Farming And Fertilisers Flashcards
(17 cards)
What is the problem with farming compared to natural ecosystems when it comes to recycling dead material?
Dead material in an ecosystem is digested and its nutrients are released into soil (for nutrient cycle)
But in farming the livestock for dead material is taken for slaughter and use it/crops harvested so nutrients from area are REMOVED
What is used to replenish lost nutrients from farming?
Fertilisers
What types of fertiliser are there?
Artificial
Natural
What are natural fertilisers?
Faeces and manure which contains nitrate and phosphate locked up in carbon compounds to supply lost nutrients from farming into the soil
What are artificial fertilisers?
Made by humans to contain phosphate and nitrate ions in the fertiliser
How does fertiliser help plant growth?
Supply the soil with nitrate and phosphate ions which can enter roots by active transport
Used to produce DNA/RNA (nitrate and phosphate)
Or proteins (nitrate)
Or ATP/ADP (phosphate)
Environmental issues of using fertiliser are…
Leeching
Eutrophication
Leeching
The process of nitrate and phosphate ions dissolve in water in soil
And move into nearby water bodies
What is eutrophication?
The result of leeching where there is a high concentration of phosphate and nitrate ions in water bodies
What happens following eutrophication?
An algal bloom grows on the surface of the water body
Why does algae grow on the surface of water?
Because they photosynthesise so need access to sunlight at the surface
What is the result of the algal bloom?
Plants below the surface can no longer photosynthesise as the algae blocks the light
So can no longer produce glucose so eventually die
Saprobionts will respire aerobically to decompose this, use up oxygen
So fish die as there is not enough oxygen dissolved in water for them to respire
2 ways farming practises aim to increase efficiency of energy transfer
simplifying food webs to reduce energy losses to non-human food chains
reducing respiratory losses within a human food chain eg reduce respiration that occurs in animals we eat
What reduces energy losses in non human food chains?
Pests that compete with us for food eg eat crops
Reduces energy transfer from crops to humans because some energy is transferred (in the form of NPP) to the pest instead
How to reduce energy losses by pests?
Kill them using insecticides = simplifies food webs to reduce the energy loss to non human food chains (pest food chain)
Pests
Any organism harmful to human or human activities (farming)
How to reduce respiratory losses in what we consume directly eg animals
Restrict animal movement so less respiration needed and less energy wasted
Keep animals warm indoors so less energy needs to be released by respiration for maintaining body temperature (e.g. less shivering)
