4.4 climate change
Green House Gases: Carbon dioxide and water are the most significant greenhouse gases.
Carbon dioxide is released into the atmosphere by:
-Cell respiration in living organisms
-Combustion of biomass and fossil fuels
Carbon dioxide is then removed from the atmosphere by:
-Photosynthesis
-Dissolving in the oceans
Carbon dioxide is released into the atmosphere by:
-Cell respiration in living organisms
-Combustion of biomass and fossil fuels
Carbon dioxide is then removed from the atmosphere by:
-Photosynthesis
-Dissolving in the oceans
Threats to Coral Reefs from increasing concentration of dissolved carbon dioxide.
-Ocean acidification leads to death of coral polyps and algae (zooxanthella)
-CO2 reacts with water to form carbonic acid, this dissociates into hydrogen and hydrogen carbonate ions.
-Reef building corals need carbonate ions to build their skeletons.
-Ocean acidification leads to death of coral polyps and algae (zooxanthella)
-CO2 reacts with water to form carbonic acid, this dissociates into hydrogen and hydrogen carbonate ions.
-Reef building corals need carbonate ions to build their skeletons.
Temperature Rise and the Arctic:
-Melting of permafrost results as rise in sea levels
-Change in climatic patterns
-Expansion of temperate species, which equals to a reduction in range for arctic species (loss of ice habitat)
-Disturbance to food chains/webs/trophic levels
•Changes in distribution of prey species affecting higher trophic levels
•Increased detritus decomposition
-Melting of permafrost results as rise in sea levels
-Change in climatic patterns
-Expansion of temperate species, which equals to a reduction in range for arctic species (loss of ice habitat)
-Disturbance to food chains/webs/trophic levels
•Changes in distribution of prey species affecting higher trophic levels
•Increased detritus decomposition
Methane and nitrogen are other gases that have less impact as greenhouse gases.
-Methane is emitted from waterlogged habitats, and from sites where organic wastes have been dumped.
-Nitrous oxide: is released naturally by bacteria
-Methane is emitted from waterlogged habitats, and from sites where organic wastes have been dumped.
-Nitrous oxide: is released naturally by bacteria
The impact of greenhouse gases depends on its ability to absorb long-wave radiation as well as on its concentration on the atmosphere. Factors that determine warming impact of greenhouse gases:
-The amount of gas absorbs through long-wave radiation
-The concentration of the gas in the atmosphere (depends on the rate at which it is released into the atmosphere, and how long it stays there)
Methane causes much more warming per molecule than carbon dioxide, but it is at a much lower concentration in the atmosphere
-The amount of gas absorbs through long-wave radiation
-The concentration of the gas in the atmosphere (depends on the rate at which it is released into the atmosphere, and how long it stays there)
Methane causes much more warming per molecule than carbon dioxide, but it is at a much lower concentration in the atmosphere
The greenhouse effect is a natural phenomenon transmission of incoming shorter-wave radiation through atmospheric gasses:
-25% of short wavelength radiation that passes through the atmosphere is absorbed before it reaches the Earth’s surface
-75% of short wave radiation reaches the earth’s surface and converted to heat
-Re-radiation of longer-wave radiation is reflected back to Earth by greenhouse gases
-25% of short wavelength radiation that passes through the atmosphere is absorbed before it reaches the Earth’s surface
-75% of short wave radiation reaches the earth’s surface and converted to heat
-Re-radiation of longer-wave radiation is reflected back to Earth by greenhouse gases
A warm Earth emits long-wave radiations. The warm surface of the earth emits short wave radiation and then re-emits it as long waves (most of this long radiation is infrared or heat).
Greenhouse gases that retain the heat in the atmosphere absorb longer wave radiation. Greenhouse gases reabsorb longer-wave radiation, which retains the heat in the atmosphere. Between 70 to 85 percent of the long-wave radiation that is re-emitted is captured by the greenhouse gases, which effects as global warming. The band of wavelengths absorbed by individual gases such as water vapor, carbon dioxide, methane and nitrous oxide makes each of them a greenhouse gas.
Natural greenhouse gases are vital to the survival of life on earth. Carbon dioxide and water vapor are the most significant greenhouse gases
-Carbon dioxide
•Cell respiration
•Fossil fuel combustion
•Rain forest clearing & combustion
-Sinks of atmospheric CO2
•Photosynthesis, diffusion into aquatic systems, fossilization
-Return Carbon to lithosphere
•Decomposition of organic matter, marine deposits of carbonates
-Water vapor
•Formed by evaporation from oceans and transpiration in plants.
-Methane emissions
•agricultural rice paddy methanogen bacteria (emissions by intestinal methanogen bacteria in livestock)
•Extraction of fossil fuel
•Melting ice in polar regions
-Nitrogen oxides
•fossil fuel combustion
-Carbon dioxide
•Cell respiration
•Fossil fuel combustion
•Rain forest clearing & combustion
-Sinks of atmospheric CO2
•Photosynthesis, diffusion into aquatic systems, fossilization
-Return Carbon to lithosphere
•Decomposition of organic matter, marine deposits of carbonates
-Water vapor
•Formed by evaporation from oceans and transpiration in plants.
-Methane emissions
•agricultural rice paddy methanogen bacteria (emissions by intestinal methanogen bacteria in livestock)
•Extraction of fossil fuel
•Melting ice in polar regions
-Nitrogen oxides
•fossil fuel combustion
Global temperatures and climate patterns are influences by concentrations of greenhouse gases. After lines of ice form the Antarctic territory were analyzed, carbon dioxide bubbles presented patterns or rapid periods of warming with long cooling periods. These periods were examined, since phases of warming temperatures show high amounts of carbon dioxide and those cooling show low amounts of carbon dioxide. Temperature changes is the past 800,00 years have illustrated a pattern with the increase and decrease of carbon dioxide concentration.
Global temperatures and climate patterns are influenced by concentration of greenhouse gases.
-When the concentration of greenhouse gases increases, more heat will be retained and therefore this will result as an overall increase in global average temperatures.
-Higher temperatures also increase evaporation; causing longer periods of rain.
-Higher ocean temperatures can also cause a greater tendency of tropical storms and hurricanes.
-When the concentration of greenhouse gases increases, more heat will be retained and therefore this will result as an overall increase in global average temperatures.
-Higher temperatures also increase evaporation; causing longer periods of rain.
-Higher ocean temperatures can also cause a greater tendency of tropical storms and hurricanes.
There is a correlation between rising atmospheric concentrations of carbon dioxide since the start of the industrial revolution two hundred years ago and average global temperatures. During this phase, more countries became industrialized and combustion of coal, oil and natural gases increased rapidly; and as a consequence carbon dioxide concentration increased.
-The correlation between the industrial revolution, rising atmospheric carbon dioxide and higher temperatures is clearly marked.
-The correlation between the industrial revolution, rising atmospheric carbon dioxide and higher temperatures is clearly marked.
-Since 1800s humans have produced large quantities of carbon dioxide, and the level of carbon dioxide has increased by more than 35% compared with its pre-industrial revolution levels.
•Transport (car, trains, airplanes)
•Deforestation
•Heating homes
•Maintaining high meat diet
•Transport (car, trains, airplanes)
•Deforestation
•Heating homes
•Maintaining high meat diet
Recent increases in atmospheric carbon dioxide are largely due to increases in the combustion of fossilized organic matter. Burning fossil fuels have been a major contribution factor to a rise of carbon dioxide atmospheric concentrations.
4.3 carbon cycling
Carbon is one of the main elements found in all organic molecules including carbohydrate, protein and lipid.
Carbon exists in many forms:
-Atmospheric gas (CO2, CH4)
-Dissolved CO2 in oceans
-Organic carbon in living organisms
-Carbon deposits in lithosphere, as minerals or fossil fuels
Carbon exists in many forms:
-Atmospheric gas (CO2, CH4)
-Dissolved CO2 in oceans
-Organic carbon in living organisms
-Carbon deposits in lithosphere, as minerals or fossil fuels
Autotrophs convert carbon dioxide into carbohydrates, lipids and all other carbon compounds that they require. Carbon dioxide concentration in the atmosphere is currently around 0.039%.
In aquatic ecosystems, carbon is present as dissolved carbon dioxide and hydrogen carbonate ions. Carbon dioxide can either remain in the water as dissolved gas, or combine in the water with carbonic acid; reducing the Ph of the water.
Carbon dioxide diffuses from the atmosphere or water into autotrophs. The plants intake CO in order to create carbon compounds through photosynthesis. This then decreases the concentration of CO inside the autotrophs, and creates a concentration gradient between their cells and the airier water surrounding them.
-Land plants diffusion occurs through leaves
-Aquatic plants diffusion occurs through leaves or stem.
-Land plants diffusion occurs through leaves
-Aquatic plants diffusion occurs through leaves or stem.
Carbon dioxide is produced by respiration and diffuses out of organisms into water or the atmosphere. CO is a waste product of aerobic cell respiration, cells that provide this gas can be separated in three groups:
-Non-photosynthetic cells in producers, for example root cells in plants
-Animal cells
-Saprotrophs such as fungi that decompose dead organic matter
-Non-photosynthetic cells in producers, for example root cells in plants
-Animal cells
-Saprotrophs such as fungi that decompose dead organic matter
Methane is produced from organic matter in anaerobic conditions by methanogenic archaeans and some diffuse into the atmosphere or accumulates in the ground. Three different groups of anaerobic prokaryotes that are involved in methanogenesis are:
-Bacteria that converts organic matter into a mix of organic acid, alcohol hydrogen and carbon dioxide.
-Bacteria that uses the organic acid and alcohol to produce acetate, carbon dioxide and hydrogen.
-Archaeans that produce methane from carbon dioxide, hydrogen and acetate.
-Bacteria that converts organic matter into a mix of organic acid, alcohol hydrogen and carbon dioxide.
-Bacteria that uses the organic acid and alcohol to produce acetate, carbon dioxide and hydrogen.
-Archaeans that produce methane from carbon dioxide, hydrogen and acetate.
Archaeans carry out methanogenisis in environments such as:
-Mud along the shores and in the bed of lakes
-Wetlands where the soil or peat deposits are waterlogged
-Guts of termites and of ruminant mammals
-Landfill sites where organic matter is in wastes that have been buried
-Mud along the shores and in the bed of lakes
-Wetlands where the soil or peat deposits are waterlogged
-Guts of termites and of ruminant mammals
-Landfill sites where organic matter is in wastes that have been buried
Methane is oxidized to carbon dioxide and water in the atmosphere. Methane only stays in the atmosphere for up to 12 years and then oxidizes. Monatomic oxygen (O) and highly reactive radicals (OH*) are involved in methane oxidation.
Peat forms when organic matter is not fully decomposed because of anaerobic conditions in waterlogged coils. Saprotrophs use respiration to drain the water through cell respiration, as this is not all drained, dead organic matter is not fully decomposed.
Peat forms when organic matter is not fully decomposed because of anaerobic conditions in waterlogged coils. Saprotrophs use respiration to drain the water through cell respiration, as this is not all drained, dead organic matter is not fully decomposed.
Partially decomposed organic matter from past geological eras was converted into oil and gas in porous rocks or into coal.
-Coal is formed when deposits of peat are buried under other sediments, the peat is compressed and heated gradually turning into coal.
-Oil and natural gas are formed in the mud at the bottom of seas and lakes. Conditions are usually anaerobic and so decomposition is often incomplete.
-Coal is formed when deposits of peat are buried under other sediments, the peat is compressed and heated gradually turning into coal.
-Oil and natural gas are formed in the mud at the bottom of seas and lakes. Conditions are usually anaerobic and so decomposition is often incomplete.
Carbon dioxide is produced by the combustion of biomass and fossilized organic matter. If organic matter is heated to its ignition temperature in the presence of oxygen it will set light and burn. The oxidation that occurs are called combustion, complete combustion cause carbon dioxide and water.
Animals such as reef-building corals and mollusks have hard parts that are composed of calcium carbonate and can be fossilized in limestone. Animals that have hard body parts composed of calcium carbonate are:
-Mollusks shells contain calcium carbonate
-Hard corals that build reefs produce their exoskeletons by secreting calcium carbonate.
-Mollusks shells contain calcium carbonate
-Hard corals that build reefs produce their exoskeletons by secreting calcium carbonate.
C4 Conservation of biodiversity
Indicator species is an organism used to assess a specific environmental condition. An indicator species is an organism whose presence, absence or abundance reflects a specific environmental condition. (e.g. lichen or some macro invertebrates)
Relative numbers of indicator species can be used to calculate the value of a biotic index. The number of individuals of each indicator species is determined, each number is then multiplied by a pollution tolerance factor, and its weight average is determined.
In situ conservation may require active management of nature reserves or national parks. These conservation measures involve endangered species remaining in the habitat to which they are adapted. Establishment of nature reservers are sometimes not enough therefore active management must be implemented. This may involve:
-controlled grazing
-removal of shrubs and trees
-removal of alien species
-reintroduction of species that have been locally extinct
-re-wetting of wetlands
-limiting predators
-controlling poaching
-feeding the animals
-controlling access
-controlled grazing
-removal of shrubs and trees
-removal of alien species
-reintroduction of species that have been locally extinct
-re-wetting of wetlands
-limiting predators
-controlling poaching
-feeding the animals
-controlling access
Ex situ conservation is the preservation of species outside their natural habitat. Plant species can be grown in botanic gardens, or the seeds of plants can also be stored in banks of low temperatures. Animals on the other hand, can be dealt with captive breeding.
Richness and evenness are components of biodiversity.
Richness: number of different species present
Evenness: how close in numbers each species is to one another
Richness: number of different species present
Evenness: how close in numbers each species is to one another
Features that promote Biodiversity:
1. Large size vs. Small size:
-Large sites will avoid extinction with unexpected factors like fire or disease
-Large sites: more resources and breeding sites
2.Edge effect: boundaries between habitats or ecosystems
-At the edge of the forest, there is more sunlight, more wind and less moisture than at the center dec population on the edge
-Forest fragmentation
-Exception: Cow birds thrives at the edge where it lays its eggsinc Cow bird population
3. Corridors = used to connect isolated populations
- WWF established corridors between 40 isolated panda populations
1. Large size vs. Small size:
-Large sites will avoid extinction with unexpected factors like fire or disease
-Large sites: more resources and breeding sites
2.Edge effect: boundaries between habitats or ecosystems
-At the edge of the forest, there is more sunlight, more wind and less moisture than at the center dec population on the edge
-Forest fragmentation
-Exception: Cow birds thrives at the edge where it lays its eggsinc Cow bird population
3. Corridors = used to connect isolated populations
- WWF established corridors between 40 isolated panda populations