4.A food production impact on physical environment and people

Question 1

incentives to protect physical environment

Answer 1

• 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

Question 2

impact on soil via food production

Answer 2

• wind and water erosion
• compaction via machinery and livestock
• cropping, declining organic matter
• salinisation
• desertification
• overgrazing
• over-cultivation

Question 3

impact on biodiversity via food production

Answer 3

• declined because of monocultures

- deforestation = decline of biodiversity

Question 4

impact on landscape via food production

Answer 4

• need for wetland drainage
• terracing of slopes
• deforestation - increasing field size
• monoculture eg wheat
• urbanisation - population increase = need for more food production and living

Question 5

impact on water via food production

Answer 5

• depletion of water from over extraction
• pollution by agrochemicals and slurry via run off
• silting streams

Question 6

impact on health via food production

Answer 6

• food shortages and surplus effect health adversely

- illness via chemical use

Question 7

an impact of food production adversely affecting water

Answer 7

salinisation

Question 8

salinisation

Answer 8

• 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

Question 9

causes of salinisation

Answer 9

• 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

Question 10

salinisation example

Answer 10

Aral Sea, Asia

• decrease in fertility
• volume of sea decreased by 90%

Question 11

global governance - salinisation

Answer 11

• FAO, 20% irrigated land globally = decline in productivity
  countries affected: Pakistan, China, USA and India

Question 12

land-management solutions to salinisation

Answer 12

• 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

Question 13

an impact of food production adversely affecting biodiversity

Answer 13

deforestation

Question 14

deforestation

Answer 14

• 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

Question 15

impacts of deforestation from food production

Answer 15

• 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

Question 16

deforestation in Brazil

Answer 16

• 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

Question 17

leguminous

Answer 17

nitrogen fixing plant

Question 18

deforestation in Indonesia

Answer 18

• 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