Transcript Biomes
Biomes The biosphere is divided into region called biomes. A Biomes is a group of ecosystems that exhibit common environmental characteristics . Earth’s Biomes 1. 2. 3. 4. 5. 6. 7. 8. 9. Tropical Rain Forest Desert Temperate Grasslands Savannas Temperate Deciduous Forest Conifer Forest-Taiga Tundra Marine Freshwater Earth’s Biomes Tropical Rain Forest • High temp • Heavy rainfall • Tall trees that branch at their tops forming canopies • Very little light reaches the floor • Epiphytes and vines • Equatorial – 4% of Earth’s land surface – Account for 20% of Earth’s net carbon fixation • Most diversity of species of any biome • Animals: – Birds, reptiles, mammals, amphibians Desert • • • • Hot & dry Less than 10” of rainfall per year Extreme temperature fluctuations Plants: – Cactus, sagebrush – CAM plants • Modification for water storage • Animals: – Rodents, kangaroo rat, snakes, lizards, arachnids, insects, and few birds Temperate Grasslands • Low annual rainfall • Grazing mammals (bison, antelope), burrowing mammals (prairie dogs & other rodents) Temperate Grasslands • Warm to hot summers, cold winters, moderate, seasonal prec, fertile soils, fires • Dominant plants: lush, perennial grasses and herbs, resistant to drought, fire and • Dominant wildlife: predators (coyotes, badgers, wolves, grizzly bear); herbivores (deer, antelope, rabbits, prairie dogs, bison); birds (hawks, owls, bobwhite), insects (ants and grasshoppers) • Geographic distribution: central Asia, N.A., Australia, central Europe, upland plateaus of S.A. Savannas • Grasslands with scattered trees • Warm temps, seasonal rainfall, compact soil, frequent fires due to lightning • Tropical, less rainfall than rain forest Savannas • Dominant plants: tall, perennial grasses, droughtand fire-resistant shrubs and trees • Dominant wildlife: predators (lions, leopards, cheetahs, hyenas, jackals), herbivores (elephants, giraffes, antelopes, zebras), birds (eagles, ostriches, weaver birds, storks), insects (termites) • Geographic distribution: large parts of eastern Africa, southern Brazil, northern Australia Temperate Deciduous Forest • Cold to moderate winters, warm summers, yearround precip, fertile soil – 70-150 cm annual precip • Dominant plants: broadleaf deciduous trees, some conifers, flowering shrubs, herbs, mosses and ferns – Broad-leaved hardwood trees that shed their leaves each year – Soil has top layer that is rich in humus, deeper layer of clay. If minerals are not taken up by plants roots, the minerals get into clay and are trapped Temperate Deciduous Forest • Dominant wildlife: deer, black bears, bobcats, nut and acorn feeders, omnivores (raccoons and skunks), songbirds, turkeys • Geographic distribution: eastern U.S., southeastern Canada, most of Europe, parts of Japan, China, and Australia Conifer Forest-Taiga • Long, cold winters; short, mild summers; moderate precip; high humidity; acidic, nutrient-poor soil – A little warmer and wetter than tundra, but long, severe winters and short,mild summers – NO PERMAFROST layer, but decay of evergreen needles makes soil acidic and mineral-poor • Dominant Plants: needleleaf coniferous trees, broadleaf deciduous trees; small, berry-bearing shrubs Conifer Forest-Taiga • Dominant Wildlife: predators like lynx and timberwolves; weasel family; herbivorous mammals (large and small); beavers; migratory songbirds • Geographic distribution: N.A., Asia, Northern Europe Tundra • Strong winds;low precip;short and soggy summers; long, cold, dark winters; poorly developed soils – Permafrost present – permanently frozen ground under the topsoil • Dominant Plants: mosses, lichens, sedges, short grasses (ground-hugging) Tundra • Dominant wildlife: birds and mammals that can withstand harshness; migratory waterfowl, shore birds, musk ox, Arctic fox, caribou; small rodents • Geographic distribution: northern N.A., Asia and Europe – Closest to poles Aquatic Biomes ~Marine~ • Oceans contain the largest amount of living material (biomass) of all of the biomes – but most of them are microscopic orgs!!! • Since oceans are huge, studied based on light penetration: – --photic zone (shallow, lots of light available) – --aphotic zone (deep, never receive sunlight) Estuaries and Tidal effects • Estuary – found on coast, partially surrounded by water; here, salt water and fresh water mix. • *see variations in SALINITY – salt concentration, so what grows/lives here varies enormously. Intertidal Zone • Tides – gravitational pull of sun and moon causes the rise and fall of ocean. • INTERTIDAL ZONE – portion of shoreline between high and low tide zones • *high levels of sunlight, nutrients, and oxygen, but low PRODUCTIVITY due to waves and movement Aquatic Biomes ~Fresh water~ EX. Lakes, ponds, rivers, streams • Light penetration still affects productivity – photic zone has high productivity, – aphotic zone has low productivity • But, bottoms of lakes and ponds have decay taking place (dead orgs drift to bottom, bacteria break them down and form detritus), so importance in CYCLES is enormous… Earth’s Biomes