Biomes are classified according to the climate and geography as well as being heavily influenced by oceans and ocean systems. Latitude has a strong influence on a biome. Areas closer to the equator receive stronger solar radiation for longer periods of time, further north or south from the equator receives far less energy for reduced lengths of time; the varying amounts of sunlight create different seasons and weather patterns. The presence of oceans and currents also contribute to temperature changes and moisture levels, the two influences constantly react with each other creating unique climates and weather patterns to the area.
The influences create specific environments for life to grow in; the rates and abundance of growth depend of the characteristics of the biome and will vary immensely from one biome to another.
There are 7 major world biomes:
- Tropical forest
- Desert
- Temperate broadleaved forests
- Coniferous forests
- Grassland
- Tundra
- Ocean
Tropical Forests
Found in:
- Central America
- South America (Amazon)
- East Africa (Madagascar)
- Africa (Congo River basin)
- South East Asia
- Australia (Queensland)
Tropical forests occur along the equator (up to15-25 degrees north or south) and so receive very direct sunlight all year round. Due to the central position, these areas of land constant levels of sun with 12 hours days constantly throughout the earths orbit. Temperatures average at 77 degrees Fahrenheit
The incredible heat evaporates large amounts of water and once they have risen and cooled, condense to form clouds. 50% of the rain that falls in rainforests comes from its own evaporation and not carried in or out by winds. North and South equatorial currents circulate warm water away from the equator and bring in cooler waters, as the water gets closer to the equator it rapidly heats, creating masses of evaporation. Rainy seasons are dependent on whether the northern or southern hemisphere is facing the sun. Rainforest experience about 2.5 meters of precipitation a year, this coupled with large amounts of solar energy creates an environment for rapid and large growth.
Rainforests make up 6% of land surface and are home to over half the population of all plant and animal life on earth (over 15 million species). The most abundant group found in rainforests are trees making up 70% of all species in the rain forest.
The soils are often nutrient poor in rainforests because nutrients are leached away by periodic precipitation and the abundant life here means they are highly competed for. The lack of light that penetrates the canopy means little life survives on the forest floor, all the activity goes on high in the tree canopy. These conditions are ideal for bacteria and fungi making the decomposition process rapid, this also adds to the reduced nutrient availability in the soil.
Vegetation
Strangler Fig (Ficus ssp)
This is the name given to species of figs that exert the following characteristics. Figs are an important part of the food chain in the rainforests and a constant source of food as they fruit several times a year. Strangler figs are tall canopy trees (up to 148 ft) with light bark and waxy ovate leaves that protect the tree from too much sun evaporation from sun and wind.
Strangler figs start out as epiphytes attached to a host tree; they rely on the tree for stability but not for nutrients. The fruits are eaten by animals and birds and are deposited higher up in the trees. The figs use water that has collected on the tree and catch more sunlight, as it grows further up. From its height the fig sends out roots that suspend from branches, once they reach the ground they take root and start draining nutrients from the soil and are very direct competition with the original host tree. The fig then starts to send out a network of shoots that envelop the host and fuse together. Gradually the roots encompass more of the tree and squeeze tight around it cutting of its circulatory system. Once the fig reaches the canopy it branches out across the canopy in an umbrella shape with lots of small leaves. The host tree, now internally damaged and out-competed for nutrients and light, dies.
Strangler figs have a very unique symbiotic relationship with a species of wasp (Aggaoninae ssp), the reproductive process is complex and very specific and without it the strangler figs would cease to exist.
Fig trees in the rainforest are at threat due to excessive logging regimes and fires, further loss of populations could have dire consequences for the many species of bird and animal that feed from its fruit all year round.
Mangrove Forests
Mangrove forests have specially adapted to live on the edge of rainforests where the forest meets with the ocean. They protect species further inland by slowing the flow of water and collecting sediment and salt. Mangroves account for 39.3 million acres of coastline across rainforests, 27% of these are in Southeast Asia where they are thought to originate.
Specialised aerial root systems hold the trunk of the tree over the water; support roots are buried into the mud for stability. The trees can survive in waters of high salinity because their aerial and tap roots filter out salt, salt taken in by the tree is stored in the leaves and is shed periodically.
Seeds of the mangrove germinate and grow into seedlings on the parent tree, eventually they are dropped and will either take root in the mud or will be swept out with the tide and take root somewhere else. The seeds are hardy and can travel vast distances from the parent tree before taking root
These forests support a wide variety of life and have their own environments and ecosystems within the biome. They are breeding grounds for an assortment of marine animals such as fish, shrimp, prawns, shellfish and snails. They provide nesting nesting sites for many shore birds and are home to crab eating monkey and proboscis moneys as well as fishing cats, lizards, sea turtles and fruit bats.
All these species rely heavily on the mangrove forests and yet they are under threat from human activity. Mangrove forests act as sinks for pollutants, crude oil, sewage and toxic materials build up in the waters around the trees, the presence of all these products put to much stress on the trees and they die. Mangroves also make good charcoal and so are at threat from logging to feed a growing industry. The loss of mangroves not only means a major loss of bio-diversity, but also leaves inland forest and land open to damage from salinity and coastal weather patterns that they are not adapted to deal with.
Animals
Howler Monkeys (Alouatta spp)
Howler moneys are primates that are native to Central and Southern America, there are 9 species recognised. Howler monkeys are the loudest land animal, they are second in volume only to the blue whale and can be heard up to three miles away.
Howler Monkeys are found in:
- Southern Brazil
- North Argentina
- Paraguay
- Bolivia
The species have specially adapted to life in the rainforest, spending pretty much all there time in the trees howler monkeys have developed long prehensile tails that act as another limb when moving around the canopy. The hands are specially adapted with the first two fingers being separate and opposite from the other three; this helps with gripping and moving on branches. The monkeys diet consists mainly of canopy leaves with some ingestion of fruit, flowers, buds and maggots to supplement their diet.
Howler monkeys live in the canopy in small social groups of about 15 to 20 animals, they communicate through vocals and can make the forest vibrate with their calls. These monkeys are very gentle despite their loud manner and can live to 20 years. They do not survive well in captivity and are very much a monkey of the rainforest canopy.
Howler monkeys are in decline and are under threat from habitat loss due to excessive logging for timber, which is shipped across the world and sold by many popular retailers.
Slender Loris (Tardigradus malabaricus)
This small primate is native to the tropical rainforests of South India and Sri Lanka and tends to live along the edge of the forest in wet or dry conditions. They prefer the cover of thick thorny vegetation, which provides them with protection from predators.
Slender Loris are small weighing about 275-348g, they have light red to brown fur on their backs and pale fur on their fronts. The arms and legs are long and very slender with the hair becoming very thin around the forearms, hands and feet. The lack of hair helps them when hunting; they stretch their arms through the twisted thorny vegetation to gram unsuspecting insects. The Loris has a short vestigial tail, which offers little balance, and so all movement is slow and calculated. The second finger is short on both hand and foot and works alongside the thumb, this helps with holding onto branches in the high unstable canopy.
Slender Loris are insectivorous which means their diet mainly consists of insects but they are also know to eat slugs, leaves, flowers, shoots and occasionally eggs. They hunt alone or in pairs but will share food and live in small social communities in tree hollows. They rarely leave the safety of the canopy and are seldom known to use the rainforest floor.
Interestingly the slender Loris have a taste for toxic insects and will regularly eat insects with poisons that could numb a mans arm.
As with so many rainforest creatures the slender loris are under threat from habitat loss due to excessive logging.
Dessert
There are two types of desert biome ‘hot and dry’ and ‘cold’, both types characteristically have very little or no vegetation and highly specialised animal species.
Hot and Dry Deserts
Found in:
- North America
- South Asia
- Africa
- Australia
Hot and dry desserts are found near the equator and are generally found along the tropics of Capricorn and Cancer. These deserts cover a fifth of the lands surface but are home to few species of flora and fauna. Temperatures in the hot and dry dessert are somewhere between 20-25 degree centigrade, maximum extreme temperatures occur up 45 degrees and the temperature fluctuates little over the year because of its latitude. The spring and autumn is warm and summers are very hot, the temp cools little over the winter months, there is very little rainfall in the area in general, even winters bring little or no rain.
Vegetation in hot, dry deserts is rare, any vegetation that does survive needs to be able to store its own water and nutrients and be able to withstand the suns radiation. Any vegetation that manages to grow in this hostile environment are usually ground hugging shrubs and small woody trees.
Animals that live in this barren hot environment need to have the ability to burrow into the sand, this helps them to keep cool during the hot days and they will then venture out at night when it is cooler. The creatures most likely to be found in this biome are nocturnal carnivores, insect, arachnids, reptiles and birds.
Cold Deserts
Found in:
- Antarctic
- Greenland
- Nearctic realm
- Atacama (Coasts of Peru and Chile)
- Gobi (Northern China and Southern Mongolia)
- Great Basin (Western United States)
Cold deserts are found near the arctic, temperatures are so low that no vegetation can grow with the exception of a few mosses, lichen and grasses. Temperatures at this latitude vary greatly with summers reaching up to 20 degrees centigrade and winters averaging from –2 to 4 degrees. Spring and summer never get warm enough for plants to establish and winters bring long months where the ground is covered in snow, this makes difficult conditions for life.
As with hot deserts, cold deserts have little vegetation, the plants that are present are scattered and ground coverage varies from 10% - 85%, once established the brush can reach 15-122cm high, these are mainly deciduous and many have spiny leaves
Some animals found here also have to burrow as do those species in hot, dry deserts, but this time it to keep warm not to cool. Typical animals of cold deserts are, antelope, ground squirrels, jackrabbits and kangaroo rats.
Vegetation
Barrel Cactus (Ferocactus ssp)
This cactus is common in dry desert areas, they are native to North America, predominantly the Mojave Sonora and Chihuahua deserts. It has a cyndrilcal body 5-11feet round. The cactus has parallel ridges running down the sides with 3-4inch spines. It is a flowering cactus with green/yellow/red rings of blossoms that bloom in summer.
They store water and nutrients in the plant but actual water requirements are very low, filled with a slimy alkaline juice. The pulp can be made into a sweet food and Native Americans use the spines for fishing hooks,
Common Salt brush (Atriplex polycarpa)
Common salt brush is a common plant to the colder deserts of North America. It is a greyish shrub with many branches coming out from the base. The small white leaves cover the branches closely and are sharp spines clustered densely over the shrub, this helps to conserve water. Yellow flowers grow out from the stem. These plants can reach 2-3 feet and are very well adapted to the dry alkaline soils they are found in.
This plant has adapted over time to its dry conditions and is now a plant that actually favours dryer areas and does not tolerate wetter soils. Salt brush gets its name because it stores salt taken in from the soil in the leaves, which leave white deposits, these help to attract moisture from the air. The leaves are periodically shed to rid the plant of salt and also conserve moisture in times of drought.
This is a useful plant and is a good source of minerals for cattle, deer, rodents and pronghorns. They are a good shelter for birds and animals and can be used as a perch for larger birds. The plants are used by people for food and as a yellow dye.
Animals
Camel (Camelus spp)
There are two types of true camel in the world and both are found in hot deserts, these animals are so well adapted to life n the desert nearly all their characteristics are ideal for surviving in hot, dry barren areas. They are native to the dry and desert areas of Northern Africa and Asia,
Camels are quite distinctively identified by their humps the Arabian camel (Camelus dromedaries) has a single hump, and the Bactrian camel (Camelus bactrianus)) Camel has two humps. The hump is a reservoir for fatty tissue, when energy is needed the fat is metabolised, this process also produces water with the reaction of oxygen with metabolised fats. This means that camels can go weeks without water and up to a month without food. This makes them perfect animals for surviving long journey across arid desert.
The blood cells of camels have an oval shape, this shape means that cells do not explode when large amounts of water are taken in, it also helps to prevent dehydration. Camels retain most of their water and urine is thick syrup pretty much void of water and apparently faeces is so dry it can be used as fuel for fires.
The fair colored coat of the camel reflects sunlight helping it to keep cool and the legs are long to keep the body away from the hot sand. Camels can actually withstand body temperature changes above the normal level for mammals, fluctuating from 34 degrees C at night to 41 degrees C in the day.
Camels have long eyelashes, lots of hair around ear openings and nostrils that can close, these all help camels to withstand windblown sand.
Camels are now mostly domesticated and very few native species exist in the wild. There are 1.4 million domesticated Bactrian camels and only 1000 wild. Arabian camels have a population of 13 million all of which are now domesticated. A feral population of camels descended from camel taken over during the 1900 is now rife in Australia with a population count of 700,000, the Australian government have decided to start culling the population because they are using up limited resources need by farmers.
Desert Kangaroo Rat (Dipodomys deserti)
The desert kangaroo rat is one of 22 species of kangaroos rat recognised worldwide that has adapted to desert conditions. It is small (35cm including tail) which means it does not require much water for survival. The coat is light brown/yellow on top and white on the underside. The rat has large eye because of its nocturnal activity.
Most of the day is spent sleeping underground, the kangaroo rat build a series of tunnels and chambers below the surface where it is cooler. It comes out at night at periods when the air is cooler and moister.
The diet consists of seeds, leaves, stems and insects, the digestive system is adapted to convert food into water, and this improves chances of survival. The kangaroo rat has a specially adapted cheek pouch that can store food for several weeks.
This species is abundant and is not endangered.
Temperate Broadleaved Forests
Temperate broadleaved forests are highly diverse places with various levels of growth the characteristics of these biomes are tree which shed their leaves in winter.
Found in:
- North America
- Middle of Europe
- Russia
These biomes are found at latitudes up to 23 degrees north and 38 degrees south, their positioning gives them varying periods of solar energy throughout the year; this gives these areas 4 distinct seasons (spring, summer, autumn, winter). Summers are characteristically mild and winters are relatively cool. These forests are mostly found close to oceans and this has a large effect on the temperature and precipitation in the area. Temperate broadleaved forests typically experience 14 inches of precipitation in winter and 18 inches in summer. Temperatures vary from –30 to 30 degrees but these extremes are rarely experienced in most places.
These forests are very diverse places with plants grown occurring at many levels and the presence of large numbers of plant species, the soils of temperate broadleaved forests often being nutrient rich. Due to the cooler winters, many animals in temperate broadleaved forest have adapted by hibernating through this season.
Species of plants typical to these areas include such species as Maple (Acer spp.), Beech (Fagus spp.), Oak (Quercus spp.), Hickory (Carya spp.), Basswood (Tilia spp.), Cottonwood (Populus spp.), Elm (Ulmus spp.), and Willow (Salix spp.). Squirrels, rabbits, skunks, birds, deer, mountain lion, bobcat, timber wolf, fox, and black bear represent fauna.
Vegetation
Oak (Quercus spp)
Oak trees are a dominant species in temperate broadleaved forests, there are hundreds of species considered to be Quercus but not all are true oak species. Oak as a Genus are native to the northern hemisphere, namely North America. The oaks can be split into 3 large groups, evergreen oaks, red oaks and white oaks, all species have similar characteristics from bark to leaves but each species has its own adaptations to changes in soil, temperature, weather patterns etc.
Oaks characteristically have lobed leaves, these can be softly lobed or serrated and some even have a single leaf outline. These trees being native to temperate regions shed their leaves during the colder months, this helps the tree to conserve moisture during the dryer season and also help the tree to shed excess toxins that have been stored in the leaves.
Oaks are important trees for the surrounding wildlife, as they tend to be a breeding ground for insects and share symbiotic reproductive relationships with a few particular species of wasp. The popularity of the oak amongst insects attracts larger birds and animals to these trees to feed. It is also a popular tree with birds and small mammals. Due to their longevity oaks are very popular trees for people, they can live for up to 1000 years if undisturbed and are majestic and strong trees that provide beautiful scenery, despite this oaks are on the decline because of changing land uses and the growth of the logging industry.
Carpet Moss (Mnium hornum)
This species of moss (one of thousands) is very common among the temperate broadleaved forests of North America and Europe. This moss will be found almost everywhere that you would find deciduous woodland. It is a simple rootless evergreen plant that will be seen growing on the ground, in streambeds and at the base of trees. The moss likes to be constantly moist and so absorb water through pores, which are continually open.
Carpet moss reproduces both sexually and asexually this means that reproduction occurs with eggs and sperm and fertilization. The simple plant can also reproduce if cut of from the main body of the plant. This gives moss a really good chance at establishment.
Mosses in general are resilient and hardy they rarely need to adapt too much to suit a specific area and are found in pretty much any environment on the planet.
Animals
European Red Squirrel (Sciurus vulgaris)
The European red squirrel is native as its name suggest to Europe, it is a tree dwelling omnivore and is part of the order Rotentia. The red squirrel is small in size and weighs about 250-340g it lives among the canopy of deciduous forest but are also know to move around the forest floor. They are red to brown in colour with white undersides; both males and females are the same size.
Red squirrels are adapted to their forest environment with large bushy tails that help with balance and also keep the animal warm during the colder winter months. The squirrels have specially jointed legs to improve mobility up and down tree trunks and their hands and feet are clawed for grip.
Squirrels shed their fur twice a year, in the summer they lose a warm winter coat and vice versa in the winter; this is to keep the animal at a stable temperature with the fluxuating temperatures that exits in a temperate broadleaved forest.
Unlike many animals of these environments, squirrels do not hibernate, they deal with the lack of food during the winter month by storing food, they will collect fruits nuts and seeds throughout the proliferous summer months and keep them hidden until needed. When the temperature drops right down the squirrel will not leave its nest (known as a drey) for several days without leaving and so need to have some source of food at this time.
Squirrels are important to their environment because they help to spread seeds from trees and shrubs when the digest and pass on the foods they have eaten.
European red squirrels are common in most of Europe except for Britain where the species is in massive decline and most know live farther north in Scotland. This is down to competition with the introduced American grey squirrel and habitat loss from land use change.
Coniferous Forests
Found in:
- North America
- Asia
- Northern Europe
Average temperatures in these areas are very cold. Winter is the longest season and during this time temperatures range from –54 to –1 degree centigrade. The weather is dominated by snow but there precipitation is generally low. The summers are short but get very warm with temperature ranging from –7 to 21 degrees, most precipitation falls as rain during the summer. Spring and autumn are short and cold.
The temperature and weather make coniferous forest biomes very harsh places and not much life survives at the cold temperatures. The vegetation is mainly made up of lichen, moss and conifers (pine, spruce, hemlock and fir) these forests darken the forest floor so there is little ground vegetation. Few animal species live in this tough environment; the animals most likely found are lynx, wolverines, bobcat, mink and snowshoe rabbit. This area is home to many insects and thus attracts birds such as finches, sparrows and crows. All species of flora and fauna need to show special adaptations to survive the difficult surroundings.
Vegetation
Conifers (Division: Pinophyta)
Conifers belong to the Class (Pinophyta), they do vary from species to species and some are more tolerant of others but in generally there are many similarities that all species have adapted to survive. Conifers tend to be tall trees, their long thin needles are shaped to protect the tree from evaporating and are waxy to protect from the cold. The needles on coniferous trees do not fall in the winter like broadleaves, they stay on all year; this means that these trees can absorb the suns energy from the earliest time possible.
Trees often grow tall and close together the height gets them closer to the sun to improve absorption and the dense growths of forests protects tree from harsh winds. The roots on conifers are shallow; this is to deal with the shallow, nutrient poor soils. The shape of the tree is well adapted to snow, the sloped limbs let snowfall of and onto the ground, and the weight of the snow if allowed to build up would damage the tree,
Conifers reproduce mainly through the production of seeds in cones, these form on the branches of the tree and develop over months. Eventually the cone opens and the seeds are dispersed onto the ground or a carried away on the wind. Some species (Pinus) take advantage of the presence of birds and pass their seeds on through food.
Animals
Bobcat (Felis rufus)
The bobcat is a carnivorous cat found mainly in the coniferous forests of Canada, larger than a house cat it weighs from 6-10kg and is known by its characteristically short tail. The bobcat had adapted to the coniferous forest in several ways, its coat is dense and keeps the cat warm during the long winter months. The bobcat’s coat also changes colour to suit the season. During winter when there is more snow and everything is lighter, the bobcat’s coat is tawny and grey. During summer the coat turns a reddish brown. The coat is always stripped or spotted. These features help bobcats to remain camouflaged while they hunt.
The cats have long sharp teeth and claws for tearing the flesh of their prey; they hunt silently and normally catch their prey in one pounce. The ears are able to swivel on the head, this allows the bobcat to hear prey all around, this is essential for its survival during the coldest months when food is most scarce.
Grizzly Bear (Ursus arctos horribilus)
The grizzly bear is a sub species of the brown bear which lives in areas of North America. The grizzly bear is very suitable to the environment of a coniferous forest and have adapted several features to aid their survival.
These bears are large mammals that can reach weights of 680kg, the diet consists of mainly plants (makes up 75% of diet) but bears are omnivorous and so are also known to eat insects, honey, small rodents and mammals and even carcases. To find food under the snow the grizzly bear needs to be able to dig, it has adapted a large muscular hump on its back to power the limbs when digging. This makes scavenging for food far more energy efficient. The paws also have large claws that help the bear to dig up hard soil.
The grizzly bear has a very thick coat that keeps it warm all year and helps to regulate temperature during the hibernation period. The coat also varies in colour from area to area suggesting that it helps with camouflage.
The bears also need to conserve energy during the coldest winter months, to do so they go into a state of false hibernation. It is not a true hibernation as the heat rate and temperature do not decrease by much and they are easily roused from their sleep, but it does conserve energy for the bear. Before the hibernation the bear will gain hundreds of kilograms in fat stored on their body. During the hibernation this fat is converted to energy.
Grassland
Found in:
- North America
- South America
- Asia
- South Africa
Grasslands can be divided into different types, some are tropical and wet and others dry, the defining features of all of them is that grass dominates the landscape with little or no wood plants to be found and precipitation level is between 25 –75 cm. Grasslands tend to have two distinctive seasons a growing season and a dormant season, the summer brings warm temperatures and increased rainfall (but not enough to support trees and shrubs). During this time grasses spur into life from the effects of the sun and increased precipitation.
Wet grasslands are dominated by tall grasses and have moist, humid climates; the increased precipitation from evaporation allows these grasses to grow to heights of 6-10 feet.
The dryer grasslands experience bigger extremes of temperature and weather can be very erratic. Grassland temperatures can vary through out the year (–40 degrees F to 70 degrees F from winter to summer). Long periods of drought commonly cause fires in dry grasslands. The grasses are able to withstand fire damage because they grow from the top and not the bottom so can recover quite well in the aftermath of a fire.
The lack of cover from trees and shrubs means that wind blows straight through grasslands making them seem very windy, plant and animal species need to show special adaptations to dealing with low levels of precipitation, strong winds and varied temperatures.
Vegetation
Blue Grama Grass (Bouteloua grasilis)
Blue grama is a common grass associated with both tall and short grasslands of central North America. The plant can reach a height of 18 inches and grows in tufted bunches close together to form sod mats. The leaves of this grass are flat and grow to 1-10 inches out from the base. Flowers (which bloom jun–aug) grow from 7-18 inches and the ends look like crescent moons.
These plants are well adapted to grassland environments and can withstand the effects of drought, heat, cold, fires and grazing; they cope well and even prefer being in full sunlight. Blue Grama Grass has shallow roots, which allow the plant to absorb water quickly when it does rain. The shallow network of roots actually helps to bind the soil together and prevent it from being eroded by wind.
This grass is easily damages by ploughing; once the roots have been ploughed it can take decades for the plant to re establish. Blue grama can survive well in dry grasslands due to its ability to enter a dormant state during the cold dry winter and droughts.
Pampas Grass (Cortaderia selloana)
Pampas grass is a common tall grass of the flat plains of South America; this is a wet grassland area with larger vegetation than dry areas. Pampas grass can grow up to 12 feet tall; it grows in tussocks with dark green razor sharp leaves that extend up to 10 feet. This grass is well adapted to the warm damp climate of South America but can infact survive in almost any habitat, it grows well in sun, on damp or dry ground, deep or shallow soils. Its ability to adapt well to its surroundings makes it an abundant and dominant species in certain areas, its size shading out other vegetation.
During the colder winter months, the long leaves die back during frosts, the leaves then re-grow in spring. The key to pampas grass survival is its roots, the plant sends out deep root systems that dig down into the soil to gain access to water where other plants cant reach, meaning it can survive in even the driest of areas.
Animals
Coyote (Canis latrans)
Coyotes are members of the dog family that live in grasslands (as well as other habitats) in North America. The coyote’s features are similar to that of a wolf but coyotes are much smaller than wolves with a longer nose and ears. The coyote’s coat is generally grey to brown/yellow; the coats hues help the animal to camouflage in the long grasses when hunting or hiding.
The coyotes are well adapted to live in these often species poor dry conditions, this starts with their diet, coyotes are omnivores and will eat almost anything they find in their surroundings. In the grasslands of North America a coyotes diet mainly consists of rabbits, birds, gophers, prairie dogs, rodents, fruit and grasses. Coyotes will live in pacts but generally hunt alone, they can spend up to half an hour stalking prey through the grass with their incredible scene of smell before pouncing. They originally locate prey by rotating their ears back and forth to pick up the slightest sound.
As with many species of animal that live in wide open flat grasslands coyotes can run pretty fast either to catch prey or flee from danger and can reach speeds of up to 40mph.
During the winter months, coyotes survive by eating remains of dead animals and berries if normal food sources are scarce. The variable precipitation levels means that coyotes also need to be able to receive water through their diet and so supplement their diet with water bearing fruits in time of drought.
Saiga Antelope (Saiga tatarica)
Saiga antelope can be found on dry steppe grassland and semi-deserts around Mongolia, Kazakhstan and Kalmykia. This antelope is extremely well adapted to both the cold and dusty environment of the grasslands it inhabits. The large distinctive nose of this species serves functional essential to the saiga’s survival, during them summer months the complex nose structure filters out dust kicked up to protect its lungs and during the winter the nose heats up air before it is taken into the lungs; this allows the animal to conserve energy that would otherwise be lost through having to warm itself.
The coat of the Saiga antelope changes to suit it environment, during the summer the coat is tan and matches the golden/cinnamon hues of the grassland. During the winter the coat turns almost white and becomes 70% thicker with a warm woolly undercoat covered with a course protective overcoat. The two coats keep the animal warm when temperatures drop and protect from chilling winter winds in the open plains.
Saigas are herbivores; their diet is made up of mostly grasses, saltwort, sagebrush and lichens. These animals chew cud to extract as much nutrition as possible from the plants they eat.
Tundra
Found in:
- (Arctic Circle)
- Canada
- Greenland
- Russia
- Northern Europe
- Alaska
Tundra is vast, cold and stark, it exists at latitudes of 55-70 degrees north close to the Arctic Circle and covers nearly 20% of the lands surface, this is the coldest and driest of all the worlds’ biomes. At these latitudes the difference between seasons is massive. There are two main seasons, summer and winter, spring and autumn are so short that they are barely recognised as their own season.
During the winter, the land is dark for most of the time and the sun barley rises in the sky, temperatures can drop as low as –70º C, the ground is permanently frozen up to 100cm below the surface (permafrost). In summer temperatures sit between 3º-16ºC, the sun is visible for most of the day; this causes some of the ice to melt, resulting in a land covered with lakes, bogs and marshes, (the water cannot penetrate the frozen ground beneath).
Due to the freezing temperatures and lack of precipitation (just 6-10 inches a year!), very little can grow in the tundra and the landscape id dominated by low growing plants such as moss, lichen, heaths and small shrubs, there are virtually no trees save a few scattered low growing birches and willow; the lack of tall vegetation makes this a very windy open space.
The extremely harsh environment means that few species of flora and fauna inhabit the tundra, it is a very species poor area as for any species to survive here they need to have made some drastic adaptations. Some of the species that have been able to do this are, shrews, hares, rodents, wolves, foxes bears, deer and caribou. During the summer, the melted ice attracts species of insect and migrating birds such as harlequin ducks, sandpipers and plovers.
The tundra is a carbon dioxide sink, this means that it absorbs more CO2 that it puts out, this is because that it too cold for plants to decompose and release CO2 when the die. The reduction in ice volume that is occurring in the tundra is causing large amounts of stored CO2 to be released to the atmosphere.
Vegetation
Arctic Moss (Calliergon giganteum)
This moss exists within the Arctic Circle in tundra biomes. It is an aquatic plant that forms in the many lakebeds, fens and bogs across the tundra surface. This is a very common plant in theses environments due to its slow growth, cold resistance and ability to store nutrients.
Arctic moss is a bryophyte, it is non-vascular and does not circulate fluids, and this helps the plant to survive in these harsh conditions. The plant reproduces via shoots and spores that need to be kept moist to survive.
The arctic moss is a very slow growing plant, it average growth is 1cm a year, this is in reaction to the reduced growth period in the tundra (50-60 days a year), the leaves live for up to 4 years and shoots up to 9 years.
During the winter the moss goes into a period of dormancy, it stores nutrients so that when the sun comes it can start to grow quickly to utilise the most of the short summer. Living underwater the moss is protected from the strong winds on the surface; its roots carpet and warm the ground, which prepares the ground for other plants to grow.
Arctic Willow (Salix arctica)
Arctic Willow is one of the few tree species that can inhabit the arctic tundra, mainly found in North America, North Canada and North Alaska; this plant thrives in the cold, dry climate of the tundra. It is generally found in cold, dry open places as well as sedge meadows and edges of pools.
This tree only grows to a height of approximately 15-20cm and tends to hug close to the ground to protect itself from strong winds. The leaves are small, oval and pointed, with light green tops and dark green undersides. The leaves have adapted to the cold by growing hairs, which help to prevent evaporation or freezing.
This tree does not have any taproots, only shallow lateral roots. This is because the ground is frozen so close to the surface that no roots could penetrate far down the flowers are unisex and bloom in spring so there is enough time spent in summer to gather energy, the tree uses the constant wind presence to help reproduce as the flowers are forces upwards where they are blown by the wind.
During the summer the tundra is infested with insects all wanting to feed on low volumes of vegetation, the arctic willow protects itself by producing a pesticide to keep insects away so it can grow.
Animals
Caribou (Rangifer tarandus)
Caribou are often more popularly known as reindeer, they inhabit arctic and mountain tundra in places like North Greenland, Scandinavia and Russia. Caribou are members of the deer family, they stand up to 120cm at the shoulder and unlike most deer both males and females have antlers.
Caribou coats are lightweight with hollow hairs, this helps to trap heat close to its body, during the summer coats are dark brown in colour getting lighter towards the winter, they have long ruffs of hair under their necks to help keep warm. The hooves have adapted to suit the unstable ground, they are large and spread, so the caribou can walk competently on snow and through marshy ground.
Caribou can survive in even the harshest of climates, they migrate 100s-1000s of miles to find feeding grounds, travelling in massive herds helps to keep them warm. When vegetation is scarce caribou seem to be able to smell plants under the snow and dig with their frost paws in the snow to get at food. One of the most useful adaptations of the caribou is its ability to lower its metabolic rate and go into a state of semi-hibernation to conserve energy when conditions get really harsh
Snowy Owl (Nyctea scandiaca)
The snowy owl is found in circumpolar tundra, it breeds on coastal areas of Alaska, Canada, Greenland and northern parts of Scandinavia and Russia. These birds like areas of open tundra from sea level to elevations of about 300m.
The snowy owl has very light feathers from cream to grey to white, the feathers are also marked with dark spots and stripes, this provides birds (especially females) with camouflage when nesting and incubating eggs. The owls’ legs and feet are also covered in feathers, which keeps the animal warm through the coldest months.
Snowy owls are carnivorous and feed on a diet of mainly lemmings and mice but will also eat if available, rabbits sea birds and fish. They sit at an elevated point and watch and listen for signs of prey, both sight and hearing are highly attuned and the owl can swivel its head round 270º to view a vast area. The claws are long and sharp, which can tear apart a small mammal in an instant. Unlike most owls, snowy owls are diurnal which means they are active throughout the day.
Snowy owls are known to migrate south in periods of reduced food availability but always return to their northern homes in spring.
Ocean
This marine biome is the largest on the planet as oceans cover 70% of the earths surface, the four oceans are:
- Pacific Ocean
- Atlantic Ocean
- Indian Ocean
- Arctic Ocean
The oceans have an average temperature of 3.8º C, but it is hard to gage a true figure as water is constantly moving, mixing, heating and cooling. The temperature of oceans varies massively from place to place, near the equator they are constantly warm and clear whilst near Polar Regions the water is so cold that the surface is frozen.
There are 4 zones to oceans;
Intertidal - this is where ocean meets land this could be rocky coats or beaches, the landscape of this area is constantly changing from the effect of tidal movement, the waters are warmer here than anywhere else as the shallow waters heat faster and are effected by land temperature. The usual inhabitants of intertidal areas are; snails, crab, starfish, invertebrates, seaweed, algae and molluscs.
Pelagic – this is the surface water further from land, the water here is deeper and cooler than intertidal areas, there is less diversity in this area with floating seaweeds and plankton being the dominant vegetation, fish, whales, and dolphin come here to feed.
Benthic – this zone lies below the pelagic and waters continue to get colder the deeper the water. This zone has a bottom layer of sand, silt and dead organic matter; these deeper waters receive less light and are abundant in species such as bacteria, fungi, sponges, anemones, worms and fish.
Abyssal – This is the deepest zone of the ocean, it is also the coldest and darkest. At these depths the water pressure is very high, abyssal zones are high in oxygen but low in nutrients and are abundant with species of fish and insects.
In addition to the 4 oceanic zones there are two other areas that are part of the marine biome:
Coral reefs – these occur in warm, shallow waters and are often located along the edges of continents, the dominant species here is obviously coral. Coral is made up of algae and polyp, which work together for food and energy. As the nutrient level in the bottom is so poor corals gather energy from algae photosynthesis as well as the polyps sending out tentacles to eat plankton. Coral reefs are home to many species of invertebrates, fish, urchins, octopus and starfish.
Estuaries – estuaries exist where ocean and freshwater meet, often through rivers and streams, here the waters mix giving varied salinity to the water. This creates a unique environment that supports large communities of algae, seaweed, marsh grasses and invertebrates; this attracts many species of bird to estuaries periodically.
Vegetation
Seaweeds
There are about 10,500 species of seaweed in the ocean; they are grouped into 3 types, green, brown and red. Seaweed needs two factors to exist, seawater and sunlight. Seaweeds are photosynthetic algae and are not considered true plants, as they do not have a vascular system, they are generally found on rocky shores and close to the land, this is because the water gets too dark further out for them to survive.
The seaweed needs to have a firm point of attachment, this is either the ocean floor or a rock so it does not float out to sea and perish. Despite this some species of seaweed have actually adapted and become free-floating with the aid of air filled sacs, this way the plant can constantly float at the surface and lap up sunlight. Other species have adapted to life in rock pools, attaching to rocks, the seaweed s have become able to live in areas of constantly changing temperatures and salt levels.
Animals
Fish
Fish are aquatic vertebrates typically cold blooded and lacking four limbs; they inhabit all areas of the ocean from the surface to the deepest darkest depths. Fish cover a wide array of genus and species but are generally characterised by certain features, they have 2 sets of paired fins and 1 or 2 dorsal fins, scales covering the body, gills and eggs are fertilised externally. There are always however exceptions and variations to the rule, especially as there are about 24,600 known species of fish in the oceans.
Of these 24,600…
- 23,000 are bony fish
- 850 are sharks rays and chimeras
- 85 are hagfish and lampreys
Some fish have even developed adaptations to warm their body temperature even in cold waters, this gives a significant advantage to these species and they seem to be larger hunter species of the family Lamnidae. Other species such as the mudskipper have adapted to survive out side of the ocean and breath air for a period.
Ocean mammals
Ocean mammals are creatures that evolved out of the oceans but since returned to the water. There are 5 groups of marine mammal:
- Order Sirenia: the manatee, dugong.
- Order Carnivora, family Ursidae: the polar bear
- Order Carnivora, infrafamily Pinnipedia: the seal, sea lion, and walrus
- Order Carnivora, family Mustelidae: the Sea Otter and Marine Otter
- Order Cetacea: the whale, dolphin, and porpoise
Ocean mammals have back bones that have developed for movement on land and so tend to move in the water by moving their spines up and down (unlike fish whose spines move side to side) this can restrict manoeuvrability in the water, (this is why ocean mammals have horizontal caudal fins and fish have vertical ones). Ocean mammals also breathe air; they come to the surface take in air and absorb the oxygen during submergence. Ocean mammals are also known to have hair; the amount varies from small wisps of hair on the heads of whales, to the full coats of polar bears and marine otters.
Marine mammals are warm-blooded and are all insulated with a thick layer of blubber that prevents heat loss (with the exception of polar bears and marine otters who rely solely on thick warm coats). These mammals tend to regulate their body temperature higher than the surrounding water to keep warm.
References:
http://www.blueplanetbiomes.org/world_biomes.htm
http://ths.sps.lane.edu/biomes/index1.html
http://www.ucmp.berkeley.edu/exhibits/biomes/index.php
http://www.worldbiomes.com/biomes_aquatic.htm
http://seaweed.ucg.ie/algae/seaweeds.lasso
http://www.cotf.edu/ete/modules/msese/earthsysflr/dforest.html
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