topic 5 - soil Flashcards
what are layers of soil called?
horizons
what are the layers in order?
organic
surface layer
subsoil
substratum
bedrock
what features will change depending on which parent rock its made out of?
Depth
Texture
Drainage
Quality
Colour
soil forms by interactions of?
- lithosphere
- atmosphere
- hydrosphere
- biosphere
what can soil not be formed with out?
- lithosphere
- atmosphere
- hydrosphere
- biosphere
too much or little of one causes soil erosion
what is typical soil made up of?
50-60% mineral particles
1-5% organic matter forms humus when breaks down
40% pore spaces
what is precipitation effectiveness?
the balance between precipitation and evapotranspiration (water coming into soil through transpiration then lost bc of evaporation, the loss of water through soil pores)
what is a pedalfer?
soil that absorbs water from precipitation
what is a pedocal?
looses water
what are inputs into soil formation?
○ Organic material
○ Excretions
○ Precipitation
○ Solid particles and gases from atmosphere
○ Gases from respiration of plant roots
○ Mineral breakdown from parent rock
what are outputs in soil formation?
Nutrients taken up by plants
Nutrient leaching (flow of nutrients through rainfall
Soil erosion and mass movement (soil creep)
Evaporation
Heat
what are transformations?
change of state of matter or energy
what are the transformations in soil formation?
Decomposition
Weathering
Nutrient cycling
What are transfers in soil formation?
Water
Migration of organisms
Movement of biomass through trophic levels
whats a transfer?
Transfer is movement of matter or energy without a change of state
why has malnutrition decreased?
- education
- technology
- infrastructure (esp for agriculture)
- political reasons
what is food security?
being able to support the population with a stable food source
food availability?
sufficient food available on a consistent basis
food use?
appropriate use of food based on knowledge of nutrition?
what are the haves?
consist of countries that have enough cropland to feed their populations
what are the rich have-nots?
do not have sufficient cropland, however, can afford to import food to meet the deficient
what are the poor have-nots?
over 3 billion people live in these developing nations, which cannot produce enough food or purchase food for import
what is alpine transhumance farming?
○ Moving the cows around according to the different
○ Mobile land stock farming, based on seasonal movements
○ Predictable movements
○ Happens in Switzerland
what is slash-and-burn agriculture?
○ Forests are burned and cleared for planting
○ The ash provides some fertilization and it becomes relatively free of weeds
○ This is used for smallholder farmers in peru
Not sustainable after a few years then the land gets overrun with weeds
