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The World Biomes
The world seems no less a magical place than the world of fairy tales. If you don't believe me then think about the seasons, and the different climates that different regions in the world boast of at the same time, and how animals and plants living there have adapted different features to survive.
Basically, all animals and plants require specific climate and food, and the place where they find these is called their habitat or biome. Here we will have a look at the various habitats that can be found on the face of the Earth.
As its name suggests these are regions which receive a lot of rainfall throughout the year. This biome is further divided into two types - Tropical and Temperate. In both tropical and temperate forests vegetation is dense, trees are tall and rich in colour and both have numerous species of plants and animals. Mosses and ferns are found here in abundance, too, especially in temperate rainforests.
Though both are lush and wet, Tropical rainforests have a downpour of 400 inches of rain per year, whereas in Temperate rainforest it rains about 100 inches per year. Tropical rainforest are warm and moist whereas Temperate rainforests are cool. There are abundant species of animals found here including, tigers, chimpanzees, monkeys, snakes, bats, lions and foxes.
The defining characteristic of a desert is that it is dry. Depending on its geographical location the rainfall varies from half an inch to 15 inches. Hot and Dry Deserts usually have very little rainfall and/or concentrated rainfall in short periods between long rainless periods. This averages out to fewer than 15 cm a year. Cold Deserts usually have lots of snow. They also have rain around spring.
Hot and Dry Deserts are warm throughout the fall and spring seasons and very hot during the summer, the winters usually have very little, if any, rainfall. Cold Deserts have quite a bit of snow during winter. The summer and the beginning of the spring are barely warm enough for a few lichens, grasses and mosses to grow. Many of the fascinating features of desert plants are adaptations - traits that help the plant survive in its harsh environment. Desert plants have to undergo two main adaptations: ability to collect and store water and features that reduce water loss.
Desert plants often look different than plants in any other biome like cactuscreosote bush, soaptree yucca, etc. Hot and Dry Desert animals include small nocturnal (only active at night) carnivores. There are also insects, arachnids, reptiles, and birds. Some examples of these animals are borrowers, mourning wheatears, and Horned Vipers. Cold Deserts have animals like antelope, ground squirrels, jack rabbits, and kangaroo rats.
The Temperate Deciduous Forest
The Temperate Deci-duous Forest biome has four seasons of winter, spring, summer, and fall. Animals and plants have special adaptations to cope with these yearly changes. One of the most interesting features of the temperate deciduous forest is its changing seasons. The word "deciduous" means exactly what the leaves on these trees do: change colour in autumn, fall off in the winter, and grow back again in the spring. This adaptation helps trees in the forest to survive winter.
Before winter, deciduous trees and plants become dormant. They lose their leaves and seal the places where these leaves were attached with a protective covering called a leaf scar. If they kept their leaves, the water in the leaves would freeze into ice, damaging the leaves and leaving the plant vulnerable to bacteria or fungi. Here you will find trees such as the American beech, common lime, guelder rose, lady fern, pecan and white oak. The, black bear, Eastern chipmunk, European red squirrel and white-tailed deer are some of the animals that can be found here.
Grassland is a grassy, windy, partly-dry biome. It covers almost one fourth of Earth's surface. It often separates forests from deserts. However, most of the area is covered with deep-rooted grasses, and only one per cent of it is occupied by trees and shrubs. Names such as savanna, pampas, campos, plains, steppe, prairies and veldts are used for this area.
In the summer these area receive a lot of rain. African savannas boast of large grazing areas for herds of animals. African Elephant, African Wild Dog, Black Mamba, Chacma Baboon Grant's Zebra, Koala Bear and Lion are animals that inhabit the area.
Plants though not many can be found in this area, some of these are Acacia Senegal, Baobab, Bermuda Grass, Candelabra Tree, Elephant Grass, Gum Tree Eucalyptus, Kangaroo Paw.
It exists in various forms such as lakes, rivers, ponds, swamps, or wetlands, and is host to a wide variety of plants and animals.
Lakes and ponds are like the oceans. They are divided into separate zones which are defined by their distance from the shore. The area, which is closest to the shore, has a wide variety of species due to its warm, shallow environment. Various species of invertebrates, crustaceans, plants and amphibians thrive in this environment, and in turn provide food for predators such as birds, reptiles and other creatures inhabiting the shoreline.
The open water near the surface of a lake or pond is home to a variety of phytoplankton, and zooplankton, which play an important role in the food chain. Other areas of still waters, or wetlands, such as glades, swamps, and marshes support a variety of aquatic flora and fauna. Aside from plants such as sedges and pond lilies, the wetlands also support a few trees, such as cypress, which are highly adapted to the high humidity of these regions. The wetlands are rich in life forms, from reptiles, to mammals, to amphibians and birds, to hundreds of insects.
When the snow on the mountains melts the water flows into streams and rivers and ultimately each of these rivers or streams end up in the ocean or other waterways. Since this water is in constant motion, the flora and fauna that grow within are very different. Some fish, such as the trout, and small scavengers such as crayfish can be found in various rivers, whereas plants include floating weeds and algae, mostly found forming around rocks and submerged tree roots.
The marine regions are divided into coral reefs, estuaries (where freshwater meets saltwater) and oceans. Oceans represent the largest and most diverse of the ecosystems; salt water evaporates and turns to rain which falls on the land regions, while most of the oxygen in our atmosphere is generated by algae. Algae are also responsible for the absorption of large amounts of carbon dioxide from our atmosphere. In the warm shallow waters, which line the continents and surrounding islands, lie barriers called coral reefs. Coral is a living organism that consists of both animal and algae tissues. The coral reef is also host to other species such as starfish, octopus, and other mollusks.
Sea is a host to silt, sand and organisms that slowly decompose. This area is very cold due to its depth, which remains untouched by the light of the sun. There are few plants at this level, and the animals include mostly bottom feeding organisms such as starfish, anemones, sponges, amongst others, as well as various micro-organisms.
Marshes can be defined in much simpler terms as wetlands frequently or continually inundated with water. The main feature being soft-stemmed vegetation that is adapted to its moistened soil conditions. There are many different kinds of marshes, ranging from the grassland potholes that allow water to flow in from the coasts to the inlands. This exchange also takes place from freshwater to saltwater.
Whatever the kind, most of these receive water from the water surface, but there are also marshes that rely on groundwater. Its soil is rich in minerals and that is one of the main reasons that we find plants here in abundance.
These plants attract large number of fishes and animals. These marshes act as a filter and clean the water. When the water reaches the marshes its speed is slowed down as large reed beds acts as a barrier and separates the mud and silt. The Marsh has a variety of vegetation which includes large fragmities (common reed) reed beds, red gum forests and areas of lignum, coolibah and water couch, all of which are needed to provide nesting and feeding grounds for water birds. Animals that inhabit this area are fish, birds (herons, egrets, anhingas, spoonbills, ibis, etc.), frogs, snakes, mammals and small reptiles.
These are various tropical shrubs, plants and trees that you find having stilt-like roots and stems found usually along the tidal shorelines. It is estimated that almost 75 per cent of the fish are caught here. Most of the plants are unable to grow in saltwater, mangroves has no such problem. Mangroves provide the shoreline with protection from wind, waves and floods. The animals found here, are fish, crabs, shrimps, jellyfish, crocodiles. Insects such as mosquitoes and flies are also found in great abundance here.
Like some other biomes tundra can also be distinguished into two sub-biomes, Alpine Tundra and Arctic Tundra. Alpine Tundra are located high in the mountains world-wide, above the tree line and takes about 180 days to grow. At nighttime the temperature falls below freezing point. The soil is well-drained (unlike the Arctic Tundra).
The Arctic Tundra is a vast and treeless stretch of land which covers about 20 per cent of the Earth's surface. It is usually very cold, and the land is almost without vegetation. It's located in the Northern Hemisphere. Small tundra-like areas do exist in Antarctica in the Southern Hemisphere, but because it is much colder than the Arctic, the ground is always covered with snow and ice. Here weather conditions are not conducive for tundra formation. Average annual temperatures fall between -70°F (-56°C). The word Tundra comes from the Finnish word "tunturia", which means a barren land.
Some of the plants that are found here are Arctic moss, Arctic willow, bearberry, caribou moss, Labrador tea, etc. while animals that inhabit this biome are elk, marmots, mountain goats, pikas, sheeps, grouse-like birds, beetles, butterflies, grasshoppers, and springtails.
Taiga is the Russian word for forest. Taiga is the largest biome in the world. It stretches over Eurasia and North America. The taiga is located near the top of the world, just below the tundra biome. The winters in the taiga are very cold with heavy snowfall. The summers are warm, rainy, and humid. A lot of coniferous trees grow in the taiga. The taiga is also known as the boreal forest.
The taiga doesn't have as many plant and animal species as the tropical or the deciduous forest biomes. However, it does have millions of insects in the summer time. Birds migrate there every year to nest and feed.
Some plants that grow here are Balsam Fir, Black Spruce, Douglas-fir, Eastern Red Cedar, Jack Pine, Paper Birch, Siberian Spruce and White Poplar. While the animals found here are American Black Bear, Bald Eagle, Bobcat, Canadian Lynx, Gray Wolf, Long-Eared Owl, Red Fox, River Otter, Snowshoe Rabbit and Wolverine.
World Biomes Summarized
- Natural Regions Of The Earth
The surface of the Earth is divided into twelve natural regions. These regions have been categorized on the basis of surface features, climate and vegetation.