All About Water

Rainforests are some of the most incredible ecosystems on Earth. They contain unique structures which allow for massive amounts of growth in both plant and animal life. Many plants and animals on Earth can only live in the rainforest. Even though many of these plants give oxygen to the world and offer potential cures for cancer, the rainforests are being destroyed at an alarming rate.

Features of the Rainforest

While there are many rainforests in different areas of the world, all rainforests have certain features in common. To be classified as a rainforest, an area must have a large amount of rainfall per year. Most rainforests experience between 68 to 78 inches of rainfall annually. Usually a rainforest is divided into four layers. The emergent layer is the top layer, followed by the canopy, the understory, and the forest floor, which receives about 2% of the rainforest’s sunlight.

Plants and Animals of the Rainforest

The rainforest is a lush and fertile environment, so fertile in fact that there are still many types of plants and animals that remain undiscovered by humans. No one knows exactly how many species of plants and animals are in the rainforest, but estimates indicate that 40-75% of all life on Earth can be found somewhere in the rainforest. Most plant and animal life is found in the canopy layer due to the rich and moist conditions and ample sunlight. Since the understory and forest floor layers receive so little sunlight, only low light plants can grow in these layers. The emergent layer is usually too hot to sustain much life.

Even though the rainforest is very fertile, the soil is not. Most plants that grow at the lower level only have their roots in the top layer of soil, as the lower levels are filled with mineral deposits and rapid bacterial decay. Plants on the lower layers tend to rely on the decomposing plant and animal life on the top layers of soil for nutrients.

The Importance of the Rainforest

Even though the rainforest only covers about 6% of the planet, it plays many crucial roles not only to the survival of humans, but also to the survival of all life on Earth.

Rainforests contain numerous plants in condensed areas, allowing for the production of massive amounts of the world’s oxygen.  In fact, the Amazon rainforest alone  is responsible for about 20% of the oxygen created on Earth. Rainforests also take in a huge amount of carbon dioxide each year. Both processes are crucial to life on Earth.

The rainforest also holds many different medicines that can only be found in the rainforest. Somewhere around 70% of the 3000 plants that are effective against cancer are found in tropical rainforests around the world.

Even with all of these benefits, the rainforest is still being destroyed. Estimates indicate that about one and a half acres of tropical rainforest is being destroyed for its wood each second. Oil spills, toxic byproducts, and other man-made contaminates are also poisoning the waters of the rainforest, killing many plants and animals. While rainforests cover only 6% of our Earth now, they used to cover 14%. Scientists predict that we could see the end of the tropical rainforest within 40 years. This would be an unspeakable blow to the plants, animals and well-being of Earth.

For more information on water and biomes, check out Role of Water in Ecosystems and Biomes

• Extreme cold
• Simple structure of vegetation
• Short growth and reproduction seasons
• Dead organic materials provide most of the energy and nutrients in the system
• Large oscillations in the population

Climate of the Tundra

The growing season lasts for a meager 50 to 60 days in Arctic tundra, and about 180 days for Alpine tundra. The average temperature in winter is -30 degrees Fahrenheit. In the brief summer, the temperature averages 37 to 54 degrees. A layer of permafrost, or permanently frozen soil, is always present, although it’s depth is variable. Bogs and ponds form in the Arctic tundra in the summer when the permafrost melts slightly and precipitation floods the area. These bogs provide moisture for the plant life that is acclimated to the environment. Alpine tundra soil has better drainage.

Plant Life in the Tundra

The plant life that exists is simple, but of surprising diversity. The tundra is able to support:

• Reindeer moss
• Low shrubs
• Sedges and grasses
• Lichen
• About 400 different types of flowering plants

In addition to these plants, Alpine tundra supports:

• Tussock grasses
• Dwarf pines
• Heaths

The plants found in the tundra are short and grow close to the ground. They are adapted to the harsh cold.

Animal Life in the Tundra

Like plant life, the animal life is also diverse. Herbivorous mammals like voles, caribou and arctic squirrels call the Arctic tundra their home, as do the carnivorous mammals that feed on them such as arctic foxes and polar bears. Migratory birds like ravens, falcons and terns can survive here. The cold waters are filled with fish like cod, salmon and trout. Alpine tundra supports pikas, mountain goats and elk, grouse-like birds, and insects such as beetles, grasshoppers and butterflies.

Water Pollution in the Tundra

Because the arctic and alpine ecosystems are so fragile, anything the pollutes the water that the system depends on creates a grave threat to the entire system. A growing concern in the arctic tundra is the threat of oil spills, which float in the water and suffocate plant and animal life. Acid rain is an ongoing concern in the Alpine tundra ecosystem. Many mountain lakes are being rendered sterile, as they do not have much of a buffering capacity.

For more information on water and biomes, check out Role of Water in Ecosystems and Biomes