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=**Our powerpoint is now available at the multiply website**= (Yeah, I put many, many other places where you can download there)

Royce Chua H1D - Leader Sigmund Ty H1B Carlo Tiu H1C

=__**Definition**__= Biomes are like the world's major "communities". These "communities" are classified according to the plants and animals that are commonly found there and characterized by the adaptations of organisms to that specific "community".

=__**Major Biomes**__=

There are a total of six major biomes. These are:
 * Freshwater
 * Marine
 * Rain forest
 * Desert
 * Grassland
 * Tundra

**__Freshwater Biome__**
Freshwater means water that has a low concentration of salt in it, usually around 1%. The plants and animals have adjusted to this concentration and would not live in water with very different concentration levels due to the hypertonic and hypotonic solutions. There are different types of freshwater regions:


 * Ponds and Lakes
 * Streams and Rivers
 * Wetlands

__**Ponds and Lakes**__
Ponds and lakes have limited diversity in terms of the plants and animals living in it because they do not have an opening to rivers, seas, etc., making the other fish from outside the lake not able to get in. Most of the animals living in the ponds and lakes are so small that you need a microscope to view them. Microbes such as bacteria and protists are also present in lakes and ponds due to their role in decomposition and nutrient recycling.

Lakes and ponds are divided into three different “zones” which are usually determined by depth and distance from the shoreline.

The topmost zone near the shore of a lake or pond is the //__littoral zone__//. This zone is the warmest since it is shallow and therefore, more exposed to the Sun's heat.Turtles, snakes, and ducks are also found here. The animals here are mainly the food for the other animals in the other zones. The near-surface open water surrounded by the littoral zone is the //__limnetic__ zone//. The limnetic zone is well-lighted (like the littoral zone) since it is also exposed to the Sun and is dominated by plankton. A variety of freshwater fish also occupy this zone.

The deep part of the lake/pond is the //__profundal__ zone//. This zone is much colder than the other two this is because little light penetrates all the way through the limnetic zone into the profundal zone. This zone is also much denser because of the colder temperature. The animals eat the dead organisms that falls from the upper zones like the plankton and use oxygen for cellular respiration.

Temperature varies in ponds and lakes seasonally. In between the two layers, there is a narrow zone called the __thermocline__ where the temperature of the water changes rapidly. During the spring and fall seasons, there is a mixing of the top and bottom layers, usually due to winds, which results in a uniform water temperature. This mixing also circulates oxygen throughout the lake, giving the animals in the profundal zone oxygen to breathe.

__**Streams and Rivers**__[[image:River.jpg width="294" height="256" align="left" caption="South Island River"]]
These are bodies of flowing water flowing in one direction. Streams and rivers can be found almost everywhere - they start at headwaters, which may be springs, melted snow or even lakes, and then travel all the way to their mouths, which is usually the ocean or bays.

The characteristics of a river or stream change during the journey from the source to the mouth. The temperature is cooler at the source than it is at the mouth. The water has higher oxygen levels, and freshwater fish such as trout can be found there. Towards the middle part of the stream/river, the width increases and the species diversifies. The water is also clearer at the start because toward the mouth of the river/stream, the water becomes murky from all the sediments that it has picked up upstream, decreasing the amount of light that can penetrate through the water. Since there is less light, there is less plants. Since there is less plants, there is less oxygen in the water. And because of the lower oxygen levels, mostly only fish that require less oxygen is found.

__**Wetlands**__[[image:Shorelinewetland-Minnesota.JPG width="445" height="256" align="right" caption="An example of a Wetland"]]
Wetlands are areas of standing water that support aquatic plants. Marshes, swamps, and bogs are all considered wetlands.

Wetlands have the highest species diversity of all ecosystems. Wetlands are not wholly considered freshwater ecosystems as there are some that have high salt concentrations — these support different species of animals, such as shrimp, shellfish, and various grasses.

__**Marine**__
Marine regions cover about three-fourths of the Earth's surface. Marine algae give most of this biome's oxygen supply and also takes in most of the carbon dioxide in it.
 * Oceans
 * Coral reefs
 * Estuaries

The largest of all the ecosystems, oceans are very large bodies of water that covers up most of the Earth's surface. Like ponds and lakes, the ocean regions are separated into separate zones: __intertidal, pelagic, benthic, and abyssal__. All four zones have a great diversity of species.

The //__intertidal__ zone// is where the ocean meets the land — sometimes it is submerged and at other times exposed, as waves and tides come in and out. In those areas usually submerged during high tide, there is a more diverse array of algae and small animals and fishes. At the bottom of the intertidal zone, which is only exposed during the lowest tides, many invertebrates, fishes, and seaweed can be found. The //__pelagic__ zone// includes those waters further from the land, basically the open ocean. The pelagic zone is generally cold though, just like ponds and lakes. The flora in the pelagic zone include surface seaweeds. The fauna include many species of fish and some mammals, such as whales and dolphins. Many feed on the abundant plankton.

The //__benthic__ zone// is the area below the pelagic zone, but does not include the very deepest parts of the ocean. The bottom of the zone consists of sand, slit, and/or dead organisms. Here temperature decreases as depth increases toward the abyssal zone, since light and heat cannot reach through the deeper water. Flora are represented primarily by seaweed while there are many fauna due to the nutrient-rich environment

The deep ocean is the //__abyssal__ zone//. The water in this region is very cold, highly pressured, high in oxygen content, but low in nutritional content. The abyssal zone supports many species of invertebrates and fishes. Mid-ocean ridges, often with hydrothermal vents, are found in the abyssal zones along the ocean floors.

[[image:coral_reef_florida.jpg width="424" height="286" align="left"]]__**Coral Reefs**__
Coral reefs are widely distributed in warm shallow waters. Naturally, the dominant organisms in coral reefs are corals. Besides corals, the fauna include several species of microorganisms, invertebrates, fishes, sea urchins, octopuses, and sea stars.

__**Estuaries**__
Estuaries are areas where freshwater streams or rivers merge with the ocean. This is similar to the "mouths" of rivers and streams. This mixing of waters with such different salt concentrations creates a very interesting and unique ecosystem. A result of this ecosystem is that there are many diverse plant and animal life here.

There may seem to be no life in estuaries at first glance, but there are actually a lot. Most animals that live here are small. Some of the animals that live in estuaries are:
 * Mud Worms
 * Crabs
 * Cockles
 * Seagulls
 * Mud Snails
 * Plankton

__**Tundra**__
Tundra is the coldest of all the biomes. It is noted for its frost-molded landscapes, extremely low temperatures, little precipitation, poor nutrients, and short growing seasons. Dead organic material functions as a nutrient pool. The two major nutrients are nitrogen and phosphorus.

Characteristics of tundra include:
 * Extremely cold climate
 * Low biotic diversity
 * Simple vegetation structure
 * Limitation of drainage
 * Short season of growth and reproduction
 * Energy and nutrients in the form of dead organic material
 * Large population oscillation

Tundra is separated into two types:
 * Arctic
 * Alpine

**__Arctic Tundra__**[[image:arctic.png align="right"]]
Arctic tundra is located in the northern hemisphere. The arctic is known for its cold, desert-like conditions. The growing season ranges from 50 to 60 days. The average winter temperature is -34° C (-30° F), but the average summer temperature is 3-12° C (37-54° F) which enables this biome to sustain life. Rainfall may vary in different regions of the arctic. Soil is formed slowly. A layer of permanently frozen subsoil called //permafrost// exists, consisting mostly of gravel and finer material. When water saturates the upper surface, bogs and ponds may form, providing moisture for plants. There are no deep root systems in the vegetation of the arctic tundra, however, there are still a wide variety of plants that are able to resist the cold climate. There are about 1,700 kinds of plants in the arctic and subarctic, and these include:
 * low shrubs, sedges, reindeer mosses, liverworts, and grasses
 * 400 varieties of flowers
 * crustose and foliose lichen

All of the plants are adapted to sweeping winds and disturbances of the soil. Plants are short and group together to resist the cold temperatures and are protected by the snow during the winter. They can carry out photosynthesis at low temperatures and low light intensities. The growing seasons are short and most plants reproduce by budding and division rather than sexually by flowering. The fauna in the arctic is also diverse:
 * Herbivorous mammals: lemmings, voles, caribou, arctic hares and squirrels
 * Carnivorous mammals: arctic foxes, wolves, and polar bears
 * Migratory birds: ravens, snow buntings, falcons, loons, sandpipers, terns, snow birds, and various species of gulls
 * Insects: mosquitoes, flies, moths, grasshoppers, blackflies and arctic bumble bees
 * Fish: cod, flatfish, salmon, and trout

Animals are adapted to handle long, cold winters and to breed and raise young quickly in the summer. Animals such as mammals and birds also have additional insulation from fat. Many animals hibernate during the winter because food is not abundant. Another alternative is to migrate south in the winter, like birds do. Reptiles and amphibians are few or absent because of the extremely cold temperatures. Because of constant immigration and emigration, the population continually oscillates.

__**Alpine Tundra**__
Alpine tundra is located on mountains throughout the world at high altitude where trees cannot grow. The growing season is approximately 180 days. The nighttime temperature is usually below freezing. Unlike the arctic tundra, the soil in the alpine is well drained. The plants are very similar to those of the arctic ones and include: Animals living in the alpine tundra are also well adapted:
 * tussock grasses
 * dwarf trees
 * small-leafed shrubs
 * heaths
 * Mammals: pikas, marmots, mountain goats, sheep, elk
 * Birds: grouselike birds
 * Insects: springtails, beetles, grasshoppers, butterflies

=__ **Grasslands** __=

Grasslands are characterized as lands dominated by grasses rather than large shrubs or trees

There are two types of grassland biomes:
 * Savannahs
 * Temperate Grasslands

__**Savannahs**__
Savanna is grassland with scattered individual trees. Climate is the most important factor in creating a savanna. Savannas are always found in warm or hot climates where the annual rainfall is from about 20-50 inches per year. It is crucial that the rainfall is concentrated in six or eight months of the year, followed by a long period of drought when fires can occur. If the rain were well distributed throughout the year, many such areas would become tropical forest. Savannas which result from climatic conditions are called climatic savannas. Savannas that are caused by soil conditions and that are not entirely maintained by fire are called edaphic savannas. These can occur on hills or ridges where the soil is shallow, or in valleys where clay soils become waterlogged in wet weather. A third type of savanna, known as derived savanna, is the result of people clearing forest land for cultivation. Example- In Africa, a heavy concentration of elephants in protected parkland have created a savanna by eating leaves and twigs and breaking off the branches, smashing the trunks and stripping the bark of trees. Annual fires then maintain the area as a savanna.

Savanna has both a dry and a rainy season. Seasonal fires play a vital role in the savanna's biodiversity.In October, a series of violent thunderstorms, followed by a strong drying wind, signals the beginning of the dry season. Fire is prevalent around January, at the height of the dry season. Fires in savannas are often caused by poachers who want to clear away dead grass to make it easier to see their prey. The fires do not devastate the community.

Other animals (which do not all occur in the same savanna) include giraffes, zebras, buffaloes, kangaroos, mice, moles, gophers, ground squirrels, snakes, worms, termites, beetles, lions, leopards, hyenas, and elephants.

__**Temperate Grasslands**__
Temperate grasslands are characterized as having grasses as the dominant vegetation. Trees and large shrubs are absent. The amount of rainfall is less in temperate grasslands than in savannas. Temperate grasslands have hot summers and cold winters. The amount of annual rainfall influences the height of grassland vegetation, with taller grasses in wetter regions. As in the savanna, seasonal drought and occasional fires are very important to biodiversity. However, their effects aren't as dramatic in temperate grasslands as they are in savannas.

[[image:grassland_biome.jpg width="442" height="309" align="center"]]
Soil: The soil of the temperate grasslands is deep and dark, with fertile upper layers. It is nutrient-rich from the growth and decay of deep, many-branched grass roots. The rotted roots hold the soil together and provide a food source for living plants. Each different species of grass grows best in a particular grassland environment (determined by temperature, rainfall, and soil conditions). The seasonal drought, occasional fires, and grazing by large mammals all prevent woody shrubs and trees from invading and becoming established. The various species of grasses include purple needlegrass, blue grama, buffalo grass, and galleta. Flowers include asters, blazing stars, coneflowers, goldenrods, sunflowers, clovers, psoraleas, and wild indigos. Precipitation in the temperate grasslands usually occurs in the late spring and early summer. The annual average is about 20-35 inches. The temperature range is very large over the course of the year. Summer temperatures can be well over 38° C, while winter temperatures can be as low as -40° C. The animals living in temperate grasslands include gazelles, zebras, rhinoceroses, wild horses, lions, wolves, prairie dogs, jack rabbits, deer, mice, coyotes, foxes, skunks, badgers, blackbirds, grouses, meadowlarks, quails, sparrows, hawks, owls, snakes, grasshoppers, leafhoppers, and spiders. There are also environmental concerns regarding the temperate grasslands. Few natural prairie regions remain because most have been turned into farms or grazing land. This is because they are flat, treeless, covered with grass, and have rich soil.

=__**Deserts**__=

There are 2 kinds of desert biomes;
 * Hot and Dry deserts
 * Cold deserts.

**Hot And Dry Deserts** - don't have very many plants - only animals have the ability to burrow underground - near the Tropic of Cancer or the Tropic of Capricorn - temperature ranges from 20 to 25 degrees C. Extreme temperature ranges from 43.5 to 49 degrees C. - have very little rainfall and/or concentrated rainfall in short periods between long rainless periods. This averages out to under 15 cm a year. - warm throughout the fall and spring seasons and very hot during the summer. - winters usually have very little if any rainfall - vegetation is very rare - plants are almost all ground-hugging shrubs and short woody trees - all of the leaves are replete (packed with nutrients) - adapted to survive in the environment - ability to store water for long periods of time - ability to stand the hot weather - animals include nocturnal carnivores, insects, arachnids, reptiles and birds.

- has snow in the winter instead of just dropping a few degrees in temperature - never gets warm enough for plants to grow. Just maybe a few grasses and mosses - animals also have to burrow to keep warm -some animals might be the same with those that you could find in Hot and Dry Deserts - found near the Arctic part of the world - temperature ranges from -2 to 4 degrees C and in the summer 21 to 26 degrees C a year - has rain around spring. Averages out to 15 - 26 cm a year - have quite a bit of snow in the winter. The summer and the beginning of spring are barely warm enough for a few lichens, grass and mosses to grow - plants are scattered: Areas with little shade - 10% of ground is covered with plants - all plants are either deciduous and more or less contain spiny leaves -has animals like Antelope, Ground Squirrels, Jack Rabbits and Kangaroo Rats
 * Cold Deserts**

__**Issue About the Desert Biome**__
There is currently a problem in the Desert about the greediness of people. There are people who go out there and cut cacti, and then, they sell these to make profit. This is similar to illegal logging, except there is no actual law against cutting cacti. The cacti found in the desert is extremely important in the biome. The flesh of the cactus is what many animals found in the desert eat. This provides them with the energy gained from the cactus's photosynthesis and the animal will also get the water that cacti store inside their stems. If the greedy people continue to cut down cacti, the population of cacti will decrease. This, in turn, will make the supply of water in the desert lower and there will be less plants where herbivores and omnivores can get their energy from. If there are less prey to feed on, the predators will get hungrier and hungrier until they die. This will eventually lead to the lessening of animals in the entire biome. From the simple act of greedy people cutting down multiple cacti for their own pockets, many animals die and a whole ecosystem is affected. There have been petitions for a law against cactus cutting, but there are very few countries that actually have these laws.

__**Rainforest**__
There are three types of Rainforests:
 * Tropical Rainforests
 * Temperate Rainforests
 * Boreal Forests

Climate
 * Tropical Rainforest**
 * - a forest of tall trees in a region of year-round warmth
 * - belong to the tropical wet climate group
 * - temperature rarely gets higher than 34 degrees C or drops below 20 degrees C
 * - average humidity is between 77 to 88%
 * - rainfall is often more than 100 inches a year
 * - usually have a brief season of less rain
 * - almost all rainforests are found near the equator
 * - covers less than 6% of the Earth's surface
 * - scientists estimate than more than half of the world's plants and animal speceis are found in rainforests
 * - produces 40% of the Earth's oxygen
 * - more kinds of trees than any other area in the world
 * - 70% of the plants are trees
 * - 100 to 300 species of plants in one hectare are a in South America
 * - 1/4 of all the medicines we use come from rainforest plants
 * - all tropical rainforests resemble one another in some ways
 * - many of the trees have straight trunks that don't branch out for 100 feet or more
 * - majority of the trees have smooth thin bark because there is no need to protect them from water loss and freezing temperatures
 * -also makes it difficult for plant parasites to get a hold on the trunks
 * - many trees have similar barks that it is difficult to identify it by its bark; many trees can only be identified by their flowers
 * - each of the 3 largest rainforest, American, African, and Asian, has a different group of plant and animal species
 * - different areas of the same rainforest may have different species
 * Temperate Rainforest**
 * obvious element is precipitation
 * precipitation can fall in the form of either rain or snow, with s[[image:18423023_f489f601bf.jpg width="429" height="284" align="right"]]now more likely to fall in higher elevations
 * annual temperature is above 0 degrees C, largely influenced by the nearby ocean
 * warmest of the temperate rainforests may have an average annual temperatures around 20 degrees C

Plants
 * dominated by big coniferous trees including Douglas fir and Western red cedar, etc
 * there are a number of deciduous trees here especially in warmer spots
 * mosses, ferns and lichens are very common

Animals
 * mammals like deers, bears and coyotes
 * has a number of slug species like the Banana slug
 * some have birds like the Clark's Nutcracker and the Blue Grouse
 * Boreal Forest**

It is also known as Taiga

Climate World Distribution Plants
 * is cold with average annual temperatures from about 5 deg rees C to -5 degrees C
 * precipitation varies from about 20 cm per year to over 200 cm
 * much of the precipitation comes in the form of snow
 * winters are cold and long, while summers are relatively short and cool
 * there is little evaporation because of snowmelt and low temperatures, so the ground is usually very moist during the growing season
 * growing season is short; usually less than 3 months
 * extends in broad bands across North America and Eurasia
 * lies to the south of the tundra and north to the deciduous forests and grasslands

[[image:2790040450_7121ab50e4.jpg width="359" height="258" align="center"]]
Animals Carnivores
 * coniferous trees are dominant plant form - they shed snow easily and retain their needles in the winter - include firs, pines, spruces, hemlocks and larches
 * there may be mosses and lichens
 * there are a number of cats and dogs
 * The cats range in size from the Siberian Tiger through the lynx to the bobcat. There are others like the Siberian Tigers

Herbivores
 * - range in size from the deer such as the Elk, to insects
 * An Elk in Europe is a moose in North America, and a Red Deer in Europe is North America's Elk ***
 * - other mammalian herbivores include the arboreal (tree-living) Porcupine and the terrestrial Snowshoe Hare

Check Up Quiz

1.) What are the three layers of a lake? 2.) What are Estuaries? 3.) Which type of biome has the characteristics of extremely high temperatures? 4.) How will cutting cacti affect the whole desert ecosystem? 5.) What is a boreal forest and what are its significant differences from tropical and temperate rainforests? 6.) Which biome is most suited to plant on? 7.) Which biome has the most precipitation?