Food and Land Part 1 Flashcards
what is an organism?
individual living thing: reacts, grows, reproduces, maintains homeostasis
Eg. plant, animal, virus?, bacterium, fungus
what is an ecosystem?
Interrelationships between environment and living organisms; energy flow
what is wildlife?
undomesticated species, not plants
Housecat not wildlife, tiger, wildlife
what are the 5 environmental affects of food/fibre production.
- soil
- biodiversity loss
- air pollution
- water
- human health
what is soil?
- Mixture of eroded rock, organic matter, nutrients, water, air, living organisms (mostly detritivores)
- Potentially renewable resource
- Filtres and holds water
- Slowly renewed
- Varying levels of maturity
what are soil horizons?
Distinct texture and composition; differs with soil type
what is a mature soil?
has at least 3 horizons
what are the different soil horizons
O horizon
A horizon
B horizon
C horizon
Explain the O horizon?
layer you would see when you look down on non-degraded soil
O stands for organic, leaves and dead organisms, and anything organic “leaf litter”
Major input of nutrients happens, without layer no nutrients in soil
explain A horizon
Topsoil
Essential for food growth
Majority of where roots are
Where organic material is pulled down in layer
Tree roots will go down a little further, most roots in A layer
Most of the nutrients are stored here, where organisms live
Humus - Organic material that has started to breakdown
explain B horizon?
Less organic material
Fewer organisms
Because organic stuff is food for organisms
Larger tree roots, some “parent material” exist
explain c horizon?
Rock that establishes that area
what are the 5 soil types?
- Deciduous forest soil
- Coniferous forest soil
- Tropical rain forest soil
- Grassland soil
- Desert Soil
Explain deciduous forest soil?
Large topsoil, well developed A horizon
We have seasons so every single year on so we have a large input of organic material, large O input, so organic material is food for organism and makes conditions ideal for organisms
Temperature as well creates this well developed A horizon
C horizon there, but broken down significantly over time
explain coniferous forest soil
Acidic litter from pine needles
Acidic conditions not ideal for organic material and organisms
Less well developed A horizon
Acidic, colder, less precipitation
C layer is more prominent, some places all you see is rock or parent material
Not mature if it doesn’t have 3 layers
explain tropical rain forest soil?
In tropical forest soil, most of the nutrients are higher because growth is so fast they take up all the nutrients, all of the organic material that falls to the ground gets taken up or washed away by high rain fall
Nutrients mostly contained by tree canopy, not in the soil
Has consequences when we deforest a place and try to grow food
explain grassland soil?
Similar to deciduous forest
Well developed A horizon
In grassland system, constant input generating organic input, highly productive system
Grass blades are really easy to break down for organisms
Leaves not as easy
explain dessert soil?
Looks the way it does because of very little precipitation
Hot, dry
If there’s no food there are no organisms, reason there’s so little organic material because whatever’s growing there doesn’t want to lose pieces of itself because conditions are so harsh for it to grow
what are levels of the foodchain called?
trophic levels
how many trophic levels are there?
4
what are the 4 trophic levels?
producers, primary/secondary/tertiary consumers
what is the 1st trophic level?
producers - autotrophs, Organisms that photosynthesize
Can take solar energy and convert it to chemical energy
explain the 2nd trophic level?
primary consumers - herbivores, Don’t produce consume first trophic level
explain the 3rd trophic level?
secondary consumers - carnivores
explain 4th trophic level?
tertiary consumers - top carnivores, humans eat at every level
explain detritivores?
Eat whatever is recycled, vultures
what is a food chain?
Sequence of who eats or decomposes whom in a system
Determines how energy moves through system
explain primary productivity?
Energy available from primary producers = primary productivity
Chemical energy is transferred through the pyramid
what are the two types of producer productivity?
- Gross primary productivity (GPP)
2. Net primary productivity (NPP) (most important)
explain gross primary productivity?
rate at which producers convert solar energy into chemical energy as biomass
explain net primary productivity?
rate at which new energy is made by producers and available for use by consumers
why is net primary productivity essential to life?
Our lives depend on NPP
Directly or indirectly destruction of NPP impacts us
what are the 2 major types of agriculture?
- Industrialized (high-input)
2. Traditional
explain industrialized agriculture?
Where we get most of our food
Plantation – tropical developed countries
High inputs of water, pesticides, fertilizers etc.
A lot of highly mechanized inputs
explain traditional agriculture?
Feeding limited number of people
what are the two types of traditional agriculture?
- Subsistence agriculture
Human labour, some animals; survival - Intensive agriculture
Increased inputs; survival and income
what are different techniques used in agriculture?
interplanting - several strategies: Polyvarietal cultivation Polyculture Intercropping; companion Agroforesty (a.k.a.alley cropping)
