Download Tropical Rainforest Rainforests are very dense, warm, wet forests

Tropical Rainforest
Rainforests are very dense, warm, wet forests. They are havens for millions of plants and animals.
Rainforests are extremely important in the ecology of the Earth. The plants of the rainforest generate
much of the Earth's oxygen. These plants are also very important to people in other ways; many are used
in new drugs that fight disease and illness.
Where are Rainforests? Tropical rainforests are located in a band around the equator, mostly in the area
between the Tropic of Cancer (23.5° N latitude) and the Tropic of Capricorn (23.5° S latitude). This
3,000 mile (4800 km) wide band is called the "tropics." Tropical rainforests are found in South America,
West Africa, Australia, southern India, and Southeast Asia. Go to a rainforest map printout to color.
Strata of the Rainforest
Different animals and plants live in different parts of the rainforest. Scientists divide the rainforest into
strata (zones) based on the living environment. Starting at the top, the strata are:
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EMERGENTS: Giant trees that are much higher than the average canopy height. It houses many
birds and insects.
CANOPY: The upper parts of the trees. This leafy environment is full of life in a tropical
rainforest and includes: insects, birds, reptiles, mammals, and more.
UNDERSTORY: A dark, cool environment under the leaves but over the ground.
FOREST FLOOR: Teeming with animal life, especially insects. The largest animals in the
rainforest generally live here.
Animals that Live in Rainforests: Ridiculously huge numbers of animals live in rainforests, including
microscopic animals, invertebrates (like insects and worms), fish, reptiles, amphibians, birds, and
mammals. The different rainforests of the world support different populations of animals. A few animals
from each rainforest are listed below:
Temperate Rain Forest
For temperate rain forests of North America, Alaback's definition[1] is widely recognized:[2]
1. Annual precipitation 200–400 cm
2. Mean annual temperature between 4oC and 12oC. (39o and 54oFahrenheit)
However, required annual precipitation depends on factors such as distribution of rainfall over the year,
temperatures over the year and fog presence, and definitions in other countries differ considerably. For
example, Australian definitions are ecological-structural rather than climatic:
1. Closed canopy of trees excludes at least 70% of the sky
2. Forest is composed mainly of tree species which do not require fire for regeneration, but with
seedlings able to regenerate under shade and in natural openings[3]
The latter would, for example, exclude a part of the temperate rain forests of western North America , as
Coast Douglas-fir, one of its dominant tree species, requires stand-destroying disturbance to initiate a
new cohort of seedlings.[4] The North American definition would in turn exclude a part of temperate rain
forests in other countries.
The wildlife of the temperate rainforest ranges from beavers and raccoons to cougars and black bears.
But the elk may be the most important animal of all. The elk are called the "landscape gardeners" of the
Olympic National Forest. Their foraging and trampling provide the balance that is necessary. If the elk
were not there, the rainforest would become a thicket. The elk were once hunted and became
endangered. Now the herd is now steady and the forest is well balanced again.
Desert
Deserts cover about one fifth (20 percent) of the earth's land area. The desert is a harsh environment
with very little rainfall and extreme temperatures; a desert is defined as a region that gets less than ten
inches of precipitation per year. Because of these dry conditions, there is limited plant and animal life in
deserts. Desert plants (like cacti) are not abundant; neither is animal life.
Some deserts get both very hot (during the day) and very cold (during the night, when temperatures can
drop well below freezing). Some deserts, however, are always cold (for example, the Gobi Desert in
Asia, and the desert on the continent of Antarctica).
Different animals live in the different types of deserts. Animals that live in the desert have adaptations to
cope with the lack of water, the extreme temperatures, and the shortage of food. To avoid daytime heat,
many desert animals are nocturnal; they burrow beneath the surface or hide in the shade during the day,
emerging at night to eat. Many desert animals do not have to drink at all; they get all the water they need
from their food. Most desert animals are small.
Desert Extremes: The biggest desert is northern Africa's Sahara Desert; it covers roughly 3,500,000
square miles (9,065,000 square kilometers). The driest deserts are the Atacama Desert of northern Chile,
South America, and the Lut Desert in eastern Iran; these extreme deserts get less than half an inch (about
1 centimeter) of precipitation each year - and it is from condensed fog, and not from rain.
Animals include spiders, rattlesnakes, lizards, coyotes, rats, scorpions, cobras, jackals, moles, eagles,
hawks, camels, vultures, and kangaroos.
Savanna/Grasslands
What is a Savanna? A savanna is a hot, seasonally dry grassland with scattered trees. This environment
is intermediate between grassland and a forest. Savannas are located in the dry tropics and the
subtropics, often bordering a rainforest. Savannas have an extended dry season and a rainy season.
Animal Adaptations: The animals that live in savannas have adapted to a great deal of variability in the
food supply throughout the year; there are times of plenty (during and after the wet season) and times of
almost no food or water (during the dry season). Many savanna animals migrate to deal with this
problem.
Where are Savannas? Savannas are located in Africa, Madagascar (an island off the east coast of
Africa), Australia, South America, India, and the Myanmar-Thailand region of Southeast Asia.
Animals that Live in Savannas: Many animals live in savannas, from invertebrates (like grasshoppers,
termites, and beetles) to large mammals (like lions and leopards). The different savannas of the world
support different populations of animals.
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Africa - aardvark, African elephant, African wild cat, antelopes, buffalo, Cape hunting dog,
caracal, cheetah, eland, gerenuk, giraffe, gnu, Grant's gazelle, hippopotamus, hyena, impala,
jackal, kudu, leopard, lion, meerkat, oryx, ostrich, red-billed oxpecker, rhinoceros, serval,
waterbuck, vulture, zebra, purple-crested louries, grey louries, green pigeons, raptors, hornbills,
shrikes, flycatchers, rollers
Australia - kangaroo, wallaby, pigeon, dove, parrot, finch, wombat
South America - rodents (like the capybara), rhea, and deer.
India - Asiatic water buffalo, Asian elephant, Indian rhinoceros, Indian wolf, tiger, savanna
nightjar
Myanmar-Thailand - Asian elephant, Asiatic Water buffalo, pygmy hog, tiger
Deciduous Forest
Deciduous forests are forests in cool, rainy areas; they have trees that lose their leaves in fall and regrow
them in spring. Deciduous forests are found in the middle latitudes around the globe and have four
distinct seasons: spring, summer, fall, and winter. In the Northern Hemisphere, these forests are found
in North America, Europe, and Asia. In the Southern Hemisphere, there are smaller areas of these
forests, in South America, Africa, and Australia. The growing season in these forests is about 6 months
long.
Temperature and Precipitation: The average summer temperature in deciduous forests is roughly 7590°F (24-34°C) but gets as high as 100°F (50°C), depending on the altitude of the forest. Forests higher
in the mountains are colder. Deciduous forests receive from 2 to 5 feet (0.5-1.5 m) of precipitation (both
rain and snow) each year. Humidity in these forests is high, from 60% to 80%.
Fall Colors: In the fall, the number of hours of daylight decreases. This causes some plants and trees
(called deciduous) to stop producing chlorophyll (a green pigment that converts sunlight into chemical
energy) and eventually lose their leaves. During this time, these leaves turn brilliant colors, ranging from
red to orange to yellow to brown.
Soil: The soil in the deciduous forests is quite fertile, since it is often enriched with falling leaves, twigs,
logs, and dead organisms.
Layers of the Deciduous Forest: There are five layers (also called zones or strata) in the temperate
deciduous forest. These include the:
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Tree stratum, the tallest layer, 60 -100 feet high, with large oak, maple, beech, chestnut, hickory,
elm, basswood, linden, walnut, or sweet gum trees.
Small tree or sapling layer - short tree species and young trees.
Shrub layer - shrubs like rhododendrons, azaleas, mountain laurels, and huckleberries.
Herb layer - short plants.
Ground layer - lichens, clubmosses, and true mosses.
Some animals found here include rabbits, deer, bears, opossums, raccoons, birds, ducks, squirrels,
skunks, and porcupines.
Boreal Forest (Taiga/Coniferous)
A taiga, also called a boreal forest or northern coniferous forest, is a cold woodland or forest. This
biome spans the northern parts of North America, Europe, and Asia. Taigas are generally located south
of tundras and north of temperate deciduous forests and temperate grasslands. The taiga is the largest
land biome on Earth, covering about 50 million acres of land (20 million hectares); this is about 17% of
the Earth's land area. Taiga is a Russian word for marshy pine forest.
The taiga is characterized by a cold, harsh climate, a low rate of precipitation (snow and rain), and short
growing season. There are two types of taigas: open woodlands with widely spaced trees, and dense
forests whose floor is generally in shade.
Taigas are relatively low in animal diversity because of the harsh winters. Some taiga animals are able to
cope with the cold winter environment, but many migrate south to warmer climates during the winter
and others go into hibernation.
Some animals found here include bears, caribou, moose, badgers, arctic types of foxes, hares, and
wolves, deer, huskies, ox, certain birds, reindeer, owls, weasels.
Tundra
The tundra is a cold, treeless area; it is the coldest biome. The tundra is characterized by very low
temperatures, very little precipitation (rain or snow), a short growing season, few nutrients, and low
biological diversity. The word tundra comes from the Finnish word tunturia, which means "treeless
plain."
There are two types of tundras, Arctic tundras and alpine tundras.
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Arctic tundras are frozen, windy, desert-like plains in the Arctic that are dotted with bogs and
ponds. Permafrost (a layer of frozen subsoil) covers the ground, so there is very little drainage of
water. The short growing season lasts for only 50 to 60 days. Arctic tundras are located in the far
north of Greenland, Alaska, Canada, Europe, and Russia. Some animals of the Arctic tundra
include:
o Mammals - Arctic foxes, Arctic hares, caribou, ermine, lemmings, musk oxen, polar
bears, porcupines, Arctic shrews, squirrels, voles, weasels, wolves
o Birds - Arctic loons, snowy owls, falcons, ptarmigans, ravens, snow buntings, snow
birds, snow geese, sandpipers, Arctic terns, tundra swans, many species of gulls
o Fish - cod, flatfish, salmon, trout
o Insects - Arctic bumblebees, blackflies, flies, grasshoppers, mosquitoes, and moths.
Alpine tundras are located high in mountains worldwide, above the tree line. The growing season
is about 180 days, and nighttime temperatures are usually below freezing. The soil is welldrained (unlike the Arctic tundra). Some animals of the alpine tundra include:
o Mammals - elk, marmots, mountain goats, pikas, sheep
o Birds - grouse-like birds
o Insects - beetles, butterflies, grasshoppers, and springtails.
Intertidal Zone
The intertidal area (also called the littoral zone) is where the land and sea meet, between the high and
low tide zones. This complex marine ecosystem is found along coastlines worldwide. It is rich in
nutrients and oxygen and is home to a variety of organisms.
An Inhospitable, Changing Environment:
Much of this inhospitable environment is washed by the tides each day, so organisms that live here are
adapted to huge daily changes in moisture, temperature, turbulence (from the water), and salinity.
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Moisture: The littoral zone is covered with salt water at high tides, and it is exposed to the air at
low tides; the height of the tide exposes more or less land to this daily tide cycle. Organisms
must be adapted to both very wet and very dry conditions.
Water Movement: The turbulence of the water is another reason that this area can be very
difficult one in which to survive - the rough waves can dislodge or carry away poorly-adapted
organisms. Many intertidal animals burrow into the sand (like clams), live under rocks, or attach
themselves to rocks (like barnacles and mussels).
Temperature: The temperature ranges from the moderate temperature of the water to air
temperatures that vary from below freezing to scorching.
Salinity: Depressions on the shores sometimes form tide pools, areas that remain wet, although
they are not long-lasting features. The salinity of tide pools varies from the salinity of the sea to
much less salty, when rainwater or runoff dilutes it. Animals must adapt their systems to these
variations. Some fish, like sculpin and blennies, live in tide pools.
Predators:
Animals that live in the littoral zone have a wide variety of predators that eat them. When the tide is in,
littoral organisms are preyed upon by sea animals (like fish). When the tide is out, they are preyed upon
by land animals, like foxes and people. Birds (like gulls) and marine mammals (like walruses) also prey
on intertidal organisms extensively.
Neritic Zone
The uppermost layer of the world's oceans is bathed in sunlight during the daytime. This bright ocean
layer is called the sunlit zone or the euphotic zone (euphotic means "well lit" in Greek) or the epipelagic
zone (epipelagic means "upon the sea"). The depth of this zone depends on the clarity or murkiness of
the water. In clear water, the euphotic zone can be quite deep; in murky water, it can be only 50 feet
deep. On average, it extends to about 660 feet (200 meters); the depth of the ocean averages about
13,000 feet or 4,000 m. The temperature in this zone ranges from 104 to 27 degrees F.
In this zone, there is enough light for photosynthesis to take place, so many plants and other
photosynthetic organisms live in this zone and food is abundant. Photosynthesis is a process in which
sunlight and carbon dioxide gas are converted into food (chemical energy contained in carbohydrates)
and oxygen gas. Photosynthesis in the oceans creates approximately 90% of the Earth's gaseous oxygen.
Most of the oxygen is produced by phytoplankton. These primary producers (also called autotrophs) are
the first link in the food chain in the oceans. Because of this food source, many animals also live in this
zone. In fact, most of the life in the ocean is found in this zone, although it is the smallest ocean zone in
terms of volume of water.
Primary Producers (Algae, Phytoplankton, and Plants): In the euphotic zone, photo synthesizers
(autotrophs) include:
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Free-floating algae -- often called seaweed
o Red algae ( Rhodophyta) -- Porphyra (from which edible nori is made), dulse, Ceramium
and maerl
o Green algae (Chlorophyta) --thongweed, sea lettuce (Ulva)
o Brown algae (Phaeophyta) -- like fast-growing kelp, Sargassum, Turbinaria, Dictyota,
and wrack
Phytoplankton -- tiny, one-celled photosynthetic plankton like diatoms, dinoflagellates, and
coccolithophorids
Plants
o Flowering plants (angiosperms)
 Submerged: Sea grasses -- flowering plants like eelgrass and thalassia
 Not Entirely Submerged: Mangroves -- trees that root in the shallow seafloor but
grow above water.
Animals: Examples of euphotic zone animals include most ocean fish (including sharks and rays), mano'-war, jellyfish, sea turtles, seals, coral, and zooplankton. Some bottom-dwellers live in the euphotic
zone - this zone is defined in terms of light, not depth.
Some of the animals in this zone have counter shading. Counter shading is when an animal is light on its
underside and dark on its upper parts. When a predator looks down at a counter shaded animal, it blends
into the darker waters; when a predator looks at a counter shaded animal from below, the light
underbelly disappears into the light. This adaptation helps camouflage the organism, hiding it from
predators and allowing it to sneak up on prey. Most sharks, for example, are counter shaded.
Open Ocean – deep zone
The middle layer of the world's oceans receives only faint, filtered sunlight during the daytime. This is
because the seawater absorbs the sunlight. This barely-lit ocean layer is called the twilight zone or the
disphotic zone (disphotic means "poorly lit" in Greek) or the mesopelagic zone (mesopelagic means
"middle sea"). This zone appears deep blue to black in color. The depth of this zone depends on the
clarity or murkiness of the water. In clear water, the disphotic zone can begin at depths up to 600 feet; in
murky water, it can start at only 50 feet deep. It is usually begins somewhere between these two
extremes. The disphotic zone extends to about 3,300 feet (about 1,000 m) deep (this is where the aphotic
zone begins). On average, this zone extends from 660 to 3,300 feet (200 to 1,000 m).
In the disphotic zone, there is enough light to see during the day, but not enough light for photosynthesis
to take place, so no plants live in this zone. The amount of light decreases with depth. Because of this,
food is not abundant. The water in the disphotic zone is cold (the temperature ranges from 41 to 39
degrees F) and decreases with depth. The pressure is high -- it can be up to 1,470 psi (pounds per square
inch) and increases with depth. The amount of dissolved oxygen in the water is less than in the sunlit
zone.
The animals that live in the disphotic zone are adapted to life in near darkness, cold water and high
pressure. Many of the animals in this zone have large eyes, helping them see in the nearly dark waters.
Most are small, dark and thin (to help camouflage them). Many have large teeth and jaws.
Bioluminescence: Many of the animals in the disphotic zone are bioluminescent; they can make their
own light. Some bioluminescent animals have special organs that produce light by a chemical reaction;
other bioluminescent animals have glowing bacteria that live on them. Most bioluminescent organs
called photophores give off an eerie blue-green light. A rare exception is the Malacosteidae or Loosejaw
fish, which produce a red light for intraspecies communication (red is invisible to most other deep-sea
marine organisms, which see mainly blues and greens). Animals use their light to help them find food, to
help them find mates, and/or to confuse predators (they do this by camouflaging themselves or
distracting predators).
Diet: Animals in this zone feed on plant matter and algae that fall into this zone from the euphotic zone
(the well-lit zone above the disphotic zone), animals that stray into this twilight zone, and each other.
Animals in the disphotic zone are filter feeders, grazers, and predators. Some animals migrate vertically
(up and down) in order to feed upon the abundant life in the bright zone above them. Most of the
animals that eat other animals in this zone do not chase their prey; they lure the prey to them or simply
wait for the prey to come to them. Some predators lure their prey with bioluminescent barbels (fleshy
projections near the mouth) that look like small animals.
Examples of disphotic zone animals include algae, coelacanths, copepods, crabs and other crustaceans,
ctenophores, dinoflagellates, dragonfish, fangtooth, gulper eel, hatchet fish, hydrozoans, medusas,
lantern fish, snipe eels, some octopuses, mid-water jellyfish (Cnidarians), plankton, polychaetes,
radiolarians, siphonophore, rattalk fish, sea dragons, some shrimp, some squid, viperfish and many
worms (including tubeworms and segmented worms).
Estuary
An estuary is a partially enclosed body of water formed where freshwater from rivers and streams flows
into the ocean, mixing with the salty sea water. Estuaries and the lands surrounding them are places of
transition from land to sea, and from fresh to salt water. Although influenced by the tides, estuaries are
protected from the full force of ocean waves, winds, and storms by the reefs, barrier islands, or fingers
of land, mud, or sand that define an estuary's seaward boundary.
Estuaries come in all shapes and sizes and go by many different names, often known as bays, lagoons,
harbors, inlets, or sounds. (Note not all water bodies by those names are necessarily estuaries. The
defining feature of an estuary is the mixing of fresh and salt water, not the name.) Some familiar
examples of estuaries include San Francisco Bay, Puget Sound, Chesapeake Bay, Boston Harbor, and
Tampa Bay.
The tidal, sheltered waters of estuaries support unique communities of plants and animals, specially
adapted for life at the margin of the sea. Estuarine environments are among the most productive on
earth, creating more organic matter each year than comparably-sized areas of forest, grassland, or
agricultural land (1). Many different habitat types are found in and around estuaries, including shallow
open waters, freshwater and salt marshes, sandy beaches, mud and sand flats, rocky shores, oyster reefs,
mangrove forests, river deltas, tidal pools, sea grass and kelp beds, and wooded swamps.
The productivity and variety of estuarine habitats foster a wonderful abundance and diversity of wildlife.
Shore birds, fish, crabs and lobsters, marine mammals, clams and other shellfish, marine worms, sea
birds, and reptiles are just some of the animals that make their homes in and around estuaries. These
animals are linked to one another and to an assortment of specialized plants and microscopic organisms
through complex food webs and other interactions.
Estuaries are places where rivers meet the sea. They are fascinating and beautiful ecosystems distinct
from all other places on earth.