Transcript Ecosystem
Chapter 19 Ecosystems Ecosystem All the living and nonliving elements in a given place. Ex: Marsh, coral reef, rain forest, and a city. Ecosystem They are not all the same size. –Ex. Can be as big as the Earth, or as small as the tip of your finger. Living things are adapted to their ecosystems. Not Adapted Community All the animals and plants living in one area within an ecosystem. Several communities can be in one ecosystem. Members of an ecosystem can belong to multiple communities. Ecological Pyramid Ecosystem (biggest) Community Population (one species) Organism (smallest) Balanced Ecosystems Balance ecosystems remain stable. Predator and prey populations will always be in balance Interrelatedness –A change or removal of one feature in an ecosystem may affect the entire system. Interrelatedness Predator vs Prey Ecosystem Recovery Succession -The gradual repopulating of a community by different species over a period of time. Succession of a Forest Ecosystem Changes 1.Short-Term (few months) – Quick succession – Ex. Change in seasons 2. Long-Term (many years) – Ex. Slow succession – volcanic eruptions/natural forest fires – global climate changes – Human activities – Introduction of nonnative species Short-Term Season Change Long-term Climate Change Long-term Climate Change Long-term Climate Change The Jurassic Era’s Al Gore Long-term Human Activities Human caused forest fires Pollution entering ecosystems Over development (building roads, logging, over irrigating) Over hunting (bringing species near extinction) Long-term Over Development Long-term Pollution Long-term Over Hunting Long-term Over Hunting Long-term Introduction of Nonnative Species They may have no natural predators to keep population in check. Brings in unnatural food and habitat competition They may become an unnatural predator, and wipe out another species. Long-term Introduction of a Nonnative Species Energy and Resources 19.2 Need for Energy The Earth at Night Sources of Energy 1. 2. 3. 4. 5. 6. Fossil fuels (most common) Sun Wind Alternative Sources Water Geothermal Nuclear How We Use Our Sources 1. Fossil Fuels Any carbon based fuel formed from the remains of plant and animal life. Coal, oil, and natural gas Nonrenewable Resources -any resource that is used faster than it can be replaced. We are running out of them Inefficient, dirty energy source 2. Solar Power The sun produces enough energy a day, to power the USA for one year. Solar power is renewable –Any resource that can be continually replaced. Harnesses the energy by using solar cells The problem is storing the energy. Solar Cells 3. Wind Power Oldest source of alternative energy Collected by windmills. Very low cost. Problem is that wind can be unpredictable. Wind Farms 4. Water Power Dams are built on fast moving rivers to create large holding places for water. Running water spins the turbines to generate clean efficient hydroelectric power. The building of dams can be very destructive to the near by ecosystems. Water’s other Source? Is Water a Renewable Resource? Thirst for WATER.PPS 5. Geothermal Energy The energy from heated steam/water within Earth’s crust near beds of molten magma. Hot steam and water are used to turn turbines to generate power. Problem is only a few areas of the world have access to this form of energy. Geothermal Power Plant 6. Nuclear Power Use nuclear fission. Reaction produces tremendous energy to heat water to turn a turbine. Very efficient energy little fuel is needed compared to coal. No air pollution Nuclear Power BAD NEWS -radioactive waste which can’t be disposed -power plants only last 30 years, then need to be completely shutdown -fear of meltdown Efficiency of Energy Energy is lost each time it is converted to another form. Fossil fuel burning plants only 30-40% efficient. How Can We Be More Efficient? Use alternative energy Use and Make vehicles that are more fuel efficient. Make Mass Transit more available Use energy efficient appliances. Be aware about how you are using your electricity at home. Energy Efficient Home Pollution and Recycling 19.3 What is Pollution? Contamination of the air, water, or soil from: –Litter –Smog and smoke –Dust and gases –Chemicals poured out Litter Litter Litter Smog and Gases Smog and Gases Chemicals in the water Pollution Two Types: –natural Volcanic eruptions and natural fires –Manmade More common Natural Pollution Manmade Air Pollution 1. Particulates (PM) -dust, smoke, asbestos 2. 3. 4. CO and CO2 gases -products of any combustible fossil fuel NO2 and SO2 –formed from burning fossil fuels which lead to acid rain. VOCs and ozone –volatile compounds that can cause breathing and health problems -increase in smog Particulates CO2 is on the rise. The affects of acid rain VOCs Manmade Water Pollution Water is our most vulnerable resource that is polluted by: –Industrial Waste –Pesticides (DDT) –Fertilizers (causes Eutrophication) –Boat oil/gasoline spills –Pouring chemicals down a drain. –Flushing the toilet Industrial Waste DDT Eutrophication Eutrophication Oil Spills Manmade Land Pollution Litter Contaminants in the soil (Hg and Pb) Running out of room for our garbage. Litter ex. cigarettes Garbage The average person throws away a half a ton a garbage a year. Towns tax residents based on how much garbage they produce. Where do we put our garbage? Reducing Pollution Using non-fossil fuel burning efficient energy. Reducing Use – save electricity, carpool, buy less Reusable Products Recycling – Town make money from people recycling more, reducing taxes. – Buy materials made from recycled materials Recycling Batteries Paper Glass and cans Most plastics (check for the triangle) What else can we do? Reuse!!!! Compost Use less plastic (green bags instead) Think how “Stuff Happens” after we do things. Remember in the words of Bill Nye, – WE CAN CHANGE THE WORLD