* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download ECOLOGY The study of our ecosystems
Survey
Document related concepts
Biodiversity wikipedia , lookup
Biogeography wikipedia , lookup
Restoration ecology wikipedia , lookup
Overexploitation wikipedia , lookup
Conservation agriculture wikipedia , lookup
Storage effect wikipedia , lookup
Biological Dynamics of Forest Fragments Project wikipedia , lookup
Human impact on the nitrogen cycle wikipedia , lookup
Reconciliation ecology wikipedia , lookup
Biodiversity action plan wikipedia , lookup
Habitat conservation wikipedia , lookup
Triclocarban wikipedia , lookup
Sustainable agriculture wikipedia , lookup
Theoretical ecology wikipedia , lookup
Transcript
ECOLOGY The Study of Our Ecosystems **Last Unit of Biology** ECOSYSTEMS Ecosystems are important units of the natural world. Humans are part of ecosystems and depend on them for food and many products. Without healthy ecosystems, humans would be in trouble! Important Terms to Know: • Ecology : the study of the interactions between organisms and their environment (biotic and abiotic). • Biotic: Living Biotic Factors: living, once living, and waste of an organism • Abiotic: Nonliving Abiotic Factors: oxygen, water, rocks, sand, sunlight, temperature, climate Important Terms to Know: • Habitat : a place where organisms live • Niche: the “role” of an organism in its environment, It includes the place where the organism lives as well as all the interactions it has with its biotic and abiotic environment. Seal Habitat Important Terms to Know: • Species: a group of similar organisms that can reproduce and give rise to fertile offspring. • Population : a group of organisms of the same species that live together in the same area. Since they are members of the same species, they interbreed • Community : a group of various species (populations) that live in the same area and interact with each other • Ecosystem : all organisms that live in a particular place together with the biotic and abiotic environment. (A community of organisms and their abiotic environment) Bee Population Community In this ecosystem, what are the abiotic factors and the biotic factors? Biotic •fish • turtle • bacteria • plants •dragonfly • waste material Abiotic •water • sunlight • rocks • soil •Oxygen •Carbon dioxide Ecosystem BIODIVERSITY: • Variety of organisms in a given area Physical factors affect biodiversity o Extreme temperatures decrease biodiversity o Limited water and food decrease biodiversity High biodiversity = more able to resist damage Low biodiversity = unhealthy ecosystem Stop and Jot! Draw a population of rabbits in their appropriate ecosystem. SUCCESSION: When we observe an ecosystem, it may look like an unchanging feature of the landscape, however all ecosystems change. As the ecosystem changes, the types of species it supports also change. The replacement of one kind of community by another at a single place over a period of time is called succession Forest Lake CHARACTERISTICS OF SUCCESSION: Stages of succession are described by a dominant plant and animal species Each stage of the succession Influences the environment which leads to the next “stage” Pioneer species -first species to colonize a new habitat Climax community -“final” stage of the succession Examples of Succession-Change in an Ecosystem: Volcanoes/Fires Volcanoes/fires devastate land – leave it changed New organisms appear First organisms to appear – pioneer species Small , fast growing plants Other plants replace pioneer species: grasses, shrubs, trees Eventually forest – Equilibrium after Succession Succession Examples of Succession: Bare Rock Lichens and mosses -break down the rock to begin to produce soil Pioneer grasses and ferns build up the soil Herbaceous plants Shrubs & bushes Trees Examples of Succession: Pond & Sand Dune Sand Dune Pond Examples of Succession: Abandoned Farm Abandoned Farm • First Year-annual weeds • Second year-ragweed/golden rod • Third year-grasses • Fourth year-pine trees • Fifth year-oak trees Examples of Succession: Pine Barrens Fire Fire (recall Pine Barrens Fire-1995) Area was restored by 2007 Stop and Jot! Draw succession in environment after a forest fire. Major Biological Communities As you drive along the United States, you will notice a change in the plants and animals based on climate • Climate – average weather condition in an area over a long period of time • Biome – large region characterized by a specific kind of climate and certain kinds of plant and animal communities •Biomes – determined by temperature and precipitation Organisms can only live within a certain temperature range Major Biological Communities Two types of biomes: terrestrial and aquatic Terrestrial Biomes Aquatic Biomes Terrestrial Biomes Grouped by latitude into tropical , temperate and high-altitude Tropical Biomes-warm temperatures Located near equator – low latitudes, warm, receive different amount of rain Tropical rain forests – large amounts of rain, warm all year, greatest biodiversity Savannas – tropical grasslands, long dry season, short wet season: zebras, giraffes, lions, elephants Tropical deserts – very little rain, less water, fewer plants, less animals Rain Forestabundant rain fall Savanna-short wet season Desert-little rain fall Temperate Biomes-moderate temperatures Mid-latitude between 30-60 degrees, wide range of temperature Temperate grasslands – moderate precipitation, cooler temperatures than savannas: bison Temperate forests – mild climate, plenty of rain, deciduous and evergreen trees: deer, bears, raccoons Temperate deserts – little precipitation, wide range of temperatures: coyote, armadillo Forest-plenty of rain Grasslands-moderate precipitation Desert-little precipitation High Latitude Biomes-cold temperatures Cold temperatures 60 degrees and higher in latitude Taiga – coniferous forests, cold, wet climate – winters long, most precipitation falls in summer: moose, wolves, bears Tundra – very little rain, short plants, water frozen most of year: foxes, lemmings, owls, caribous Taiga-wet climate Tundra-permafrost Aquatic BIOMES • Largest biome 70% of earth is covered by water. It is also the most stable biome because water temperature does not change easily Organized into freshwater ecosystems, wetlands estuaries and marine ecosystems , Aquatic Biomes- Freshwater, Wetlands Freshwater– lakes, ponds, rivers Freshwater Wetlands – provide a link between the land and fully aquatic habitats Wetland Aquatic Biomes- Estuary and Marine Estuary – freshwater from a river mixes with salt water from an ocean Example: Peconic Bay Estuary • Marine – salty waters of the oceans Marine Stop and Jot! 1. How do you figure out which biome you are in? 2. Choose 1 biome and draw it. ENEGY FLOW IN ECOSYSTEMS • Everything that organisms do requires energy . Every species must somehow get food for energy. When an organism dies, it is eaten by scavengers and decomposed by bacteria. At each step of this process, energy flows through the ecosystem. TROPHIC LEVELS Each step in energy transfer through an ecosystem – trophic level TROPHIC LEVELS Primary source of energy - sun Producers-(Plants) turn energy from the sun into energy they use Consumers - organisms eating other organisms o Herbivore -animals that feed on plants and plant materials o Carnivore -animals that feed on other animals Predators- kill and consume prey (tigers) Scavengers -feed on dead animals they find(buzzards) o Omnivore -animals that feed on both plants and animals (humans) Decomposers (saprophytes) - break down remains of organisms ( bacteria, fungus) TROPHIC LEVELS Fourth Trophic LevelTertiary consumer-carnivore Third Trophic LevelSecondary consumer-carnivore Second Trophic LevelPrimary Consumer (Herbivore) First Trophic Level-Producer Food Chains Energy flow from one trophic levelto the next First trophic level - producers Second trophic level - herbivores - eat producers Third trophic level - consumers - eat herbivores Carnivore - meat eating animal Omnivore - meat and vegetative eating animal Food Webs Energy never flows in a simple chain Most organisms eat more than one type of food. Complicated, interconnected group of food chains LOSS OF ENERGY • Energy stored in producers and consumers when eaten is lost as heat into the environment • Not recycled • The Ten Percent Rule – only about 10% of energy from producers are stored when eaten Energy Pyramid Shows the loss of energy at each trophic level Producers at the base of the pyramid – contains MOST energy Big predators at the top of the pyramid – contains LEAST energy Biomass Pyramid • Also considered BIOMASS PYRAMID Stop and Jot! Draw a food web. Draw the energy pyramid which goes along with your food web. CYCLING OF MATTER Water, carbon, oxygen, nitrogen, and phosphorus are five of the most important substances for life. An ecosystem must be able to cycle these kinds of matter in order to support life. Each cycle involves a reserve of the nutrient, a mechanisms for it to be obtained by plants and animals, and a way to return the nutrient to the reserve. Water Cycle Moves water between the atmosphere, land and oceans • Water vapor condenses , falls to earth's surface – precipitation Some water percolates into soil - ground water Runs across surface into rivers, lakes, oceans Heated by sun - evaporates into atmosphere Evaporation by plants - transpiration Carbon and Oxygen Cycle • Cycles tied closely together Carbon cycle - moves carbon from nonliving environment into living things and back Animals and plants cycle both carbon and oxygen throughout environment Plants use CO2 during photosynthesis - builds organic molecules Carbon and Oxygen Cycle-continued O2 is released from photosynthesis - animals use this to break down organic molecules ( respiration ) to release energy and CO2 used by plants Carbon released into atmosphere as CO by 2 combustion burning of substances ie: trees, fossil fuels (oil/coal) Nitrogen Cycle • Need nitrogen to make proteins Nitrogen circulates among air, soil, water and organisms 78% air is nitrogen - can not be used as a gas, must be changed to a different form Bacteria in soil and roots break down gaseous nitrogen into a usable form – Nitrogen Fixation Plants absorb fixed nitrogen Animals eat plants which contain nitrogen Phosphorus Cycle phosphate to make DNA • Movement of phosphorus in different chemical forms from surroundings to organisms and back to surroundings • Found in soil , rock dissolves in water to form phosphate • Roots of plants phosphate absorb • Organisms eat plants, reuse phosphate • When organisms die, phosphate returned to soil • Need POPULATIONS In the 1850’s about 2 dozen rabbits from Europe were introduced into Australia. The rabbits had plenty to eat, no competition and no predators. By 1950, there were 600 million rabbits! They ate so much vegetation that the numbers of native plants and animals declined and crops were damaged. What is a Population? Do you remember the definition? Write it down again A group of organisms of the same species that live together in one place at one time and interbreed • Populations may be small or large • As organisms are born, others die therefore the size may stay relatively constant • If a population grows too fast, environmental problems may occur Population Growth Scientists use population models to show growth in real populations Growth, shrinkage depends on births, deaths, immigration and emigration Immigration– movement of individuals into population Emigration – movement of individuals out of population A plot of population growth against time on a graph creates a population growth curve Growth curves can be Exponential growth or logistic growth Exponential Growth • More births than deaths • Numbers increase by a certain factor in each successive time period • J shaped curve • Small population size – slow growth • Large population size – very fast growth Logistic Growth Population growth limited by food, predators, disease Only a certain number of organisms can be supported by ecosystem Carrying capacity – largest population that environment can support at any given time (due to resources available) Carrying Capacity Logistic Growth-continued Logistic growth – population growth starts with a minimum number of organisms and reaches a maximum depending on carrying capacity of habitat S shaped curve Carrying Capacity FACTORS AFFECTING POPULATION SIZE • Abiotic– weather, climate, technology • Biotic – food, predators, humans Human Population World population > 7 billion Better sanitation, hygiene, disease control, agricultural and science technology Throughout history – population >10 million 2000 years ago – 300 million During industrial revolution – population began to grow exponentially Estimated 9 billion by 2050 INTERACTIONS IN COMMUNITIES Interactions in communities can take many forms. Predators and prey are locked in a struggle for survival. Competition for food, parasites and hosts try to get ahead of one another. Some organisms depend on one another for survival. Co-evolution -when two species are so closely dependent upon each other that they need to evolve together PREDATOR-PREY INTERACTIONS (+,-) Predation – one organism kills another for food Predator-prey relationships develop adaptations in response to one another (Co-evolution) Parasitism(+,-) Parasite – organism that feeds and lives on its Host Host almost always larger than parasite Parasite-host relationships develop adaptations in response to one another (Co-evolution) ie: tapeworms live in digestive system Herbivory(+,-) Animals eat plants Plants try to defend themselves by thorns, spines, chemicals/poisons Other Interactions Symbiosis – relationship which 2 species live in close association with each other Mutualism and commensalism Mutualism (+,+) Relationship where both species benefit The organisms develop adaptations in response to one another (Co-evolution) Ie: Shrimp and fish on coral reefs clean the bodies of large fish and turtles Commensalism (+,0) • Relationship where 1 species benefit , the other is neither harmed nor helped • Ie: Remora and shark Stop and Jot! Draw and describe an interaction between two organisms. SHAPING COMMUNITIES No organism can live everywhere. Each organism has its own set of conditions where it can live and where it does best. Some plants can survive in deserts and not in places with a lot of water. Other plants will out compete the desert plants and they will die. Carving a Niche • Recall the difference between a habitat and a niche: Habitat Place where an organisms lives Niche Role of an organism in its environment, where it lives, what it eats, how it influences its environment Niche Niche – unique position occupied by a species, both in terms of its physical use of its habitat and its function in an ecological community Includes the role an organism plays in the community Ie: beavers cutting down trees with their sharp teeth to build a dam Competition For Resources Species occupying the same niche will compete for food, shelter and resources One species will dominate over another species The species which loses either dies out, or migrates Some species -divide resources no competition ie: warbler birds feeding on the same insects in different portions of the same tree Different Warbler Birds occupying different parts of the same tree, therefore different niche! Competition For Resources continued Predation – reduces effects of competition More – biodiversitymore resiliency if catastrophe strikes All species of an ecosystem may depend on one species – keystone species Example: Sea Otter in North Pacific Number of sea otters decreased Sea otters feed on sea urchins As sea otter number ↓, sea urchin numbers ↑. Sea urchins feed on kelp. ↑ in sea urchins destroyed THE ENVIRONMENT We depend on the environment for food, water, air, shelter, fuel, and many other resources. Human actions can affect the quality and availability of these resources. The study of the impact of humans on the environment is called environmental science. HUMANS AND THE ENVIRONMENT • 7 billion people, population to exceed 10 billion before it stabilizes • Humans live in almost every kind of ecosystemon Earth • As population increases, impact on environment increases • As population increases, impact on environment increases AIR POLLUTION Caused by natural processes - volcanoes Caused by burning of fossil fuels release CO2, SO2 (sulfur dioxide) and NO2, NO3 (nitrogen oxides) into air Causes respiratory problems; results in; acid rain damages the ozone layer; affects temperature global Acid Rain Acid rain – precipitation has a high concentration of sulfuric or nitric acid (caused by pollution ); damages forests and lakes Ozone Layer Ozone (O3) layer – protects life from UV rays; damaged by chlorofluorocarbons (CFC’s) in spray cans and refrigerator coolant GLOBAL WARMING/CLIMATE CHANGE Greenhouse effect – warming of the surface and lower atmosphere of Earth when CO2 and water vapor absorb and reradiate heat Greenhouse effect – necessary to keep Earth’s temperatures stable Global temperatures rising steadily Cause believed to be increase in CO2 (air pollution) May have serious environmental problems – polar ice caps, melting loss of polar species habitat , rise in sea levels, destruction of coastal ecosystems and homes, more common hurricanes, typhoons, droughts Climate Change Video (7 min) WATER POLLUTION Due to fertilizers , pesticides , livestock farms, industrial waste, oil runoff, septic tanks, unlined landfills Polluted surface water percolates through soil to groundwater Pollutants run off land into rivers – both aquatic habitats and public water are contaminated ie: DDT (pesticide) harmed bald eagle, endangered Alga blooms because of fertilizer runoff – deplete dissolved O2 in water, organisms die SOIL DAMAGE Soil Erosion World needs fertile soil for food – agriculture • Soil erosion – materials of Earth’s surface are worn away and transported from one place to another by wind, gravity or water • Destroys fertile soil • Roots help hold soil together protecting from erosion • Removal of vegetation; soil erodes • Farming may lead to soil erosion – plowing Soil Conservation Sustainable agricultural practices help conserve fertile soil Terracing – change steep field into flat steps (stops gravity erosion) Cover crop – restores nutrients in soil Crop rotation – plant different crop every year, slows depletion of nutrients Contour plowing – rows plowed in curves along hills instead of straight lines – act as dams to prevent water erosion Terracing Cover Crop Contour Plowing ECOSYSTEM DISRUPTION Population size increasing – effecting every ecosystem, diversity of life suffering Results in loss of biodiversity , food supplies, potential cures for diseases, balance of ecosystems that supports all life on Earth Habitat Destruction Deforestation – over last 50 years, half of world’s tropical rain forests cut down or burned for timber, pastureland, farmland Rain forest disappears – loss of biodiversity, possible extinction Loss of Biodiversity • Disappearance of species food affects webs • Keystone species disappearance may cause other species to disappear • Biodiversity affects stability of organisms and sustainability of populations Invasive Species • Introducing nonnative species into an environment • Ie: Zebra mussel – introduced to Great Lakes – disrupted ecosystem (no native predators ), too many mussels now – native species suffering, also causing clogs in pipes of water treatment facilities Extinction • Death of every member of a species • Caused by disruption to ecosystems • Ie: red panda, 2 anticancer drugs developed from rosy periwinkle (flower in Madagscar) threatened by deforestation ENVIORONMENTAL SOLUTIONS Protecting the environment is critical to human well-being. With new technologies and the effort of individuals and governments, many environmental problems can be solved. CONSERVATION AND RESTORATION • Conservation – protects existing natural habitats • Restoration – clean up and restore damaged habitats • Prevents problems from happening! REDUCE RESOURCE USE • Reduce use of resources (water, fossil fuels) and wastes produced (use ceramic plates instead of paper plates) • Reuse goods ie: plastic bags and utensils • Recycle – process of reusing things instead of taking more resources from the environment ie: cans, paper, plastics TECHNOLOGY • Advances led to production of cars and industry – pollution • Advances can lead to due to solutions scientific research • Protect environment – cleaner energy sources ( renewable resources vs. non-renewable resources), waste management, clean pollution Non-renewable Resources Non-renewable resource : natural resource, cannot be re-made, re-grown or regenerated on a scale comparative to its consumption; exists in a fixed amount; being consumed faster than made by nature Oil Natural gas NON - Renewable Resources used for power Coal Renewable Resources • Renewable resource : replenished by natural processes at a rate comparable or faster than its rate of consumption by humans or other users Wind Solar Renewable Resources used for power Lumber Corn Water Technology Advances • Hybrid cars, hydrogen fuel cells, solar, wind, water power ENVIRONMENTAL AWARENESS • Addressing environmental issues – conservation groups, individuals and governments work together • Education – people aware of environmental issues and how to help address issues • Helping to solve the issues, support efforts to protect environment – advocacy PLANNING FOR THE FUTURE • In order for populations to thrive, sustain quality of life and keep resources – must plan for the future • Planning – avoid damaging the environment and solve issues at hand • Governments must help plan - enforce laws and limitations on developers and protect resources ( renewable and non-renewable ) Global Warming What causes the change? Implications of the change. What can we do about it? Ozone Depletion Acid Rain