Download
world ecosystems grasslands n.
Skip this Video
Loading SlideShow in 5 Seconds..
World ecosystems: Grasslands PowerPoint Presentation
Download Presentation
World ecosystems: Grasslands

World ecosystems: Grasslands

476 Views Download Presentation
Download Presentation

World ecosystems: Grasslands

- - - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

  1. World ecosystems: Grasslands Dr. Liang-Jun Hu hulj068@gmail.com Faculty of Life Sciences, NENU Apr. 9, 2013

  2. Grasslands Did you know that grasslands are found on every continent except Antarctica?

  3. What Are Grasslands Like? Grasslands are big open spaces. There are not many bushes in the grassland. Trees are found only by rivers and streams. The grassland seems like an endless ocean of grass.

  4. Rainfall Grasslands receive about 10 to 30 inches of rain per year. If they received more rain, the grasslands would become a forest. If they received less, they would become a desert. Grasslands are often located between deserts and forests.

  5. Grassland Soil Grassland soil tends to be deep and fertile. The roots of perennial grasses usually penetrate far into the soil. In North America, the prairies were once inhabited by huge herds of bison and pronghorns who fed on the prairie grasses. These herds are almost gone now, and most of the prairies have been converted into the richest agricultural region on earth. Crops grow well in the rich soil.

  6. Grasslands of the World • Grasslands are found on either side of two desert belts that circle the earth. About one quarter of the earth's land is in the grasslands. • Tropical grasslands -- those closest to the equator -- are hot all year. • Temperate grasslands are farther from the equator -- such as the U.S. prairies -- and have both hot summers and harsh winters.

  7. World Distribution

  8. Temperate grasslands Temperate grasslands once covered much of the interior of North America, and they were common in Eurasia and South America as well. They are highly productive when they are first converted to agricultural uses because the organic material in the soil comes from hundreds of thousands of years of decomposition.

  9. Different Names prairies; pampas; steppes; savannas In North America, the prairies were once inhabited by huge herds of bison and pronghorns, which were hunted by wolves, bears, and other predators. Where U.S. prairies have been converted to farmland, the large herds and predators that followed them are gone now. In addition to the prairies of the U.S. Midwest, the world has other grasslands which go by different names. In South America, grasslands are called "pampas"; in Europe, "steppes"; in Africa, "savannas".

  10. Grassland Type and Distribution in North America

  11. Tall Grass Prairie The Tall Grass Prairie lies mainly in the eastern portion of the Midwest. The grasses here often grow to be five feet tall. The annual rain totals here approach 30 inches. Mixed Grass Prairie  The Mixed Grass Prairie lies mainly in the middle portion of the Midwest. The grasses here often grow to be two and three feet tall. Typically, there are 15 to 25 inches of rain per year. This is the prairie where the buffalo once roamed. Short Grass Prairie The Short Grass Prairie lies mainly in the western portion of the Midwest, hugging the coast of the deserts and the Rocky Mountains into Canada. The grasses here grow to be no more than two feet tall. There is usually little more than ten inches of rain per year in these short grass prairies. Prairie Dogs are common in this area. The Three Types of North American Grasslands In the United States and Canada there are three types of grasslands (or prairies):

  12. Grassland Plants The following pages answer common questions about the prairie and prairie plants.

  13. How do the bees and insects pollinate flowers? This bumble bee is starting the pollination process without even realizing it! When bees land on a flower, like this milkweed flower, their feet often slip into a little groove that holds pollen sacs. When the bee flies away it carries off this sac like a saddlebag stuck on its feet. When this bee lands on another flower looking for nectar, the "saddlebag" falls off, the pollen falls out of the sac, and pollination is underway.

  14. What are some of the most beautiful prairie flowers?-1 The prairie blazingstar is one of the most beautiful flowers on the tallgrass prairie. It has magenta colored flowers arranged along a spike at the top of a long stalk up to 5 feet high. Many kinds of butterflies are attracted to this flower. Sweet coneflower can grow to height of 6 feet if planted in moist soil.

  15. What are some of the most beautiful prairie flowers?-2 The purple coneflower is used by many people in their gardens at home. See how large the orange-colored cone is? This is the part of the flower which produces seeds after the purple petals fall off. Birds like goldfinches love to eat these seeds.

  16. How are prairies maintained? Prairies are maintained by fire and grazing animals. Another way to manage a prairie is to mow it in the middle of July and bale the hay. Haying removes much of the thick vegetation that accumulates, and it allows the prairie to grow in a healthy way.

  17. What is one of the best prairie adaptations? Prairie plants and animals have some neat adaptations, what is one of the best? The monarch butterfly is here pictured with an aster plant. The monarch butterfly and the milkweed plant are interdependent. The larvae of the monarch butterfly feed on milkweed leaves which are toxic to most insects. This toxin (poison) accumulates in the body of the larvae and adult monarch butterfly, making it poisonous to the birds, thus protecting it from being eaten!

  18. Are any prairie plants harmful to people? Sure! This stinging nettle plant is very attractive when it's in flower like this - but be careful! This plant causes a painful sting when it touches your bare skin. It grows to 3 feet tall in moist shady woods. This adaptation helps the plant protect itself from grazers and people, too! Poison ivy is found at the edge of the prairie.

  19. Are there trees on the prairie? I've always thought that there weren't any trees on the prairie - that they were just wide open spaces - is that right? Well, you're partly right... the prairies are full of wide open spaces. However there are many kinds of trees that can be foundin and around a prairie field. These leaves are from a box elder tree, which is a member of the maple family.

  20. Silver Maple TreeRed Bud Tree Pictured to the left are leaves of a silver maple tree. Its seeds fall in late spring and are fun to watch as they float in the air in spiraling motion. Shown to the right are flowers from a red bud tree. This small tree is actually in the pea family! The fruit is shaped like a pea pod, but is flat.

  21. What does a prairie look like when it's not in bloom? Prairies are famous for their beautiful flowers and grasses that bloom in the springtime. In Autumn the prairie takes on a different kind of beauty. Leaves of the tall grasses turn beautiful shades of yellow, orange, and tan.

  22. What is the tallest plant that lives on the prairie? Big bluestem grass is the tallest grass found on tallgrass prairies and it can reach a height of 11 feet! Another name for Big Bluestem is Turkeyfeet because of the shape of the seedheads. This grass was also an important food for the American bison.

  23. What Happened to the American Prairies? About one quarter of the earth's land is grasslands. The wild prairie has disappeared, for the most part, from the United States. Only a few spots of wild prairie remain.  Because the soil is so productive and rich in nutrients, nearly all of the wild grasslands have been converted into commercial farms. Now the prairie feeds the nation and the world. Why do you think prairies are often called the "breadbaskets of the world?"

  24. Grassland Animals Grasslands lack the trees and heavy bush to hide many creatures. Because of the open landscape and the widely spaced trees, grasslands are home to large herds of grazing mammals such as the zebra and bison. Annual rainfall in the grasslands is between 10 to 30 inches, there is a seasonal drought every year. Many animals are active only during the rainy season.

  25. Class: Mammalia: Mammals Diet: Leaves Order: Proboscidea: Elephants Size: body:6 - 7.5 m (19 3/4 - 24 1/2 ft), tail: 1 - 1.3 m (3 1/4 - 4 1/4 in) Family: Elephantidae: Elephants Conservation Status: Vulnerable Scientific Name:Loxodonta africana Habitat: forest, savanna Range: Africa, south of the Sahara African Elephant-1

  26. African Elephant-2 The huge, majestic elephant is perhaps the most imposing of all the African mammals. It has larger ears and tusks than the Asian species and two finger-like extensions at the end of its trunk. Females are smaller than males and have shorter tusks. Elephants rest in the mid-day heat and have one or two periods of rest at night but are otherwise active at any time, roaming with their swinging, unhurried gait in search of food. Depending on its size, an elephant may consume up to 200 kg (440 lb) of plant material a day, all of which is grasped with the trunk and placed in the mouth. The diet includes leaves, shoots, twigs, roots and fruit from many plants, as well as cultivated crops on occasion. 

  27. African Elephant-3 Elephants are social animals, particularly females, and are known to demonstrate concern for others in distress. A troop usually comprises several females and their young of various ages. As they mature, young males form separate troops. Old males may be shunned by the herd when they are displaced by younger males. Breeding occurs at any time of year, and a female in heat may mate with more than one male. The gestation period is about 22 months, and usually only 1 young is born. The female clears a secluded spot for the birth and is assisted by other females. The calf is suckled for at least 2 years and remains with its mother even longer. She may have several calves of different ages under her protection and gives birth only every 2 to 4 years. 

  28. Class: Mammalia: Mammals Diet: Grass Order: Artiodactyla: Even-toed Ungulates Size: body:2.1 - 3.5 m (6 3/4 - 11 1/2 ft), tail: 50 - 60 cm (19 3/4 - 23 1/2 in) Family: Bovidae: Bovids Conservation Status: Non-threatened Scientific Name:Bison bison Habitat: prairie, open woodland Range: N. America  Bison-1

  29. Bison-2 Although there were once millions of bison roaming the North American grasslands, wholesale slaughter by the early European settlers brought them almost to extinction by the beginning of the twentieth century. Since then, due largely to the efforts of the American Bison Society, herds have steadily been built up in reserves, where they live in a semiwild state, and it is estimated that there are now some 20,000 animals.

  30. Bison-3 The male may be as much as 2.9 m (9 1/2 ft) at the shoulders, which are humped and covered with the shaggy, brownish-black fur that also grows thickly on the head, neck and forelegs.  The female looks similar to the male but is smaller; young are more reddish-brown. Both sexes have short, sharp horns. Primarily grazers, bison live in herds that vary from a family group to several thousand; huge numbers formerly made seasonal migrations in search of better pasture. They feed morning and evening. During the day, they rest, chewing the cud or wallowing in mud or dust to rid themselves of parasites. During the mating season, bulls (males) fight for cows (females), which give birth to a single calf, away from the herd, after a gestation of 9 months. Within an hour or two, mother and calf rejoin the herd. The calf is suckled for about a year and remains with its mother until it reaches sexual maturity at about 3 years old. 

  31. What happened to the big herds of prairie animals like bison and antelope? Why don't we see the big herds of prairie animals as much anymore - like bison and antelope?

  32. Bison, Antelope, Deer Well, for one thing, much of the North American prairie land was turned into farms in the early 1900's so that people could make a good living growing and selling crops. Bison, which are often mistakenly called buffalo, were hunted to near extinction because their meat and hides were so valuable. Deer and antelope are still found in places like Wyoming, but the herds are dwindling.

  33. Class: Mammalia: Mammals Diet: Leaves, buds, shoots Order: Perissodactyla: Odd-toed Ungulates Size: body:3 - 3.6 m (9 3/4 - 11 3/4 ft),tail: 60 - 70 cm (23 1/2 - 27 1/2 in) Family: Rhinocerotidae: Rhinoceroses Conservation Status: Vulnerable Scientific Name:Diceros bicornis Habitat: bush country, grassland, woodland Range: Africa: Southern Chad and Sudan to South Africa Black Rhinoceros-1

  34. Black Rhinoceros-2 The black rhinoceros is, in fact, gray in color but varies according to the mud in which it wallows. It has no hump on its neck but has a large head, held horizontally, which bears two horns and sometimes a third small horn. Its upper lip is pointed and mobile, which helps the animal to browse on the leaves, buds, and shoots of small trees and bushes. Less sociable than the square-lipped rhinoceros, black rhinoceroses live alone, except for mothers and young.

  35. Black Rhinoceros-3 Adults live in overlapping home ranges, with boundaries marked by dung heaps. Male and female remain together for only a few days when mating. The female gives birth to a single young after a gestation of about 15 months. The young rhinoceros suckles for about a year and stays with its mother for 2 or 3 years, until her next calf is born.

  36. Class: Mammalia: Mammals  Diet: Small mammals Order: Carnivora: Carnivores  Size: body: 38 - 45 cm (15 - 17 3/4 in), tail: 12.5 - 15 cm (5 - 6 in)  Family: Mustelidae: Mustelids  Conservation Status: Endangered  Scientific Name:Mustela nigripes Habitat: prairie  Range: North America: Alberta to Northern Texas Black-footed Ferret-1

  37. Black-footed Ferret-2 The black-footed ferret feeds mainly on prairie dogs, but these animals are considered farm pests and large numbers are poisoned. This destruction of their natural prey has caused a drastic decline in the numbers of ferrets -- and their indirect poisoning. The black-footed ferret is now protected by law, but it is still in great danger of extinction and its survival depends either on the conservation of prairie dogs or on its ability to adapt to other areas and prey. It is generally a nocturnal animal. In June it produces a yearly litter of 3 to 5 young.

  38. Class: Mammalia: Mammals Diet: Carrion Order: Carnivora: Carnivores Size: body:11.1 - 1.2 m (3 1/2 - 4 ft), tail: 25 - 30 cm (9 3/4 - 11 3/4 in) Family: Hyaenidae: Hyenas Conservation Status: Vulnerable Scientific Name:Hyaena brunnea Habitat: dry savanna, plains, semidesert Range: Africa: Angola to Mozambique, south to Northern South Africa Brown Hyena-1

  39. Brown Hyena-2 Typical of its family, with a bulky head and back sloping toward the rear, the brown hyena has long, rough hair over much of its body, with a mane of even longer hair on the neck and shoulders. This hyena is usually dark brown to brownish-black in color, with a lighter-brown mane and legs. Unless in a family group, the brown hyena is solitary, but it sometimes gathers with others in a hunting pack or at a big carcass. It lives in a large territory, which it marks with secretions from anal scent glands and with feces. During the day, the brown hyena sleeps among rocks or tall grass. Otherwise, it may find a burrow, often one left by another animal, such as an aardvark.

  40. Brown Hyena-3 It emerges at night to find carrion or to hunt prey such as rodents, birds, including poultry, reptiles or wounded large animals. Near the coast, brown hyenas also feed on dead fish, mussels and the stranded corpses of seals and whales. A litter of 2 to 4 young is born in a burrow after a gestation of 92 to 98 days. The young are suckled for about 3 months but remain with their parents for up to 18 months, during which the male brings them food. Although protected in game reserves, brown hyenas are considered pests because of their habit of attacking livestock, and large numbers have been killed by farmers. 

  41. Class: Mammalia: Mammals Diet: Leaves, buds, fruits Order: Artiodactyla: Even-toed Ungulates Size: body:3 - 4 m (9 3/4 - 13 ft), tail: 90 cm - 1.1 m (35 1/2 in - 3 1/2 ft) Family: Giraffidae: Giraffes Conservation Status: Non-threatened Scientific Name:Giraffa camelopardalis  Habitat: savanna Range: Africa, south of the Sahara Giraffe-1

  42. Giraffe-2 The giraffe, with its long legs and its amazingly long neck, when erect stands up to 3.3 m (11 ft) at the shoulder and nearly 6 m (19 1/2 ft) at the crown. Its characteristic coloration of a light body and irregular dark spots is very variable, both geographically and between individuals; some animals may be almost white or black, or even unspotted. Both male and female have skin-covered horns, one pair on the forehead and sometimes a smaller pair farther back, on the crown. Some animals have yet another small horn, or bump, between these pairs. The tail ends in a tuft of long hairs.

  43. Giraffe-3 Gregarious animals, giraffes usually live in troops of up to 6, sometimes 12, and may occasionally gather in larger herds. A troop consists of females and their offspring, led by a male. Males fight for possession of females, wrestling with their heads and necks. The troop ambles around its territory, feeding mostly in the early morning and afternoon on the foliage, buds, and fruits on the top of acacia and thorn trees. The giraffes may also eat grass, other plants, and grain crops. At midday, giraffes rest in shade and at night lie down for a couple of hours or rest standing. Females give birth to a single offspring, rarely twins, after a gestation of over a year -- usually 400 to 468 days. Births invariably occur at first light. The young is suckled for 6 to 12 months and continues to grow for 10 years. 

  44. Class: Aves: Birds Diet: Plants Order: Galliformes: Gamebirds Size: body:42 - 46 cm (16 1/2 - 18 in) Family: Tetraonianae: Grouse Conservation Status: Non-threatened Scientific Name:Tympamuchus cupido Habitat: prairie Range: Central North America  Greater Prairie Chicken-1

  45. Greater Prairie Chicken-2 This increasingly rare bird was once common over a large area of North America. Male and female birds look similar, but females have barred tail feathers and smaller neck sacs. Prairie chickens feed on plant matter, such as leaves, fruit and grain, and in the summer they catch insects, particularly grasshoppers. Male birds perform spectacular courtship displays, inflating their orange neck feathers. They give booming calls and stamp their feet as they posture, to make the display even more impressive. Female birds lay 10 to 12 eggs and incubate them for 21 to 28 days.

  46. Class: Mammalia: Mammals Diet: Large mammals, also smaller mammals, birds Order: Carnivora: Carnivores Size: body:1.4 - 2 m (4 1/2 - 6 1/2 ft), tail: 67 cm - 1 m (26 1/4 in - 3 1/4 ft) Family: Felidae: Cats Conservation Status: Non-threatened Scientific Name:Panthera leo Habitat: open savanna Range: Africa, south of the Sahara; Northwest India; formerly more widespread in Asia Lion-1

  47. Lion-2 A splendid, powerfully built cat, the lion has a broad head, thick, strong legs and a long tail tipped with a tuft of hair that conceals a clawlike spine. The male is larger than the female and has a heavy mane on the neck and shoulders.  Body coloration varies from tawny-yellow to reddish-brown, and the mane may be light yellow to black. They live in groups, known as prides, consisting of up to 3 adult males and up to 15 females and their young in a territory that is defended against intruders, particularly other mature male lions. A small group of young males without prides may live together. 

  48. Lion-3 This impressive creature actually spends 20 or more hours a day resting. Lions normally hunt during the day, but in areas where they themselves are hunted, they are active only at night. Lions prey on mammals, such as gazelles, antelope and zebras, and may cooperate to kill larger animals, such as buffaloes and giraffes. Smaller animals and birds and even crocodiles may also be eaten. Lionesses do most of the hunting, often in groups, some acting as beaters to drive prey toward other lionesses lying in wait. Lions attack by stalking their prey and approaching it as closely as possible before making a short, rapid chase and pounce.  They kill by a bite to the neck or throat.

  49. Lion-4 Breeding occurs at any time of year. A litter of 1 to 6 young, usually 2 or 3, is born after a gestation of 102 to 113 days. They are suckled for about 6 months, but after the first 3 months, an increasing proportion of their food comes from the kills of adults. The cubs are left behind with one or two adults while the rest of the pride goes off to hunt, but if a kill is made, a lioness will return and lead them to it. Once they are over 4 months old, the cubs accompany their mothers everywhere, even following behind on hunting trips. They are not sexually mature until about 18 months old; young males are driven from the pride at about this age, but females remain with their family. 

  50. Class: Aves: Birds  Diet: Plants Order: Struthioniformes: Ostriches Size: body:1.75 - 2.75 m (6 - 9 ft) tall Family: Struthionidae: Ostrich Conservation Status: Non-threatened Scientific Name:Struthio camelus Habitat: grassland, arid land Range: Africa: Parts of Central and Southern Africa Ostrich-1