4.A food production impact on physical environment and people Flashcards
incentives to protect physical environment
- farmers aim to keep environment in equilibrium as its their livelihoods
- system to protect environment
- negative feedback: dairy farm -> manure is placed on fields from cows
impact on soil via food production
- wind and water erosion
- compaction via machinery and livestock
- cropping, declining organic matter
- salinisation
- desertification
- overgrazing
- over-cultivation
impact on biodiversity via food production
- declined because of monocultures
- deforestation = decline of biodiversity
impact on landscape via food production
- need for wetland drainage
- terracing of slopes
- deforestation - increasing field size
- monoculture eg wheat
- urbanisation - population increase = need for more food production and living
impact on water via food production
- depletion of water from over extraction
- pollution by agrochemicals and slurry via run off
- silting streams
impact on health via food production
- food shortages and surplus effect health adversely
- illness via chemical use
an impact of food production adversely affecting water
salinisation
salinisation
- result of water mismanagement
- land degradation in arid and semi-arid climates
- increase of salt in soil, brought to surface by evaporation and transpiration
- poor soil drainage bc of lack of precipitation
- salt layer poisonous to plants and inhibit water absorption
- salt = chloride, sulphate and carbonate
causes of salinisation
- water used to irrigate crops evaporates, capillary forces bring water to surface and deposits salt to surface
- costal areas: withdrawal of underground water for irrigation leads to the infiltration of marine and saline water into fresh water supplies
salinisation example
Aral Sea, Asia
- decrease in fertility
- volume of sea decreased by 90%
global governance - salinisation
- FAO, 20% irrigated land globally = decline in productivity
countries affected: Pakistan, China, USA and India
land-management solutions to salinisation
- avoid over-irrigation, use drip irrigation, soil moisture monitoring and water requirements
- crop selection: deep rooted to maximise water extraction
- less fallow periods
- crop rotations
- soil management
- biodiversity and land space maximised
- salt tolerant crops: sugar beet and barley
an impact of food production adversely affecting biodiversity
deforestation
deforestation
- clearance of forest in order ro gain agricultural land
- 13M ha of forest converted annually over 10 yr period to farmland
- pattern of net change in forests; net loss in Brazil and net gains in USA
impacts of deforestation from food production
- biodiversity decreased
- acquisition of agri-land, hedgerow removal, grazing and drainage of wetlands
- species are important to pollination, pest control and recycling of soil nutrients
deforestation in Brazil
- increase demand for soybeans = critical habitat decline
- deforestation increased x3
- soybean is leguminous allowing for crop rotations
- soybeans use: soy sauce, cooking oil, miso and soya milk (less calories more protein)
- threatens biodiversity of TR ecoregion
leguminous
nitrogen fixing plant
deforestation in Indonesia
- oil palm expansion = decreased of 700,000ha2 of TR in Malaysia
- Sumatra focus for cultivation - forest cleared via controlled forest fires = 80% decline in plant species
- loss of lowland forest in Riau and Tambi harbour endangered species
- land cultivation has expanded to national park buffer zone