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TUNDRA BIOME | What Is A Tundra Biome? | Tundra Region | The Dr Binocs Show | Peekaboo Kidz

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This film explains the difference between biotic and abiotic, terrestrial, freshwater and ocean water ecosystems and the importance weather has on the conditions of many different ecosystems.

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What are ecosystems? Types of Ecosystems for Kids

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Discover what a food chain is and learn how animals and plants get their energy. Find out what the producer is in the food chain in this KS2 guide.

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A large area filled with many trees is called a forest. Forests grow in almost every part of the world. The only places bare of forests are deserts, some prairies and...

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Kids learn about the desert biome. The dryest areas on Earth still have plant and animal life.

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For most of the year, the tundra biome is a cold, frozen landscape. This biome has a short growing season, followed by harsh conditions that the plants and animals in the region need special adaptations to survive.

Tundra form in two distinct cold and dry regions. Arctic tundra are found on high-latitude landmasses, above the Arctic Circle-in Alaska, Canada, Russia, Greenland, Iceland, and Scandinavia, for example-or on far southern regions, like Antarctica. Alpine tundra are located at very high elevations atop mountains, where overnight temperatures fall below freezing.

Tundra regions typically get less than 25 centimeters (10 inches) of precipitation annually, which means these areas are also considered deserts. They have long, cold winters with high winds and average temperatures below freezing for six to ten months of the year. On average, only six to ten weeks of the year have sufficiently warm temperatures and long days for plant growth. The soil in the Arctic is largely permafrost or soil that remains frozen year-round, leaving only a thin surface layer of thawed soil in summer for plant roots to grow in. Tundra soil is also scarce in many of the nutrients that plants need to grow.

These conditions lead to one of the tundra biome's most distinct features: They are largely treeless. (The word "tundra" derives from the Finnish word tunturia, meaning barren or treeless hill.) Instead, the tundra has patchy, low-to-ground vegetation consisting of small shrubs, grasses, mosses, sedges, and lichens, all of which are better adapted to withstand tundra conditions.

Animals in the tundra are also adapted to extreme conditions, and they take advantage of the temporary explosion of plant and insect life in the short growing season. Tundra wildlife includes small mammals-such as Norway lemmings ( Lemmus lemmus), arctic hares ( Lepis arcticus), and arctic ground squirrels ( Spermophilus parryii)-and large mammals, such as caribou ( Rangifer tarandus). These animals build up stores of fat to sustain and insulate them through the winter. They also have thick coats of fur for further insulation. Some save energy by hibernating during the long winter months. Others migrate to warmer climes during winter. Many birds also migrate into the tundra during the growing season to feed, mate, and nest.

Atop the food chain are tundra carnivores, such as arctic foxes ( Vulpes lagopus), arctic wolves ( Canis lupus), snowy owls ( Bubo scandiaca), and polar bears ( Ursus maritimus), which move into the tundra during the summer when prey is plentiful and their usual hunting grounds on sea ice diminish. Many animals, both predator and prey, develop white fur or feathers in the winter months for camouflage in ice and snow.

Tundra insects have also developed adaptations for the cold; mosquitoes ( Aedes nigripes), for example, have a chemical compound that acts as antifreeze, lowering the freezing temperature in their bodily fluids.

Though the tundra is remote, it is increasingly threatened as people encroach on it to build or drill for oil, for example. Perhaps the greatest danger, however, comes from climate change. Warming temperatures could disrupt the cold tundra biome and the life in it, as well as thaw its underlying permafrost, releasing greenhouse gases that would further accelerate global warming.

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Tundras are cold, harsh environments with distinctive biodiversity adapted to these conditions.

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Grasses grow in wide, open spaces around the world. Large areas covered with grasses are called grasslands. Tropical grasslands grow close to the Equator. Temperate…

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Did you know that more wildlife lives around coral reefs than in any other part of the ocean? Find out more about these important ecosystems in our coral reef facts...
What are coral reefs?

When you look at a coral reef, you might think that you are seeing a group of colourful rocks. But don't be mistaken! Reefs are actually made out of living creatures called coral.

Where are coral reefs found?

Coral reefs can be found all over the world! However, most coral reefs grow in shallow, clean ocean waters on either side of the Equator, because they need sunlight and warm temperatures all year to survive.

Some famous coral reefs include the Great Barrier Reef in Australia, the Amazon Reef in Brazil and French Guiana, the Tubbataha Reef in the Philippines and the Miami Terrace Reef in the United States.

Quick facts about coral reefs...

- Coral have growth rings, just like trees!

- The first coral reefs formed on Earth 240 million years ago. That's before the dinosaurs were alive!

- Most coral reefs today are between 5,000 and 10,000 years old.

- There are more than 800 different types of hard coral around the world.

- The Great Barrier Reef is the largest reef system on Earth. You can even see it from space!

Life in coral reefs

Lots of different types of sea creatures call coral reefs their home - giant clams, starfish, sea turtles, , eels, cuttlefish and many, many more. The reefs provide this diverse range of animals with everything they need, including food and shelter.

A lot of animals who live on the reef camouflage themselves to blend amongst the coral, either to stay safe from other animals or to hide as they hunt.

Plants also live on reefs. Algae live inside soft coral, using sunlight to provide food and help the coral grow. In other areas, sea grass provides food for sea animals like dugongs and turtles.

Why are coral reefs endangered?

The biggest threats to coral reefs are spilling into the oceans, damage from ships and boats, and climate change, which makes the water warmer and more acidic.

Save our coral reefs!

To save our coral reefs, many people are working hard to clean up the pollution on land and in the sea. Some countries have even protected their coral reefs.

You can help save coral reefs too, by following some simple tips:

- Conserve your water use, by turning off taps when you brush your teeth!

- If you're lucky enough to go diving, look at the coral - but don't touch it! Touching coral can disturb it, and sometimes kill it.

- Spread the word and tell your friends about how they can help save the planet!

All images: Pixabay

Did you enjoy reading our coral reef facts? Let us know by leaving a comment below!

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Coral reef facts for kids! - National Geographic Kids

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Learn about coral reefs in our coral reef facts for kids. What are coral reefs and where are they found? What lives inside coral reefs?

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Photograph by James L. Amos

Marine ecosystems are aquatic environments with high levels of dissolved salt, such as those found in or near the ocean. Marine ecosystems are defined by their unique biotic (living) and abiotic (nonliving) factors. Biotic factors include plants, animals, and microbes; important abiotic factors include the amount of sunlight in the ecosystem, the amount of oxygen and nutrients dissolved in the water, proximity to land, depth, and temperature.

Sunlight is one of the most important abiotic factors for marine ecosystems. It's so important that scientists classify parts of marine ecosystems-up to three-by the amount of light they receive. The topmost part of a marine ecosystem is the euphotic zone, extending down as far as 200 meters (656 feet) below the surface. At this depth, there is sufficient light for regular photosynthetic activity. Most marine life inhabits this zone. Below the euphotic zone is the dysphotic zone, which can reach from 200 to as deep as 1,000 meters (656 to 3,280 feet) below the surface. At these depths, sunlight is still available, but only enough to facilitate some photosynthesis. Below the dysphotic zone lies the aphotic zone, which does not receive any sunlight.

Types of Marine Ecosystems

Scientists divide marine ecosystems into several broad categories, although there are discrepancies depending on the source about what qualifies as a marine ecosystem. The number of marine ecosystems is actively debated. Although there is some disagreement, several types of marine ecosystems are largely agreed on: estuaries, salt marshes, mangrove forests, coral reefs, the open ocean, and the deep-sea ocean.

An estuary is a coastal zone where oceans meet rivers. Here, nutrients and salts from the ocean mix with those from the river in regions sheltered from extreme weather. As a result, estuaries are among the most productive places on Earth and support many types of life. In addition, because they are located where rivers join the ocean, estuaries have traditionally supported many human communities and activities like fishing, shipping, and transportation.

While estuaries form where ocean meets rivers, salt marshes occur where oceans meet land. These places are rich in nutrients from sediment brought in by the ocean. Marshes are regularly flooded by high tides, making the surrounding ground wet and salty. As a result, the soil is low in oxygen and filled with decomposing matter. These ecosystems are dominated by low-growing shrubs and grasses.

Another coastal ecosystem is the mangrove forest. Mangrove forests are found in tropical areas. These ecosystems frequently flood with ocean water, submerging the roots of mangrove trees. The root systems of mangroves filter out salt and sit above ground to access oxygen. These trees provide a home for a variety of species. Animals, such as fish, crabs, shrimp, reptiles, and amphibians, live among the mangrove's roots while its canopy provides a nesting site for birds.

A bit farther out into the tropical sea are coral reefs, euphotic-zone ecosystems built from the exoskeleton secreted by coral polyps. These exoskeletons form complex structures that shelter many different organisms. Coral reefs are extremely diverse ecosystems that host sponges, crustaceans, mollusks, fish, turtles, sharks, dolphins, and many more creatures. By some counts, coral reefs can account for a quarter of all ocean species.

Beyond the coral reefs lies the open ocean. Open ocean ecosystems vary widely as the depth of the ocean changes. At the surface of the ocean, the euphotic zone, the ecosystem receives plenty of light and oxygen, is fairly warm, and supports many photosynthetic organisms. Many of the organisms that we associate with marine ecosystems, such as whales, dolphins, octopi, and sharks, live in the open ocean.

As the depth of the ocean increases, it gets darker, colder, and with less available oxygen. Organisms living in deep-sea ecosystems within the dysphotic and aphotic zones have unusual adaptations that help them survive in these challenging environments. Some organisms have extremely large mouths that allow them to catch whatever nutrients fall from shallower ocean depths. Others have adapted to get their energy via chemosynthesis of chemicals from hydrothermal vents.

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Marine ecosystems are aquatic environments with high levels of dissolved salt. These include the open ocean, the deep-sea ocean, and coastal marine ecosystems, each of which has different physical and biological characteristics.