Hydroelectric energy is power made by moving water. To irrigate is to water crops by bringing in water from pipes, canals, sprinklers, or other man-made means, rather than relying on rainfall alone. Pollution is the introduction of harmful materials into the environment. These harmful materials are called pollutants. Precipitation is any type of water that forms in the Earth's atmosphere and then drops onto the surface of the Earth. Water vapor, droplets of water suspended in the air, builds up in the Earth's atmosphere before precipitating.
Rain is liquid precipitation: water falling from the sky. Raindrops fall to Earth when clouds become saturated, or filled, with water droplets. A river is a large, natural stream of flowing water. Rivers are found on every continent and on nearly every kind of land. A stream is any body of flowing fluid. The most familiar type of stream is made of water, although streams can also be made of air, lava, electricity, or any other fluid.
The water cycle describes how water is exchanged cycled through Earth's land, ocean, and atmosphere. A watershed is an entire river system—an area drained by a river and its tributaries. It is sometimes called a drainage basin. Droughts can cause a variety of problems to local communities, including damage to ecosystems, crops, and a shortage of drinking water.
From "Cowtown" to a natural gas boom amid a water shortage: sustainability can happen in unexpected places. Freshwater is a precious resource worldwide.
In the small Japanese village of Harie, residents use a unique method to keep their fresh water clean and clear. Watch this video to discover this rather fishy system. Made of white granite, it was designed by Benjamin Wright who was considered the father of American civil engineering.
The Bonneville Dam, on the Columbia River, has provided electricity to millions of residents of Washington and Oregon since The Role of Water in the Generation of Electricity Students discuss what freshwater is and use maps to predict and identify places around the world where it is scarce. Using Fresh Water Students explore maps to discover the distribution of fresh water resources on Earth, and they examine graphs to discover how fresh water supplies are used by humans.
Using Groundwater Wisely Students use interactive computational models to explore the relationship between infiltration and recharge in natural and urbanized areas. Groundwater and Surface Water Students use interactive computational models to explore the underground flow of water and how it affects surface bodies of water.
Groundwater Movement Students explore how porosity and permeability of different sediments affect the way water flows through Earth's layers. Waterworks Around the World Students investigate how the geography of an area influences and determines waterworks projects. Mapping U. Watersheds Students trace the Mississippi River and its major tributaries on a map of the United States. Hydroelectric and Geothermal: Benefits and Drawbacks Students analyze the benefits and drawbacks of hydroelectric and geothermal energy and the environmental impacts on a specific geographic location.
Our Hydrosphere Students investigate the interconnectedness of Earth's water reservoirs by learning about the hydrosphere. Making Informed Environmental Decisions Students use a decision-making process to explore the complex nature of real-world environmental conflicts and how they get resolved.
National Geographic Explorers Introduce students to explorers passionate about freshwater issues. Just ask your neighbor, a tomato plant, a trout, or that pesky mosquito. Surface water includes the lakes, reservoirs human-made lakes , ponds, streams of all sizes, from large rivers to small creeks , canals human-made lakes and streams , and freshwater wetlands. The definition of freshwater is water containing less than 1, milligrams per liter of dissolved solids, most often salt.
As a part of the water cycle, Earth's surface-water bodies are generally thought of as renewable resources, although they are very dependent on other parts of the water cycle. The amount of water in rivers and lakes is always changing due to inflows and outflows.
Inflows to these water bodies will be from precipitation , overland runoff , groundwater seepage, and tributary inflows. Outflows from lakes and rivers include evaporation , movement of water into groundwater, and withdrawals by people. Humans get into the act also, as people make great use of surface water for their needs.
So, the amount and location of surface water changes over time and space, whether naturally or with human help. Certainly during the last ice age when glaciers and snowpacks covered much more land surface than today, life on Earth had to adapt to different hydrologic conditions than those which took place both before and after.
And the layout of the landscape certainly was different before and after the last ice age, which influenced the topographical layout of many surface-water bodies today.
Glaciers are what made the Great Lakes not only "great, " but also such a huge storehouse of freshwater. Nile Valley in Egypt—Water makes the desert bloom. If you ever wondered if the expression "Water makes the desert bloom" was true, there is no better proof than this satellite picture of the Nile Valley in Egypt.
Credit: NASA. As this picture of the Nile Delta in Egypt shows, life can even bloom in the desert if there is a supply of surface water or groundwater available. Water on the land surface really does sustain life, and this is as true today as it was millions of years ago.
I'm sure dinosaurs held their meetings at the local watering hole million years ago, just as antelopes in Africa do today. And, since groundwater is supplied by the downward percolation of surface water, even aquifers are happy for water on the Earth's surface. You might think that fish living in the saline oceans aren't affected by freshwater, but, without freshwater to replenish the oceans they would eventually evaporate and become too saline for even the fish to survive.
As we said, everybody and every living thing congregates and lives where they can gain access to water, especially freshwater. Just ask the 6 billion people living on Earth! Here's a satellite picture of the world at night. The most obvious thing you can see is that people live near the coasts, which, of course, is where water, albeit saline, is located. But the interesting thing in this picture are the lights following the Nile River and Nile Delta in Egypt the circled area.
In this dry part of the world, surface-water supplies are essential for human communities. And if you check the price of lakefront property in your part of the world, it probably sells for much more than other land.
View the full image from NASA. To many people, streams and lakes are the most visible part of the water cycle. Not only do they supply the human population, animals, and plants with the freshwater they need to survive, but they are great places for people to have fun.
You might be surprised at how little of Earth's water supply is stored as freshwater on the land surface, as shown in the diagram and table below.
Freshwater represents only about three percent of all water on Earth and freshwater lakes and swamps account for a mere 0.
Twenty percent of all fresh surface water is in one lake, Lake Baikal in Asia. Another twenty percent about 5, cubic miles about 23, cubic kilometers is stored in the Great Lakes. Rivers hold only about 0. You can see that life on Earth survives on what is essentially only a "drop in the bucket" of Earth's total water supply! People have built systems, such as large reservoirs and small water towers like this one in South Carolina, created to blend in with the peach trees surrounding it to store water for when they need it.
These systems allow people to live in places where nature doesn't always supply enough water or where water is not available at the time of year it is needed.
The Earth is a watery place. There are many environmental factors that arise due to the usage of water in one way or another and for every action that man does, there is a resultant effect on the ecosystem.
In this tutorial, some scenarios where human action results in a response from the ecosystem, either physically or chemically, are described. This tutorial introduces flowing water communities, which bring new and dithering factors into the equation for possible species occupying the area. Read to know more Skip to content Main Navigation Search. Dictionary Articles Tutorials Biology Forum. Freshwater Ecology Freshwater ecology focuses on the relations of aquatic organisms to their freshwater habitats.
Freshwater Producers and Consumers Freshwater ecosystem is comprised of four major constituents, namely elements and compounds, plants, consumers, and decomposers. Pollution in Freshwater Ecosystems There are many environmental factors that arise due to the usage of water in one way or another and for every action that man does, there is a resultant effect on the ecosystem.
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