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Savanna PowerPoint Presentation

Savanna

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Savanna

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  1. Savanna • The savanna is an area of tropical, wooded grassland found in the drier regions of tropical wet and dry climate, an intermediate stage between open grassland and forest. Widely scattered, short, flat-topped trees dot the landscape. The grass is tall and grows in bunches. Grass is different from other green plants. In most plants, the zones of growth of new plant tissue are at the tips of leaves, shoots, and roots. In grass, new tissue grows from the base of the leaves. When animals eat the top portion of the grass plant, they do not stop it from growing. Underground runners allow grass to spread over a wide area, and a fibrous mat of roots enables grass to withstand drought and fire. Grasses are pollinated by the wind; they are not dependent upon insects that might not be able to withstand long periods of drought. New grass grows at the start of each rainy season but soon withers and dies during the dry period. Fire plays an important role in removing dead material so new plants can grow. 

  2. Montane • The vegetation that grows on a mountain is very different from that of the surrounding lowlands. Tall mountains intercept the movement of clouds, forcing rain to fall on their slopes. At the base of the mountain, tall trees form an open canopy forest; the trees are able to grow here because there is enough water and it is not too cold. The plant communities change in response to the cooler temperatures at higher elevations. Vegetation gets shorter; the montane rain forest gives way to bamboo forest and then open grassland with smaller trees and shrubs. Leaves are smaller and the trunks of trees are twisted. As the air gets colder, short grasses, mosses, lichens, and other plants replace the shrubs. Beyond a certain elevation it is too cold for any plants, except for hardy lichens, to grow at all. 

  3. Chaparral • Story Card 1- hot and dry most of the year- short, cold rainy winters- plants and shrubs scattered about- fires burn often in summer and fall- plants and animals survive on little waterSpecial Features of your Mammal:- herbivorous- small mammal- good sense of hearingThings to think about:- Can your mammal dig deep? Jump far? Run fast?- What does your mammal eat? How does it get its food?- What color or colors is your mammal?- How does your mammal escape predators?

  4. TUNDRA • Story Card 2- cold and snowy most of the year- rocky, frozen soil- short summer when some plants grow- some animals visit during migrationSpecial Features of your Mammal:- omnivorous- survives in cold temperatures- can walk and swimThings to think about:- How does your mammal protect itself?- What does your mammal eat? How does it get its food?- How does your mammal stay warm?- What color or colors is your mammal?- What kind of legs, feet, flippers or toes does it have?

  5. Rainforest • Story Card 3- soft and squishy soil- hot, with lots of rain- home to many different animals- thick plant life all year long- many tall treesSpecial Features of your Mammal:- active at night, or nocturnal- carnivorous- has 4 legsThings to think about:- Can your mammal climb? Jump far? Run fast?- What does your mammal eat? How does it get its food?- What senses would your mammal use at night?- What color or colors is your mammal?

  6. Desert Scrub • Many plants are able to survive in a desert; indeed, very few areas on Earth have no life at all. Desert plants have adaptations to live in the heat with little water. They are short and grow far apart from each other, so the roots of each plant can collect and store water. Many bushes grow and flower rapidly after a rain shower. Some plants are deciduous during the dry season; others have leaves that remain but are adapted to minimize loss of water. Plants called succulents, which have thick bark, swollen stems, and fat leaves to store water, do well in this harsh environment. Other plants have spines (modified leaves) and green stems to manufacture nutrients. Oases occur where underground water comes close to the ground surface. The vegetation is more lush here, and oases are very attractive to wildlife. 

  7. Tropical Rain Forest • tAbundant sunlight, water, and warm temperatures encourage many different kinds of trees to grow in a rain forest. Trees are tall (150 to 200 feet, 31 to 46 meters) and straight and grow close together, forming an unbroken canopy overhead. A few very tall trees emerge from the canopy. The smooth tree trunks have no lower branches; most of their leaves and flowers grow near the top in the sunlight. The tree roots are shallow as they do not have to go deep to reach water or nutrients. The trunks of the trees are buttressed for support in the absence of deep roots, and garlands of vines and air plants cling to the trees. The trees are broadleaf (the leaves are broad, flat, and thin) and evergreen, as there is relatively little change in the seasons. Many of the leaves have pointed tips to shed water. Due to the lack of light, only a few short trees (25 to 50 feet high, 7.5 to 15 meters) grow below in the shade of the canopy.  It is always semi-dark on the floor of a rain forest. Unlike the familiar jungle of the movies, there is little or no underbrush, except in areas where sunlight can reach, such as along a river or in a clearing created by a fallen tree. Few green plants grow in the gloom of the forest floor. Fungi, which do not need sunlight, grow well here, and quickly decompose fallen leaves. Much of the animal activity occurs high in the treetops. 

  8. Deciduous Forest This plant community is found in wetter areas of tropical wet and dry climate. While there is enough rain for trees to grow, the long dry season forces the trees to lose their leaves (these are called deciduous trees), unlike the trees in the rain forest. The plants drop their leaves, not because it is too cold, but because there is not enough water; the plants become dormant until rain falls and they can grow again. Trees of a tropical deciduous forest and scrub do not grow close together (this is known as an open canopy). The trees are shorter and farther apart as their roots spread out in search of water. Sunlight reaches the forest floor, which encourages an undergrowth of bushes to thrive. In areas that receive less rainfall, there is not enough water for trees to grow, and scrub (shrubs and stunted trees) replaces the forest. During the dry season, fires are not uncommon. The scrub plants have adaptations to survive a drier climate - thick bark; small, fat, evergreen leaves that store water; and protective thorns. This community represents a gradual change from the tropical rain forest to the savanna.