, our oceans, rivers, and other inland waters are being “squeezed” by human activities—not so they take up less room, but so their quality is reduced. 19th century Industrial Revolution, people lived more in harmony with their immediate environment.

As industrialization has spread around the globe, so the problem of pollution has spread with it. When Earth’s population was much smaller, no one believed pollution would ever present a serious problem. It was once popularly believed that the oceans were far too big to pollute. According to the environmental campaign organization WWF: “Pollution from toxic chemicals threatens life on this planet.

Every ocean and every continent, from the tropics to the once-pristine polar regions, is contaminated. Photo: Detergent pollution entering a river. Water pollution can be defined in many ways. Usually, it means one or more substances have built up in water to such an extent that they cause problems for animals or people.

Oceans, lakes, rivers, and other inland waters can naturally clean up a certain amount of pollution by dispersing it harmlessly. If you poured a cup of black ink into a river, the ink would quickly disappear into the river’s much larger volume of clean water. Photo: Pollution means adding substances to the environment that don’t belong there—like the air pollution from this smokestack. Pollution is not always as obvious as this, however. A small quantity of a toxic chemical may have little impact if it is spilled into the ocean from a ship.

But the same amount of the same chemical can have a much bigger impact pumped into a lake or river, where there is less clean water to disperse it. Water pollution almost always means that some damage has been done to an ocean, river, lake, or other water source. Fortunately, Earth is forgiving and damage from water pollution is often reversible. What are the main types of water pollution? When we think of Earth’s water resources, we think of huge oceans, lakes, and rivers. The most obvious type of water pollution affects surface waters. For example, a spill from an oil tanker creates an oil slick that can affect a vast area of the ocean.