Communities & Biomes

Communities&Biomes

Communities • Have you ever wondered why we don’t have polar bears in Mississippi? • Why we don’t have grizzly in Mississippi? • Abiotic and biotic factors interact and result in conditions that are suitable for life for some organisms and unsuitable for other organisms.

Abiotic and biotic factors Polar bears live near the north pole. Their white fur makes them hard to distinguish from the surrounding ice and snow, enabling them to stalk the seals and walruses that serve as their primary food.

Limiting factors Environmental factors that affect an organism’s ability to survive in its environment, such as food availability, predators, and temperature, are limiting factors.

Ranges of tolerances Some species can tolerate conditions that another species cannot, for example, catfish can live in warm water with low amounts of dissolved oxygen, which other fish species such as bass or trout, could not tolerate. All species have a certain range of tolerances that they can withstand.

Succession If grass were no cut on a lawn, what would it look like in one year, five years, and twenty years? Ecologists refers to the orderly, natural change and species replacements that takes place in the communities of an ecosystem as succession.

Primary Succession Lava flowing from the mouth of a volcano is so hot it destroys everything in its path, but when it cools it forms new land. This new land is un-colonized by any life until a pioneer species begins to settle it. The colonization of new species is called primary succession.

Pioneer Species • Lichen- is an example of a pioneer species it is a combination of alga and fungus.

Climax Community After the primary succession and species have changed many times a relatively stable community appears this community is known as a climax community. A climax community is characterized by complex food webs, many different species of organisms, and little or no succession.

Secondary Secession Secondary Secession refers to the sequence of community changes that takes place after a community is disrupted by natural disasters or human actions.

Biomes A biome is a large group of ecosystems that shares the same type of climax community.

The Biosphere is divided into regions called Biomes. Each Biome is occupied by characteristic communities or ecosystems of plants and animals that share adaptations which promote survival within the biome.

Aquatic Biomes The portion of the marine biome that is shallow enough for sunlight to penetrate is called the photic zone. Deeper water that never receives sunlight is called the aphotic zone.

Marine Biomes = Saltwater Ocean Zones • Photic Zone = sunlight area • Aphotic Zone = cold, dark area • Intertidal Zone = area between high & low tides (area in & out of water twice a day) • Neritic Zone =shallow, sunlight area of ocean • Oceanic Zone = the rest of the open ocean

Marine Biomeinclude Estuaries (where oceans meet rivers)bays, mud flats, and salt marshes

Estuary • lots of light • lots of nutrients • large variation in temperature and salinity • some areas exposed to air during low tide • plants include trees, grasses, and seaweed • animals include birds, fish, clams, crabs, and shrimp

Aquatic Biomes • An estuary is a coastal body of water, partially surrounded by land, in which freshwater and saltwater mix.

Aquatic Biomes The portion of shore line that lies between the high and low tide lines is called the intertidal zone.

Intertidal Zones(where oceans meet land) • area exposed to air twice a day during low tide • organisms must protect themselves from dehydration and crashing waves • plants include Fucus, Laminaria, kelp, • animals include crabs, mussels, sea stars, sea anemones, chitons, and snails

Marine BiomeContinental Shelf(the shallow oceans that border continents) Alaska Bering Sea Shelf

Plankton are small organisms, that live in the waters of the photic zone.

Neritic Zones(area over the continental shelf) • area where photosynthesis takes place • most productive area of the ocean • plants include plankton, and seaweeds like Sargassum • animals include coral, mollusks, crustaceans, sea turtles, and fishes

Marine BiomeCoral Reef (masses of corals that reach the ocean surface)

Marine BiomePelagic Ocean • low nutrient levels • low productivity • part light, part dark • wide range of pressure and temperature • contains fewer species • producers include photosynthetic protists and bacteria at surface, and chemosynthetic bacteria at volcanic vents • consumers include fish, whales, dolphins, clams, crabs, and worms

Aphotic zone • In the aphotic zone where the lack of light is darker than any night, and the pressure is hundred of pounds per square cm. there are still organisms that survive. 90% of the ocean is more than a km. deep. Organism that live at these depth still depend on sunlight, even if it is indirectly, for energy. What adaptations might help these organisms survive in this environment?

Marine BiomePelagic Ocean (the deep ocean)

Freshwater Biomesinclude ponds, lakes, • have low salt concentration (most freshwater biomes have less than 1% salt) • plants include lilies, algae, rushes, cattails • animals include birds, fish, otter, beaver • two types: • Eutrophic = rich organic matter and nutrients, and murky • Oligotrophic = very little organic matter

Freshwater BiomesStreams and Rivers • have low salt concentration • water flows down a slope • the greater the slope, the faster the current and the lower the nutrients • higher concentrations of O2 • plants include algae, cattails, shrubs, • animals include fish, birds, snails, flatworms, insect larvae….

Terrestrial Biomes • characterized and named according to the climax vegetation • climax vegetation determines which animals will live there • eight types- • Tropical Forest • Savannah/Grasslands • Desert • Temperate Deciduous Forest • Northern Coniferous Forest • Taiga • Tundra • Polar Region

TUNDRA • Terrestrial = land • Tundra- a treeless land with long summer days and short periods of winter sunlight • Permafrost- frozen layer of soil that lies only a few inches from the surface. (Permanently frozen)

Tundra • is extremely cold and dry • short growing season and permafrost (permanently frozen soil) • during the summer, the thawing topsoil supports a grassland type community with grasses, sedges, mosses and other vegetation tolerant of soggy soils • Animals include caribou, musk oxen, owls, foxes, hares, and wolves

Taiga • winters are cold, and precipitation is in the form of snow. • Soil is low in nutrients and highly acidic • are characterized by coniferous forests (pines, firs, and other trees with needles). • Taiga- a and of larch, fir, hemlock, and spruce trees, also called the northern coniferous forest.

Temperate Deciduous Forest • Temperate forest- Broad-leaved hardwood trees lose their foliage annually (70 to 150 cm) • This area is dominated by deer, rabbits, squirrels and black bear.

Temperate Deciduous Forests- • have warm summers and cold winters (red), moderate precipitation (green), and rich soil with decaying organic matter and worms and fungi. • contain deciduous trees that shed their leaves during the winter (beech, birch, maple, oaks, and willows), an adaptation to poor growing conditions (short days and cold temperatures). • animals include deer, fox, woodchucks, and squirrels

Grasslands • Grasslands- Large communities covered with grasses and similar small plants. • Grasslands contain fewer tan ten to fifteen trees per hectare, though larger numbers of trees are founds near streams and other water sources.

Temperate Grasslands • receive less water and are subject to lower temperatures than are savannas. • the North American prairie is an example.

Savannas- • subject to high temperatures (red), and low rainfall (green). • are tropical-subtropical grasslands with scattered bushes and trees. • animals include long-legged, hoofed herbivores (like bison, antelopes, cattle, and zebras).

Desert • Desert- an arid region with sparse to almost nonexistent plant life. • Deserts usually get less than 25 cm of precipitation annually. • Desert plants sometimes have spines, thorns, or poisons that act to discourage herbivores. • Desert animals are usually small nocturnal creatures. (Kangaroo rat)

Deserts- • are hot and dry. • soil is sandy and nutrient poor • growth of annual plants is limited to short periods following rains. • other plants have adapted to the hostile conditions with leathery leaves, deciduous leaves, or leaves reduced to spines (cacti). • many animals have thick skins, conserve water by producing no urine or very concentrated urine, and restrict their activity to nights.

Tropical Rain Forest • Tropical Rain Forest- have warm temperatures, wet weather, and lush plant growth. (200-600 cm) • The tropical rain forest is home to a diverse range of species. (more species per square acre than any other place)

Tropical Rain Forests • are characterized by high temperature (red) and heavy rainfall (green). • vegetation consists mostly of tall trees that branch only at their tops, forming a spreading canopy that allows little light to reach the forest floor. • epiphytes (plants that live on other plants) and vines commonly grow on the trees, but due to lack of light, little grows on the forest floor. • typical animals include monkeys, lizards, snakes, and birds.

Question 1 • The removal of which of the following organisms would have the biggest impact on a marine ecosystem? • A. Fishes • B. Whales • C. Shrimp • D. Plankton

Question 2 • An undersea volcano erupts creating a new island off the coast of South Carolina. Life slowly starts appearing on the island. What would probably be the first species to grown and survive? • A. Maple trees B. Finches • C. Linchens D. Grasses

Question 3 • The changes in communities that take place on a new island would best be described as _________. • A. Primary succession • B. Secondary succession • C. Tertiary succession • D. None of the above

Question 4 • Which of the following is true? • A. Temperature forests have more rainfall than tropical rain forests. • B. Tropical rain forests have more species of trees than temperate forests. • C. Temperate forests are closer to the equator than tropical rain forests. • D. Tropical rain forests are younger than temperate forests.

Question 5 • The annual rainfall is 300 cm and the average temperature is 15°C. What type of forest is being described? • A. Tropical rain forest • B. Coniferous Forest • C. Temperate Rain Forest • D. Temperate Forest

Question 6 • A lack of food prevents further growth in a deer population. This is an example of a __________. • A. Range of tolerance • B. Limiting factor • C. Photic zone • D. Biome

Question 7 • A deep sea fisherman catches an ocean fish. This fish, like others of the same species, has no developed eyes. Its habitat is most likely the ___________. • A. Intertidal zone • B. Aphotic zone • C. Photic zone • D. Zone of intolerance

Question 8 • Locations of biomes are usually determined by ______________. • A. Temperatures and altitude • B. Temperatures and precipitation • C. Altitude and precipitation • D. Soil type and temperature

Question 9 • The kangaroo rat conserves its water and obtains all its from the food it eats. In what ecosystem is the kangaroo rat more likely to live? • A. Tropical rain forest • B. Taiga • C. Desert • D. Savanna

Communities & Biomes