agriculture

three key principles of agriculture

1 selection of species

2 control of biotic and abiotic factors to control population

3 manipulation of food species to improve productivity

selection of species depends on 3 things-

1 market demand and access

2 if environmental conditions re in rot of food species

3 if environmental conditions or species adaptions can be controlled to improve productivity

how does high temperature affect biochemical reactions

increase their rate

what is the use of thermoregulation in mammals and birds

keep their bodies warm

reduce heat loss

increase amount of energy in food growth

why are frost free periods important

some crops are damaged by frost eg maize and fruit blossom

how does higher temperature affect evapotrasnpiration

higher temp= higher rate = more water needed for crops

why are low lying areas more likely to have frost

cold air condenses there

why do south facing slopes in the north hemisphere and north facing slopes in the south hemisphere tend to be warmer

receive more insulation

where crops are sufficiently valuable how can temperature be raised

greenhouses via solar heating or burning gas eg paraffin

impacts of frosts in orchards

destroy flowers

stop crop production

how are frosts prevented in orchards

burning gas and oil

what does placing transparent plastic cloth over fields do

retain warm air close to ground and protect crop seedlings

how can livestock be kept warm

providing shelter or buildings that are already heated