Biology - Deforestation, Greenhouse effect and Greenhouse gases.
What are greenhouse gases?
These are the various gases, present in the atmosphere which absorb and emit heat radiation towards the Earth's surface in order to keep the earth warm enough to sustain life.
What is global warming?
This is the steady increase of temperatures on the Earth's surface.
How does deforestation affect biodiversity?
Loss of habitats - some species reside in the canopy of the forests and on the forest floors and when deforestation takes place, this results in loss of habitats, which eventually leads to some species becoming extinct.
What are 4 fruits/vegetables which originated in tropical forests?
Potatoes, maize, rice and coffee.
How is man affected by deforestation and loss of biodiversity?
When species go extinct, it causes the disruption of food webs within ecosystems causing other organisms to be affected and additionally, loss of biodiversity reduces mans reserve of genetic diversity.
How does deforestation affect climate change?
When trees carry out photosynthesis, CO2 from the atmosphere is converted into carbon in food and is stored in the woody parts of the trees. Logging releases carbon and removes the vegetation from the felled trees that would normally absorb CO2 from the air during photosynthesis. As a result, the built up carbon in the air contributes to climate change.
What are the uses of wood and agricultural land after Deforestation?
Wood is used for fuel, building material and pulp for paper while the cleared land is used to plant crops and or rear livestock.
Deforestation
The removal of tress from forests to provide wood and for agricultural land.
What are some human impacts on the greenhouse effect?
1. Although natural processes such as respiration and photosynthesis naturally maintain carbon levels in the atmosphere, human activities such as the burning of trees, fossil fuels and deforestation of tropical rainforests have resulted in increased carbon emission into the atmosphere. 2. The use of CFCs, that is, refrigeration coolants, aerosol propellants and Styrofoam, are 12,000x more effective than CO2 in trapping heat. 3. When cleared land is used for the rearing of livestock such as cows and sheep, when they past waste, the digested food contains large amounts of methane which is released into the atmosphere.
What are two other impacts of deforestation?
1. Disruption of water cycles - forests contribute significantly to the water cycle when trees release water vapor from their leaves during transpiration. Deforestation reduces transportation and can result in widespread droughts. 2. Soil erosion - soil that is exposed after deforestation can heat up and dry out. Without the protective cover of the forest canopy and the stabilizing effect of tree roots, torrential rainfall will result in soil being washed away and can eventually lead to flooding, once in rivers and streams.
What are 3 possible effects of global warming?
1. Droughts - warmer weather has led to water shortages and droughts in some parts of the world. 2. Forest fires - drier vegetation and low rainfall 3. Disruption of weather patterns - more powerful hurricanes,
What are 2 ways in which the greenhouse effect can be reduced?
1. Engage in different forms of travel - most of the popular modes of transportation require the use of fossil fuels, for example gasoline and jet fuel. By using public transport, carpooling, walking and biking lowers the amount of vehicles on the roads as well as, the amount of greenhouse gases being emitted. 2. Reduce the amount of carbon in the air - by planting trees, bamboo and other plants, in amount of carbon dioxide in the atmosphere decreases. The conservation of forests, wetlands, grasslands also assist in lesser carbon emission.
What are 3 causes of deforestation?
1. For agriculture - growing of crops and rearing of livestock. 2. Industrial uses - building of factories, housing developments and residential areas. 3. Mining - for the discovery of valuable minerals such as bauxite, gold, etc.
What are 3 ways in which the effects of deforestation can be arrested?
1. Reduce meat consumption - as the global demand for meat continues to increase, farmers are then forced to cut down trees for the purpose of rearing livestock. If the amount of meat consumption is reduced, the global demand for meat will also reduce and will eventually prevent further destruction of trees and and forests. 2. Use recycled products - by using recycled products, for example, paper, lowers the overall demand for timber, therefore decreasing the need to cut down more trees. 3. Raise awareness - by educating individuals on how their actions affect/contribute to deforestation, such as increased meat and palm oil consumption, the amount of deforestation can be reduced
Explain the human enhanced greenhouse effect.
1. The sun emits incoming short wave radiation (visible light) which passes uninterrupted through the atmosphere to reach Earth. 2. The heat energy emitted by the sun is absorbed by lands and oceans, heating up the Earth's surface. surface. 4. Heat then radiates from the Earth, in the form of Infrared Radiation towards space. 3. Some of the heat escapes to space while some is trapped and absorbed by the greenhouses gases in the atmosphere and is then reradiated in all directions. 4. Human activities such as the burning of fossil fuels, deforestation and the use of CFCs, increase the overall amount of GHGs in the atmosphere. 5. These human-inflicted activities cause extra heat to be trapped and re-radiated back to earth, causing an increase in the Earth's temperature.
What are the MAIN greenhouse gases?
Carbon dioxide, water vapor, methane, ozone and chlorofluorocarbons (CFCs)
What would take place if there wasn't a greenhouse effect?
The Earth's surface would experience a reduction in temperature of 30 degrees Celsius and it would not be able to sustain life as we know it.
Greenhouse Effect
The natural phenomenon that is responsible for keeping the earth warm enough to sustain life.
Biodiversity
The number of different species that can be found in an area.
