Ecology Flashcards
Name the 6 spheres of the earth system
Atmosphere(air)
Geosphere(land&solid earth)
Hydrosphere(water)
Cryosphere(ice)
Biosphere(life)
Antophopspeher(human life)
Explain what the geosphere is and the importance thereof
-It is the earth itself
- seems static but is highly active in all earth systems
- affects atmosphere and oceans including critical processes such as hydrological cycle and other biochemical cycles
-helps determine vegetation cover and related ecosystems
- is the key area where the carbon cycle takes place(eruption of volcanoes vent stored carbon to earths atmosphere as CO3) linking the geosphere, atmosphere hydrosphere and biosphere
Explain the atmosphere and the importance thereof
-A thin blanket of gas molecules separating earth from the cold vacuum of space
-heat trapping ability allows for life on earth to exist
- protects earth surface and organisms from harmful UV rays from the sun
- is dynamic and interacts with all the spheres
- allows for the transportation of air(wind) and the transportation of water(rainfall) critical processes of life in earth
Explain the hydrosphere and the importance thereof
-Is the sum of all water in earth and the hydrological cycle that distributes it around the planet
- is the main cause to why life flourishes on earth
- allows for the hydrological cycle to take place
Explain the cryosphere and the importance thereof
- is the total amount of frozen water around earth
- by means of volume constant ice retaining regions are dominated by ice sheets in Greenland and Antarctica
- ice and snow play a crucial role in the climate on earth
- causes sunlight reflection which is key to earths energy balance
- any change to permafrost( regions frozen for at least two years) could result in organic material frozen in ice to decompose changing the CO2 and methane balance in the atmosphere leading to global warming.
Explain the Biosphere and the importance thereof
-Made up out of various biomes containing many ecosystems
- each ecosystem containing specific species adapted to prevailing conditions
- energy from the sun ins captured by photosynthesising organisms know as autotrophs(producers) that use the suns energy to create and store nutrients
- these producers are then consumed by heterotrophs(consumers)
- each species specifically evolved to fill opportunities that were available
In what way is the biosphere changing ?
The collection of species on earth at any given time is constantly changing through the process of evolution
Explain the antroposphere and the importance thereof
-Is a subdivision of the biosphere
- focuses on human life and their impact on the environment via cultural, theological and built environment and associated activities on the planet.
- by harnessing the power of burning fossil fuels we have become the drivers in global change
- causing significant change to the biochemical cycles of nitrogen, carbon, phosphorus and sulphur cycles changing the climate and Ph of oceans earth
- humans chlorinated fluorocarbon(CFCs) have altered the ozone in the stratosphere
- carbon footprint can be seen across all spheres
How are the various ecological cycles linked ?
-Each cycle is unique although similar elements appear in more than one cycle
- both water and nitrogen are essential to life on earth and stay constant in their cycles
- water cycle is very dynamic and soil plays a key role in this cycle
- nitrogen from the nitrogen cycle must be broken down via bacteria(nitrogen fixing) in the soil for animals and plants before it can be used
- for the oxygen cycle photosynthesis is a key driver in this process and takes place explicitly in the biosphere.
- for the carbon cycle soil(biosphere) plays a key role in the sense that most carbon from the atmosphere comes from biological reactions with the soil
Fully explain the hydrological cycle
-Is a conceptual model that describes the storage and movement of water between the various spheres
- water stored in various reservoirs(atmosphere, oceans, lakes, rivers, glaciers, snowfields and groundwater) moves from one reservoir to another via processes like evaporation, condensation, disposition, perspiration.
- water evaporates mostly from the ocean to the atmosphere and gets redistributed mostly back into the ocean via perspiration but some over land masses
- imbalances corrected by runoff and groundwater back to the oceans
- the interdependence of continus movement of all forms of water provide the basis for the hydrological cycle
What happens to water that reaches the surface after perspiration?
One of three things:
- it may remain on the surface and get evaporated again into the atmosphere
- flow over the surface as overland flow and either enter streams, rivers and lakes where it will either get evaporated back into the atmosphere or where it will seep back to the ocean via groundwater or further surface flow.
- perspiration may flow in through gaps in the ground surface to join existing soil moisture. This will then either be evaporated back into the atmosphere eventually after it has been used by plants or it will be stored in groundwater and eventually get moved back via flow to the oceans
Explain the oxygen cycle in detail
-Is a complex cycle involving oxidative reactions with organic material components of the earths crust
- includes photosynthesis. Respiration, sunlight energy, weathering of rocks and volcanic eruptions
- oxygen is a by product of photosynthesis
- involved in the oxidation of carbs with the release of energy and CO2 and H2O
- primary role in biological oxidation is that it is a hydrogen acceptor
What hels the Oxygen cycle take place ?
The sun- suns rays give plants plankton and algae the ability to produce food(photosynthesis)
carbon dioxide in the air- used together with energy from the sun, water from soil to produce energy necessary for survival of all living things
photosynthesis-converts sunlight, water and carbon dioxide into food and oxygen
Allows CO2 in the atmosphere to remain constant
cellular respiration reverse process of photosynthesis, glucose converted to energy this breakdown involves oxygen and produces carbon dioxide and water
combustion - the burning of fossil fuels uses oxygen forms CO2 and H2O
Explain the carbon cycle in depth
-Ecosystems gain most of their C02 from the atmosphere
- abutotpohs are specially modified to absorb this and convert it to energy and O2
- C02 in the oceans enter via simple diffusion and are then converted to carbonate or bicarbonate which are used in further reactions
- when these organisms die carbon dioxide is released again
- stored in the lithosphere as inorganic and organic matter
Explain where carbon is stored in our planet
1) organic molecules in living and dead organisms in biosphere
2) as gas CO2 in the atmosphere
3) organic matter in the soil
4) in the lithosphere as fossil fuels and sedimentary rock
5) in the oceans as dissolved CO2 and calcium carbonate in the shells of marine life