Transcript ECOLOGY
ECOLOGY Honors: Ch 2 and 4 Magnet- Ch 46-49 Terms to know: • Ecology-study of interaction between organisms and their environment • Biosphere • Biotic vs. abiotic factors • Population • Community • Ecosystem (includes abiotic factors) • Biome Ch 36-Ecological levels of organization Section 3-1 Go to Section: Ecosystem Interactions • Habitat vs. Niche • What’s the difference? Community Interactions • Competition • Predation • Symbiotic relationships – Mutualism-ex-Lichens – Commensalism-ex-lichens and a tree – Parasitism-ex-mosquitos and us! Flow of energy in ecosystem • Words to know: autotrophs, heterotrophs, herbivore, carnivore, omnivore, detrivore • Energy flow: food chains, food webs • Ecological pyramids (Only 10 % of available energy moves up the pyramid). See p. 44 Section 3-2 Ecological Pyramids Energy Pyramid Shows the relative amount of energy available at each trophic level. Organisms use about 10 percent of this energy for life processes. The rest is lost as heat. Biomass Pyramid Represents the amount of living organic matter at each trophic level. Typically, the greatest biomass is at the base of the pyramid. Go to Section: Pyramid of Numbers Shows the relative number of individual organisms at each trophic level. Global cycles • Water -evaporation, transpiration, precipitation • Carbon -photosynthesis and respiration • Nitrogen -relies on bacteria • Phosphorus -weathering of rock The Water Cycle Section 3-3 Water cycle Condensation Precipitation Evaporation Transpiration Runoff Seepage Root Uptake Go to Section: Carbon Cycle • Depends on two main processesPhotosynthesis and Respiration • Remember the equations for both! Figure 3-13 The Carbon Cycle Section 3-3 Carbon Cycle CO2 in Atmosphere CO2 in Ocean Go to Section: Nitrogen cycle • Most nitrogen is in the atmosphere • Plants can only use nitrogen in the form of ammonium or nitrate • Bacteria convert atmospheric nitrogen to ammonium or nitrates, which is absorbed by plants • There are other bacteria that can convert these molecules back to atmospheric nitrogen Figure 3-14 The Nitrogen Cycle Section 3-3 Nitrogen Cycle N2 in Atmosphere NH3 Go to Section: NO3and NO2- Phosphorus Cycle • Depends heavily on the weathering of rock • Plants absorb dissolved phosphate ions from the soil • Also, decomposers can return phosphates back to soil • Because weathering is a slow process, phosphorus is often a limiting nutrient to plant growth Ch 3-Communities and Biomes • Community- group of interacting organisms that occupy the same area at the same time • Limiting factor- any abiotic or biotic factor that restricts the numbers, reproduction or distribution of organisms (ex-sunlight, water, temp, nutrients, space, etc). All organisms have a range of tolerance Two types of Succession 1. Primary Succession: a. Creates new colonies of organisms in new areas where no soil exists (EX: islands formed by volcanoes) b. takes a long time b/c soil(break down of rocks) c. Pioneer species – 1st organisms to move into an area d. Community continues to grow until limiting factors, environ. change , or natural disasters e. Climax community - stable, mature; not much change occurring 2. Secondary succession a. Changes that occur to a community after a natural disaster or environmental destruction b. "Old" species die and new species may move in c. This one doesn’t take as long as primary because the soil is already established. Biomes Each set of Biomes is defined by a unique set of abiotic factors-particularly climateand has a characteristic ecological community. Figure 4-17 The World’s Major Land Biomes Section 4-3 Go to Section: Biomes of the Earth Tropical rain forest Temperate grassland Temperate forest Tundra Tropical dry forest Desert Mountains and ice caps Tropical savanna Temperate woodland and shrubland Northwestern coniferous forest Boreal forest (Taiga) Ten Major Biomes Compare/Contrast Table Biome Precipitati Temper Soil Diversity Trees on4-3 ature Section Tropical high hot poor high dense Rain Forest Tropical Dry Forest Tropical Savanna Desert Temperate Grassland Shrubland (chaparral) Go to Section: Grasses variable mild rich Sparse ** tropical RF are the most diverse of all biomes moderate medium medium variable mild clay moderate sparse dense low variable poor moderate summer rich hot summer summer poor low, hot winter moderate moderate sparse moderate absent sparse dense low medium absent Temperate mode summer rich deciduous rate moderate, Forest winter cold **biome classificati ons usually don’t include icecaps dense sparse sparse high summer mild, winter cold rocky, acidic low dense low Summer mild, winter cold poor low absent Medium **know-permafrost Coniferous Forest (Boreal)inc ludes taiga Tundra high Figure 4-17 Zones of a Marine Ecosystem Section 4-4 Marine Ecosystems land Coastal ocean Open ocean 200m 1000m Photic zone 4000m Aphotic zone 6000m Ocean trench 10,000m Continental shelf Go to Section: Continental slope and continental rise Abyssal plain • Aquatic ecosystems: – Freshwater: a-flowing, b-standing c-wetlands -Estuaries- where fresh water merges with salt water. Very diverse -Marine: Intertidal; Pelagic (photic and aphotic); benthic (area along ocean floor) Page 80-81. The abyssal zone is the deepest region of the ocean (deepest point is over 7 miles deep). Why is the sea salty? Go to http://www.myuniversalfacts.com/2006/05/why-is-sea-salty.html Causes of Ecological Problems • Acid Precipitation – Results from the presence of sulfur oxides and nitrogen oxides in the air – Come from the burning of fossil fuels • Greenhouse Effect – Due to a rise in atmospheric carbon dioxide and methane – Carbon dioxide released from the combustion of fossil fuel More causes • Ozone depletion – Due to CFC’s used as refrigerants and propellants – CFC’s turn ozone into oxygen gas • Biological magnification – Because of pyramid of numbers, small concentrations of toxins in an environment become concentrated to dangerous levels in higher trophic organisms • Habitat destruction Population Dynamics • Population density: number of organisms per unit area • Dispersion- may be uniform, clumped or random. Depends on available resources. Section Outline Section 5-2 • Limits to Growth A. Population Limiting Factors 1. Density-Dependent Factors a. b. c. d. Competition Predation Parasitism and Disease Essentially anything “biotic” 2.Density-Independent Factors: a. abiotic- weather and climate, natural disasters (bottlenecks), human activities (CFC’s, Burning fossil fuels, etc). Go to Section: Concept Map Section 5-1 Population ecology Population Growth can be Logistic growth Exponential growth characterized by No limits on growth Unlimited resources represented by Constant growth rate J-shaped curve characterized by Limits on growth which cause a Falling growth rate Go to Section: represented by S-shaped curve Figure 5-4 Logistic Growth of Yeast Population Section 5-1 Carrying capacity Time (hours) Go to Section: Human Population Growth & historical events Industrial Revolution begins Agriculture begins Plowing and irrigation Bubonic plague Group discussion • What are some specific factors that have resulted in the growth of the human population? • What is biodiversity? • How have humans threatened biodiversity? Give some specific examples • **Make sure you know the difference in renewable vs nonreneweable resources