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Topic 7
Human Impact on Ecosystems
Name of Human Activity | Description of human activity | The effects on the ecosystem | What can we do to help? |
---|---|---|---|
DIRECT HARVESTING | species are removed from their habitats and sold as pets, ornaments, or house or garden plants. | Many animals die. Over-harvesting can lead to endangerment or sometimes even extinction. | Laws can help protect species but the laws create a bigger demand for these products. |
DEFORESTATION | Destruction of forests for space, resources, | habitats destroyed,endangered species,loss of biodiversity,ecosystem instability, reduced cycling and absorption of minerals | Preserve areas, Restrict cutting of trees, Decrease demand for tree products. |
Loss of Biodiversity | Species are lost, It can be caused by many human activities, such as habitat destruction, It can also be caused by plowing an area to plant a single crop, such as corn or wheat. | Species are lost. Loss of genetic diversity that could be used for genetic engineering, medicines, treatments, and creating more productive and pest-resistant crops. Negative effect on the proportion of gases in the atmosphere.Negative effect on food web. | Limit habitat destruction and protect with laws and restrictions.Farmers should try and limit pesticides and chemicals. |
Imported species | Humans import or release a species from one environment (usually the native environment) to another foreign environment. | The new species become pests.No natural enemies so they rapidly overpopulate.Destroy the environment and may compete more successfully and eliminate native species. | Introduce a natural predator but can cause more problems. Pesticides but may harm us or other species. Disease organism that only affects imported species.Quarantine. Chemical scent treatments, radiation to sterilize. |
INDUSTRIALIZATION | Development of an economy in which machines produce many of the products people use.Adds to quality of life.Higher demands for energy, products, etc. | Adds to quality of life but adds pollution to the environment.Increases the demand for energy water, and fuels.Power Plants add pollutants to air and water.Nuclear Fuel makes thermal pollution and radioactive waste and withdraw a lot of water from enviro | 3R's , Decrease demand for products made in industries. |
NITRATE WATER POLLUTION | Fertilizers and animal wastes are nitrogen- based compounds that act as fertilizers, increasing the growth or plants, algae, and some aquatic bacteria. | Reduction of oxygen due to overgrowth of algae and plants (plants and animals consume oxygen 24 hours a day for respiration). Suffocation of organisms in water. | 3 R's, organic fertlizers, reduce fertilizer use |
TOXIC WASTE | Wastes dumped are into waterways from cities, farms, or industries.Chemical fertilizers and pesticides washed into water. | Chemicals are toxic to organisms in the water.Chemicals collect in cells of algae,plants, producers and the concentration increases as it moves through the food chain. Ex: DDT and Bald Eagle | 3 R's, laws/fines that prohibit dumping, alternative pesticides and fertilizers, water treatments |
THERMAL POLLUTION | Power plants and industries use water to cool the machines or materials and the hot water is released back into rivers and streams. | Warm water cannot hold as much oxygen as cold water. Organisms suffocate, or need to find a new home. | Reduce the need for power.New methods that will reduce damage. |
ACID RAIN | Sulfur and Nitrogen are produced by burning fossil fuels. When released into the air, they combine with moisture in the atmosphere and wind up in the water cycle. | Acid rain (low pH rain (pH 2-5)) damages plants makes them more susceptible to disease algae dies. | 3 R’s, Alternative energy sources with less pollution. |
SMOG | Caused by automobile exhaust and industries when burning fuel. | Toxic to inhale, weather can trap in pollution. People with respiratory diseases may be in danger. | 3 R’s, Cleaner emissions |
GLOBAL WARMING | CO2 released by burning fossil fuels (cars, industries) traps more heat therefore more warming. Deforestation increases the amount of C02 in the atmosphere. | Increase in global temp.over a long period of time...Possible melting of ice caps.Possible flooding in coastal regions and destruction of some coastal ecosystems. | Find and use energy sources that do not add C02.Preserve and grow trees. |
OZONE DEPLETION | CFC’s in the atmosphere caused by(coolants in refrigerators, air conditioners, aerosol cans, manufacturing plastic foam)Ozone is good. Ozone protects us from the damaging UV rays of the sun and reduces our risk of skin cancer due to mutation. | Ozone shield from UV light is being destroyed. Too much UV Radiation causes mutations, kills cells, causes skin cancer, and kills plants which would disrupt food chains. | safe alternatives, international laws to reduce use of CFC's in products. |