Chapter 4 Ecosystems and Communities

Chapter 4 Ecosystems and Communities

4-1 The Role of Climate In the atmosphere, temperature, precipitation, and other environmental factors combine to produce weather and climate. weather - day-to-day conditions in the area climate - average yearly conditions of temperature and precipitation in a region

Factors that contribute to Climate Trapping of heat by the atmosphere Transport of heat by wind and water currents Amount of precipitation Latitude

The Greenhouse Effect Gases in the atmosphere (H 2 O, CO 2, and methane) trap heat in and warm the earth

THE EFFECT OF LATITUDE ON CLIMATE Earth is a sphere tilted on its axis and receives sunlight at different angles throughout the year Different latitudes = different angles of heating by the sun

Creates 3 climate zones Polar- cold and dry; sun s rays hit at low angles Temperate- between polar and tropical; most changes in light; temperature varies from hot to cold Tropical- near equator; direct or nearly direct light year around; hot and wet

Heat Transfer in the Biosphere Heat is moved by wind and air currents Warm air/water rises and cool air/water moves in. This creates currents.

Section 4-2 What Shapes an Ecosystem? Ecosystems are influenced by a biological and physical factors. Biotic factors = living (biological) influences on an organism Abiotic factors = nonliving (physical) influences on an organism Habitat = The biotic and abiotic factors where and organism lives This is an an organism s address

Niche Niche = all physical and biological conditions in which an organism lives and the way in which the organism uses those conditions. This is an organisms job

Niche includes Place in the food web (what organisms eats and what eats it) Tolerance levels Physical requirements Reproductive cycles

Community interactions Competition -Organisms attempting to use a resource at the same place and time - Competitive Exclusion Principal- no 2 species can occupy the same niche at the same time struggle for resources: water, nutrients, light, food, space

Predation - One organism captures and feeds on another - Predator- kills/eats - Prey- gets killed/eaten

symbiosis 2 species living closely together Mutualism = both species benefit from the relationship; flowers and insects; ants and aphids

commensalism = one species benefit and the other is neither helped nor harmed; barnacles and whales; orchids and tree

parasitism = one species lives on/in another and causes harm to the host; tapeworms and mammals; fleas, ticks and mites and mammals;

Ecological Succession Ecological succession series of predictable changes that occur in a community over time Caused by Slow environmental changes Sudden natural disturbances Primary succession On surfaces where no soil exists Volcano's, glacial melts, etc Pioneer Species- first species to populate after primary succession

Secondary succession occurs after natural events like fires Occurs when community is disturbed without loss of soil Marine succession Often occurs when large whales die and sink to the barren ocean floor 1. whale dies scavengers 2. nutrients decompose and support marine worms 3. oil in bones eaten by bacteria

Succession

Section 3: Major Land Biomes

Biome- complex of terrestrial communities that cover a large area; characterized by soil, climate, plants, and animals Plants and animals vary by tolerance to temperature and precipitation Microclimate- climate in a small area that differs form the surrounding climate 10 Major Biomes

Tropical Rain Forest Hot and wet Most species of plants & animals (species diversity) Soil lacks nutrients Close to the equator Orchids Black Jaguar Toucan Sloth Boa constrictor Jaguar Tapir

Tropical Dry Forest Seasonal rainfall; warm most of the year Deciduous trees & drought tolerant plants Rich soil Toucan Elephants Spot billed pelican Monitor lizard Bromeliads Tiger

Tropical Savanna Seasonal rainfall (more than desert, less than tropical forest) Warm Frequent Fires Grasses, short trees, shrubs, drought/fire resistant plants Giraffe Storks Aardvark Hyena Lion

Desert Dry, less than 25 cm of rain a year Extreme changes in temperature throughout the day Plants with short growth cycles Animals with high tolerance to temperature changes Kangaroo rat Roadrunner Mountain lion Mule deer Desert big horned sheep Golden eagle Creosote bush

Pronghorn antelope Temperate Grassland fertile soil Moderate precipitation Hot summers & Cold winters Rich grasses and shrubs Periodic fires; drought/ fire resistant plants Bison Polecat sunflowers Coyotes Black-tailed prairie dog Blazing stars Badgers

Temperate Woodland Squirrel and Shrubland Also called the chaparral Hot, dry summer with cool, moist winter Periodic fires Woody, evergreen shrubs with only leaves California quail Black-tailed deer Warbler Fox

Raccoon Temperate Forest Warm summer with cold, moderate winters Year around rain Deciduous and coniferous trees, mosses, and ferns Skunk Bobcat Turkey Black bear

Northwestern Coniferous Douglas Fir Forest Only on Pacific Coast from US up to Alaska Lush, mostly conifers (redwoods, etc) Bears and other large herbivores Elk beaver Barred owl Redwoods

Spruce Boreal Forest also known as taiga Snowshoe hare Northern hemisphere Long, cold winter, short summers, moderate precipitation Many coniferous trees Timber wolves Moose Lynx

Snowy owl Tundra Northern hemisphere Characterized by permafrost Small plants with short roots because of permafrost Cold & windy; little precipitation Migratory animals or animals with high tolerances for harsh conditions Bearberry Caribou Polar bear Artic willow Artic fox

Mountain Ranges Conditions vary with elevation Higher elevation = cooler and wetter Widespread distribution of plants and animals Polar Ice Caps Cold or frozen Mosses and lichens are predominant plants North = polar bears, seals, insects, mites South = penguins and marine mammals

Section 4: Aquatic Ecosystems (p 106-112) Aquatic ecosystems are characterized by: Depth Flow Water temperature Chemistry of water

Freshwater Ecosystems 1. Flowing Water Ecosystems Rivers, brooks, streams, creeks Animals adapt to rate of flow More plants and animals in slower sections of water 2. Standing Water Ecosystems Primarily lakes and ponds Water circulates

Cont 3. Freshwater Wetlands Wetland water covers soil or is present at or near the surface for at least part of the year Water is flowing, standing, fresh, salty, or brackish Bogs, marshes, or swamps Characterized by soil, plant life, and animals

Estuaries where rivers meet the sea à usually a wetland shallow, lots of light, influenced by tide Salt marsh à lots of salt tolerant grasses and temperate waters Mangrove Swamp à tropical, salt tolerant trees

Marine Ecosystems photic zone well lit, upper layer where ALL photosynthetic organisms live aphotic zone permanently dark; chemosynthetic autotrophs only

Ocean Zones Intertidal Zones Extreme changes Sometimes covered in water, sometimes dry Zonation horizontal banding of organisms in a habitat Coastal Zone Low tide line to the continental shelf Mostly in the photic zone

Cont Coral Reef Named for coral (calcium carbonate skeletons of animals that form the reef) Need warm water and light Open Ocean Extends from edge of continental shelf High pressure, no light, cold temperatures

Cont Benthic Zone Benthos à organisms that live attached to or near the ocean floor Zone where benthos live Most feed on detritus Chemosynthetic bacteria near ocean vents