Human Impacts on the Environment Bio 2.2 2.2.1 2.2.2
Part One: Human Activities and the Environmental Impact • Population Growth • With more people on the planet there is less available area for wildlife, and a much higher risk of encounters with wildlife • Population growth creates more waste (pollution) • Population growth causes animals to look to humans for food • Bears eating trash • Deer eating peoples gardens
Pollution • There are several types of pollution • Water: Water pollution can cause fish to die in mass amounts, high levels of toxins in fish, which humans may eat, contaminating our bodies • Air: gases given off by cars, factories, machinery, even farm animals, causes the air to be less clean, raising the risk of respiratory problems • Ground: Chemicals / Oil leaking into the ground can cause plants to die, the toxins could make it into the water table, polluting the ground water • Neighborhoods built on old factory land where chemicals were dumped have been known to have a much higher incidence of cancer and diseases
Global Warming • Alters ecosystems due to climatic changes • Less rain in some areas, more rain in others • Colder weather in some areas, warmer weather in others • Caused by greenhouse gases being emitted from industrialization It is theorized that the massive amountsof air pollution from Asia is having a global impact on temperature. The picture shows smog, not fog
Burning of Fossil Fuels • Burning fossil fuels (Coal and Oil) not only contributes to greenhouse gases, but also endangers the areas and people who need to retrieve these from the Earth • Mining for coal is expensive and dangerous • Oil rigs in the oceans can be catastrophic if they leak or break, as seen in the Gulf of Mexico
Habitat Destruction • As more people populate the planet, more and more habitats are being destroyed for crop land, neighborhoods, etc. • Clear cutting destroys entire ecosystems, and potentially causes the loss of plants and animals that hold the key to producing life saving treatments
Nonnative Species • Nonnative species (also known as invasive species) have the potential to take over an area, killing off all native species • Nonnative species rarely have natural predators so nothing keeps their population numbers in check • The ball python is a native of Asia, and commonly kept as a pet, but when released they are detrimental to the native populations • Florida know has a hunting season for these invasive predators because they are greatly reducing the number of native species in the Everglades and altering the ecosystems
Florida Ball Python Disaster- all of these pictures are from the last few years in the Florida everglades
Part Two: North Carolina Ecosystems • North Carolina has a wide variety of ecosystems and challenges that face the health of them, all of which are man made.
Mountains • Acid rain effects can be seen in the mountains • Acid rain is caused by chemicals in the air produced by factories • Acid rain lowers the pH of soil so much that plants cannot live • Easy to recognize on Mount Mitchell
Beach Erosion • Beach development (houses, roads, bridges, hotels) all contribute to beach erosion • Dunes are necessary for wildlife, but if they are destroyed the sand and habitat will be lost
Piedmont Urban Development and Water runoff cause natural areas to be degraded and water ways to be polluted, reducing the health of the natural ecosystem and negatively impacting the plants and animals in this region
Hog Farm dangers- mainly near rivers • Waste lagoons on hog farms have the potential to massively pollute waterways if they leak, or spill over during large rainstorms. Pollution into waterways can create unsafe drinking water, mass fish kills, and ground pollution
Invasive plants- all over the state • Kudzu is a great example, it is not a native plant, imported from Asia to help with soil erosion, but it did its job too well • Kudzu can quickly cover entire trees, cars, etc. • When the kudzu covers native plants, they die off, and the only plant left that is thriving is the kudzu. Both native plants and animals suffer and their populations decline.
Part Three: Impact of humans on Natural Resources • Resource Depletion • As we deplete resources, such as oil and coal, we must dig/drill deeper to access the fuel, causing damage to the ground water and surrounding areas, as well as putting more people at risk • As people need more lumber, etc. rainforests are being destroyed for harvest • Once a rainforest is destroyed it takes hundreds of years for it to even begin to be a healthy ecosystem again
Deforestation • Reduces habitat for countless animals • Creates mudslides and runoff from storms, without trees and underbrush to absorb the rain water, it runs into storm drains, carrying mud with it, or devastating mudslides are possible
Pesticide Use • Pesticide use pollutes ground water • Pesticide use has been linked to ground contamination • Some old apple orchards that have been converted to neighborhood land have ground level contaminant levels that are deemed unsafe • In these cases, all the topsoil must be stripped and disposed of in hazardous material landfills and new topsoil brought in • Pesticide use has caused some pests to become resistant, creating a need for even stronger chemicals to be used • Pesticides kill indiscriminately • Helpful natural predators are also killed (such as ladybugs and praying mantis)
Bioaccumulation “Bioaccumulation is defined as the accumulation of chemicals in the tissue of organisms through any route, including respiration, ingestion, or direct contact with contaminated water, sediment, and pore water in the sediment.” – U.S. Environmental Protection Agency, 2000 • Basically- bioaccumulation is when organisms are exposed to contaminants and it accumulates in their tissues • Fish, such as Tuna, have very high levels of mercury and are not safe for pregnant women to eat
Part Four: Conservation and Stewardship- All Hope is not lost! • US Endangered Species Act (1973) • Made it illegal to harm any species on the Endangered Species or Threatened Species list • Habitat Protection • State Parks and Conservation areas (including greenways- there is one in Patton Park) are federally protected habitat • Habitat Corridors • Bridges and Tunnels are being built to allow animals (such as the panther in Florida) to safely cross above or below busy roadways to avoid being hit by cars
People are beginning to use sustainable materials (such as bamboo that grows very quickly) in building to help stop habitat loss from logging demands • Animals are being successfully reintroduced to areas through captive breeding programs • Exotic plants are being removed from areas and people are working to restore natural habitats • Factories are working to reduce pollution through cleaner processes and filter systems
Summary- Key Points • Deforestation has the potential to cause an increase in carbon dioxide levels (CO2) because the removal of millions of trees also removes their ability to photosynthesize and remove CO2 from our air • A rise in CO2 levels has been directly linked to global warming • Global warming does not mean it is always going to be hot- it means that as the Earth warms up, we will see big swings in hot and cold, dry and wet, etc. Places that have never seen snow will, and places that use to be very wet will begin to dry out
Key Points Cont’d 4. Acid rain not only harms trees and plants on mountain tops, but also has the potential to cause a decrease in plant and animal life in waterways 5. As more chemicals and toxins are released into the atmosphere, the ozone layer is negatively affected. -With less protection from the UV rays, the planet will begin to warm (Global warming) because more UV rays will be striking the planet
That is the end of the notes…now: • Answer the questions on the next sheet. Turn in (with your filled in notes) to Mrs. Paige. Make sure your name is on the first page of the notes. • When you have turned in your work, You will be given a review packet. Work on it for the remainder of class. You can work on any section you choose. DO NOT LOSE IT and bring it to class on Monday. If you want to, you can write your name on it and give it to Mrs. Paige so you won’t lose it. We will be working on it throughout the rest of the semester.