Ecology

Ecological Levels of Organization

The Earths Climate influences the structure and distribution of terrestrial biomes. Seasons Bodies of water mountains

Annual mean temperature (C) Figure 40.8 Desert Temperate grassland Tropical forest 30 Temperate broadleaf forest 15 Annual mean temperature (C) Northern coniferous forest Figure 40.8 A climograph for some major types of biomes in North America Arctic and alpine tundra 15 100 200 300 400 Annual mean precipitation (cm) 4

Terrestrial Ecosystems Tundra Taiga Temperate Deciduous forest Grasslands Tropical rain forests Deserts

Tundra 20% of Earth’s surface Long cold winter, short summer (6-8 weeks) 20 cm rainfall per year Permafrost – frozen layer beneath topmost layer Nutrient poor soil No trees, short grasses, lichens and moss Lemming, grouse, musk ox, snowy owls, lynx, snowshoe hares, polar bears, wolves, caribou

Tundra

Coniferous forests Taiga Temperate Rain Forest 11% of Earth’s surface Cone-bearing trees (spruce, fir, pine) Bears, moose, beaver and muskrat, wolves, In mountains = wolverines and mountain lions Temperate Rain Forest East coast of Canada and United States Large coniferous trees, rich soil, rainfall Squirrels, lynx, amphibians, reptiles, birds

Taiga and Temperate rainforest

Temperate deciduous forests Below Taiga, US!! Eastern United States, Europe and Eastern Asia Moderate climate, good rainfall, Seasons! Deciduous trees (lose leaves yearly), form canopies with varied growth. Variety of flora and fauna due to rich soil, climate, rainfall and protection.

Temperate Deciduous forest

Tropical Rain Forest South America, Africa and Indo-Malayan region Warm climate, plentiful rainfall, min. 190 cm Most diversity in flora and fauna and numbers Canopy, understory, forest floor Number of species not identified yet, most live in trees Poor soil

Shrublands Shrubs – shorter than trees South Africa, Western North America, shores of Australia California has Chaparral- type of shrubland without dense undergrowth and flammable. Mule, deer, rodents, lizards and scrub jays

Shrublands

Grasslands Annual rainfall greater than 25 cm but can not support trees. Include Russian steppes, South American pampas, North American prairies Bison, squirrels, mice, prairie dogs, rabbits, hawks, snakes, coyotes and foxes. Fertile soil, heavy farming

Grasslands

Savannas Cool, dry season followed by hot rainy season Central and Southern Africa, Australia, southeast Asia and South America Grasses with few trees with deep roots (Acacia) Large herbivores, elephants, giraffes, zebra, antelopes, wildebeest, carnivores: lions, hyenas, cheetahs, leopards

Savannas

Deserts Northern and Southern Hemispheres near equator 30% Earth’s surface, rainfall below 25cm Little or no vegetation, hot days, cool nights Desert plans have waxy cuticles to store water, ex. Cactus, sagebrush Reptiles (lizards and snakes), running birds, rodents, fox, hawks and insects

Deserts

Aquatic Ecosystems Freshwater and Marine Wetlands Lakes Coastal Ecosystems Oceans

Wetlands Classified by vegetation Marshes Swamps inundated by water, contain rushes, reeds and other grasses Contain waterfowl and small mammals Productive ecosystem Swamps Dominated by woody plants or shrubs (cypress, red maple and tupelo) American alligator

Wetlands

Wetlands Continued Bogs Characterized by acidic waters, peat deposits, and sphagnum moss. Most water comes from precipitation Nutrient poor Cranberries, orchids Moose

Bogs

Lakes Body of fresh water Classified by nutrient content Oligotrophic – nutrient poor Eutrophic – nutrient rich Seasonal temperatures in lake, relate to seasonal distribution of species in lake Plankton important to ecosystem Phytoplankton – photosynthetic algae Zooplankton – minute animals, eat phytoplankton

Lakes

Lakes continued Life zones Littoral zone – closest to shore, contain plants, habitat for fish, invertebrates, and reptiles Limnetic zone – sunlit body of lake, small fish Profundal zone – below level of light penetration, zooplankton, catfish Benthic zone – sediment at soil water interface, silt, sand detritus (dead organic material), worms, snails, clams

Lake Zones

Coastal Ecosystems Estuaries freshwater and seawater meet and mix. Include mangrove swamps and salt marshes Occur at mouth of river Abundance of nutrients Biologically diverse and productive “nursery of the sea”

Estuary

Coastal Ecosystem Seashores Littoral zone – between low and high water marks Barnacles, brown algae, oysters, mussels, sea dollars, sea birds

Seashore

Oceans Cover approx. ¾ of the Earth 2 divisions Pelagic division – open water Benthic division – ocean floor

Pelagic and Benthic divisions