9 - Ecosystems - Cycles Flashcards
What are the 4 stages of the Water Cycle?
- Evaporation
- Transpiration
- Condensation
- Precipitation
What happens (briefly) at each stage of the water cycle?
E - Sun makes land water evaporate into vapour
T - Plant water also into vapour
C - Warm vapour carried up, cools/condenses into cloud
P - Water fall as precipitation; fresh land water
P - Water drains into sea, cycle again
Why is the Water Cycle so important?
- The water is constantly recycled
- If it wasn’t we’d run out quickly, meaning everything would die as everything needs water to live
How can thermal desalination be used to create potable water?
- Desalination removes salts from salt water (like sea)
- One method is thermal desalination:
- Salt water is boiled in a large vessel till it evaporates
- Steam rises, salts stay at the bottom
- Steam travels down a pipe … cools & condenses into pure water
How is reverse osmosis used in desalination?
- Osmosis here moves water from a lower salt conc to higher salt conc
- Reverse osmosis is the opposite & is used to rid impurities in water:
- Salt water treated to remove solids, then fed at high pressure to a vessel containing partially permeable membrane
- Pressure makes water move in opposite direction to osmosis - high to low
- Salts left behind as water forced through
What is a drought?
- Drougts occur when there isn’t enough precipitation
- Causes issues as we rely on precipitation for fresh water for drinking
- However, alternative methods exist for making potable water, like desalination
How can farmers increase the amount of nitrates in soil with crop rotation?
- Crops take up nitrates from the soil to grow, meaning overtime nitrogen content in soil decreases
- Instead of growing the same crop in a field year after year, different crops are grown in a cycle
- Cycle usually includes a nitrogen fixing crop to return nitrates to the soil for another plant to use next year
How can farmers increase the amount of nitrates in soil with fertilisers?
- Spreading animal waste/compost recycles the nutrients left in that waste & returns to the soil through decomposition
- Artificial fertiliers can also be used, though expensive and can cause environment issues
What are the 4 different types of bacteria involved in the nitrogen cycle?
- Decomposers
- Nitrifying Bacteria
- Nitrogen-Fixing Bacteria
- Denitrifying Bacteria
What is the role of Decomposers in the Nitrogen Cycle?
Decompose protein & urea, turns into ammonia
- Ammonia forms ammonia ions which plants can use
What is the role of Nitrifying bacteria in the nitrogen cycle?
Turns ammonia in decaying matter into nitrItes and then nitrAtes
- Diff species of nitrifying bacteria are responsible for making nitrites/nitrates
A ) Explain the importance of decomposition in the carbon cycle B ) What are the 4 organic compounds in the processes involved
A ) - Done by microorganisms which require oxygen & produce CO2 gas, H2O and lots of thermal energy
B ) Consumers, Green Plants, Dead Organisms, Fossil Fuels
Why are
A ) Consumers
B ) Green Plants
important to the carbon cycle?
A ) Respiration returns CO2 to the atmosphere or ait which is dissolved in water, mainly oceans. Increases CO2
B ) Feeds consumers, does photosynthesis which removes CO2 & respiration which returns CO2
How are
A ) Dead Organisms
B ) Fossil Fuels
involved in the carbon cycle?
A ) They fossilise, storing CO2 for a long time. During decay & decomp, CO2 is released as microorganisms respire
B ) Come from fossilisation of dead animals. Combustion & burning them releases CO2
What is the role of Nitrogen-Fixing bacteria in the nitrogen cycle?
Turn atmospheric nitrogen into ammonia, which forms ammonia ions
