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Ecosystems. Key terms. Autotrophs/Producers Heterotrophs/Consumers Decomposers Ecological Community Community-level interactions Keystone species Trophic level Limiting Factors Know the difference and be able to compare: Biotic factors vs. Abiotic factors Food chains vs. Food webs
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Key terms • Autotrophs/Producers • Heterotrophs/Consumers • Decomposers • Ecological Community • Community-level interactions • Keystone species • Trophiclevel • Limiting Factors • Know the difference and be able to compare: • Biotic factors vs. Abiotic factors • Food chains vs. Food webs • Niche vs. habitat
Structure Daily Goal/Unit Questions: What defines an ecosystem? How to classify and explain the interactions w/in an ecosystem.
Unit Questions for Understanding • What is ecology? • What basic processes keep us and other organisms alive? • What are the major components of an ecosystem? • What happens to energy in an ecosystem? • What are soils and how are they formed? • What happens to matter in an ecosystem? • How do scientists study ecosystems?
Unit Questions for Understanding • What factors the earth’s climate? • How does climate determine where the earth’s major biome’s are found? • What are the major types of desert biomes? • What are the major types of grassland biomes? • What are the major types of forest and mountain biomes? • How have human activities affected the world’s desert, grassland, forest, and mountain biomes?
Structure • Levels of Ecological Organization: • Atom • Molecule • Cell • Organism • Population • Community • Ecosystem • Biosphere
Levels of Ecological Organization Individual: One organism within a species. =1
Levels of Ecological Organization Population: One group of species that live together and interact in one area.
Levels of Organization Community: All Biotic populations within one area that interact together.
Levels of Ecological Organization Ecosystem: A set of communities within one area that interact.
Life on Earth • Life on earth depends on 3 interconnecting factors: • The one-way flow of energy (high-quality) • Sun to earth and living things • Photosynthesis (low – energy) • Can not be recycled • Cycling of matter or nutrients (round – trip) • Only certain amount of matter and nutrients on earth. Required for life sustainability • Depending on the cycle, takes seconds to centuries. • Gravity • Allows us to hold onto the atmosphere surround the earth, which allows life to be sustained.
Abiotic Factors Non-living components: • Water, air, nutrients • Rocks • heat, solar energy • Salinity • Temperature • pH • Wind TOK: • How can we measure abiotic factors? • What are some methods we can use?
Biotic Factors All components that consists of living and once lived. • Plants • Animals • Microbes • Dead organisms and parts of organisms • Waste products from organisms TOK: • What are ways we can measure Biotic Factors? • What are some methods we can use? • Are these methods as precise as measuring Abiotic? Why or why not?
Ecology Ecology – study of relationships in the natural world. Ecologist – the person or scientist that study these interactions Applied ecology – Uses information from ecologists to better understand issues like developing effective vaccination strategies, managing fisheries or large ranches without over harvesting, depleting genetic diversity, designing land/marine conservation reserves for threatened and endangered species (spp) and modeling how ecosystems may respond to global climate change, natural and human disasters.
The Gaia Hypothesis: Is the Earth Alive? • Some have proposed that the earth’s various forms of life control or at least influence its chemical cycles and other earth-sustaining processes. • The strong Gaia hypothesis: life controls the earth’s life-sustaining processes. • The weak Gaia hypothesis: life influences the earth’s life-sustaining processes.
Biomes • A collection of ecosystems that share similar climatic conditions, vegetation and animals. In relation to ecosystems • Most changes in ecosystems are caused by climate change, species movement in and out of the ecosystem and ecological succession. • Species basic physical conditions for survival also play a role in an ecosystem. • Geography has an important impact on ecosystem changes because of climate circulation patterns (atmospheric and oceanic) and climate zones. • Factors include: • Temperature ranges, moisture availability, light and nutrient availability, and altitude (height above or below sea level).
Climate • Weather is a local area’s short-term physical conditions such as temperature and precipitation. • Climate is a region’s average weather conditions over a long time. • Latitude and elevation help determine climate.
Biomes Climate Zones: • Divided into 4 distinct areas - • Tropics – warmest, wettest regions • Equator - where the sun’s heat and energy are the strongest. • Subtropics – high-pressure creates dry zones @ 30° latitude North and South. • Poles – Driest and coldest zones @ 60° latitude. • Reason for climate zones – • The angle of impact of the sun’s rays on the earth • Equator = 90° Angle • Latitude and altitude change the ambient heat energy the further you move away from the equator or away from the surface. • The Earth is tilted at a 23.5° angle creating seasons as it orbits around the sun.
Biomes broad geographical areas that stretch the globe which contain many ecosystems with a wide range of diverse groups of organisms that are adapted for those specific temperatures and precipitations. • Division of biomes (with subdivisions) • Aquatic • Freshwater – swamp forests, lakes, ponds, streams, rivers and bogs • Marine – rocky shore, mud flats, coral reefs, mangrove swamps, continental shelf, deep ocean • Terrestrial • Deserts – hot and cold • Forests – Tropical, temperate, and boreal(taiga) • Grasslands – Tropical or savanna and temperate • Tundra – arctic and alpine
Biomes Aquatic Biomes (Freshwater and Marine) Covers ¾ of the earth’s surface. Include – open ocean, coral reefs, estuaries, lakes, rivers Large bodies (oceans & lakes) are layered Surface – warmest with most amount of light filtration. Depends on the movement and mixture from deep to surface for nutrients.
Biomes - Aquatic Wetlands – Freshwater and saltwater swamps, marshes, bogs • All have standing water, water table is at the surface, ground is saturated • Little oxygen creates special soils and decay takes place slowly. • Creates the coal we use today over a geological time period. • Bogs – no surface water but have a layer of vegetation that lays on top of the water. • Bacteria found here carry out chemical processes that produce methane and hydrogen sulfide.
Biome - Aquatic Freshwater – lakes, rivers, ponds, streams, groundwater. • Very small portion of the Earth’s water supply. • Used to supply water to homes, industry, recreation, and agriculture. • Rivers and streams are used to transport materials from land to ocean. • Abundant in biotic factors. • Estuaries – mouths of rivers where ocean water and freshwater mix. – rich in nutrients, impt. in breeding sites for fish (salmon).
Biome - Aquatic Intertidal zones: • Areas exposed to the alternation of air during low tide and ocean waters during high tide. • Constant movement of water transports nutrients in and out of the zone. • Major economic resources found here, i.e. seafood • Susceptible to pollution from land and freshwater sources. • Extreme variations in environmental conditions occur here.
Biome - Aquatic Open Ocean: • Called pelagic region • Tend to be low in nitrogen and phosphorus • Benthos – bottom portion • Primary food source is dead organic material that falls from above. • Upwellings – Deep ocean waters • Cold and dark, life is scarce • Rich in nutrients – dead organic material (organisms) fall from surface • Upward flows of waters brings those nutrients to the surface allowing abundant growth of algae and animals at the surface. • Commercial fishing occurs in these areas because of the abundant and diverse fertile organisms found here. • Hydrothermal vents – occur in deep ocean where plate tectonic processes create vents of hot water with a high concentration of sulfur compounds. • Chemosynthetic organisms live here • Water pressure is high, and temps range from boiling to frigid.
Biomes - Terrestrial Tundra – treeless plains that occur in the harsh climates of low rainfall and low average temps. • Covers 10% of earth’s land. • Dominant vegetation – grasses, mosses, lichens, flowering dwarf shrubs • Two types • Arctic – High latitudes, Antarctica and N. Canada/Greenland • Alpine – High elevation, Himalayas, Rocky Mountain Ranges, Swiss Alps • They differ by the types of animals found and latitude/altitude. • Permafrost – permanently frozen ground, extremely fragile
Biomes - Terrestrial Boreal (Taiga) Forests: • Forests of cold climates • High latitude and High altitude. • Dominated by conifers (trees), form dense small trees. • Spruce, firs, pines, aspens and birch to name a few. • Biological diversity is low • Commercially valuable resources • Include large mammals, small rodents, many insects, birds, raptors • Contain some of the Earth’s largest remaining wilderness • Conservation is important (Yellowstone)
Biomes - Terrestrial Temperate Deciduous Forests: • Climates are somewhat warmer than Boreal. • N. America, Eurasia, Japan • Dominant vegetation • Maples, beech, oaks, hickory, chestnuts • Taller trees than Boreal • Dominant animals • Smaller mammals that tend to live in trees (squirrels), birds, rodents, insects • Larger mammals tend to live in the younger forests where tree population is smaller • Long dominated by humans • Important nature preserves (Yellowstone, Yosemite) • Very few remaining uncut, old growth forests left • Fire is natural and recurring, but not as dominant as in Boreal
Biome - Terrestrial Temperate Rain Forests: • Temps are moderate and precipitation exceeds 250cm/year • Rare but spectacular • Dominant vegetation – • Coniferous and evergreen trees • Redwood, Sequoia, Douglas Fir, Western Cedars • Northern Hemisphere – • California, Oregon (Redwood, Sequoia) • Canada • Southern Hemisphere – • New Zealand • Major source of Timber crops, esp. in N. America • Low diversity of plant and animal species because of the low sunlight available on the forest floor.
Biome - Terrestrial Temperate Woodlands: • Temp patterns are like deciduous forests, but climate is slightly drier. • N. Hemisphere – • New England, Georgia, Caribbean islands. • Dominant veg – • Small trees – pinion pine, evergreen oaks, ponderosa pine • Stands are open and wide allowing plenty of sunlight to reach forest floors • Fast growing and used for timber crops • Animal species – • Deer, small/med mammals, birds, rodents
Biome - Terrestrial Temperate Shrublands: • Mediterranean climates, low rain fall and cool seasons, Drier climates called Chaparral • Coastal California (mid to lower), Chile, S. Africa, Med region of Europe (Ancient Greece and Rome). • Miniature woodlands with dominant shrubs • Highly modified by humans because of the climate and is conducive for ranching and farming. • Young tree/shrub lands – conducive to fires • Used to decorate many streets and gardens
Biome - Terrestrial Temperate Grasslands: • Too dry for forests, too moist for deserts. • Dominant plants – • Grasses and flowers • Soils have a deep organic layer, perfect for farming • i.e. – Midwest, Kansas, Wyoming • Covers areas from Canada down to Northern Oklahoma. • Abundant animal species • Large mammals – horses, American Bison, Kangaroos (Australia), antelope and other large herbivores (Africa) • Small mammals – rodents (prairie dogs), foxes
Biome - Terrestrial Tropical Rain Forests: • Avg temp is high and relatively constant the whole year, rainfall avg is high and frequent. • Northern South America, Central America, Western Africa, N. Australia, Indonesia, Philippines, Borneo, Hawaii and parts of Malaysia. • Diverse plant and animal species – • Approx 2/3 of all flowering plants live here. • Mammals tend to live in trees – Monkeys, sloths, etc. • High diversity of bird species and insect species