Global interactions

environmental change

A word about the pictures• The pictures on these slides have been taken from various internet

sources. I haven’t asked for permission to use them, but this PowerPoint is for non-commercial educational purposes only and I therefore would like to thank you for your forbearance if you happen to find one of your pictures here.

Agro-industrialization

• Technology + cheaper transport = re-sourcing• Retailers and processors have increased

power• Affects LEDCs’ ability to compete• Modern farming methods impact

environment

Agro-industrialization

• Global farming increasingly intensive

• Subsidies partly to prevent farmers going out of business

• Farmers compete and increase efficiency– Labour saving machinery– Agro-chemicals (also

labour saving)– High yield varieties (HYVs)

Increased Yields

• In the last 50 years– Wheat yield increased

2.6 to 8 tonnes/Ha– Barley Yield increased

2.6 to 5.8 tonnes/Ha– Dairy cows – doubled

production of milk (now 5800 litres per year)

Methods and problems

• Animals reared on production lines– Results in increased

spread of disease• Vegetables sprayed with

pesticides– Apples average 17 times– Lettuce (imported)

average 11.7 times– Chemicals enter the

ecosystem

Environmental problems

• Costs for environmental restoration:• £2.3 billion per year ($4.4 billion, Kr 31 billion)– Cleaning up chemicals– Restoring habitats– Coping with sickness

• £200 million per year for water companies to remove pesticides and nitrates

• Just in the UK

Environmental problems• Air pollution and greenhouse gas

emissions• Costs UK £1.1 billion per year• 10% of UK emissions come from livestock

(methane) and fertilizers (nitrous oxide)• UK farmers have damaged ecosystems:

– 190,000 miles of hedgerow– 97% of meadows– 60% ancient woodland– 50% fall in farmland bird population

• Soil degradation• Increased flood risk (14% in some areas)

Water problems – Kenya, a case study

• Lake Naivasha (Kenya) loss of life and shoreland ecosystems

• Caused by– Pesticide pollution– Water extraction– Migrant worker

deforestation

Lake Naivasha today

Lake Naivasha

• Flower and vegetable growers blamed• Water diverted from rivers (remember the

Aral Sea?)• 12 flower firms remove 25% of river water

(enough for 100,000 small farmers)

Flowers• Supplied to UK and European markets• Flowers are 90% water• Exporting water = virtual water• Water exported from a dry to a wet region!• In direct competition to poor farmers and

pastoralists• Flower companies take both land and water

Virtual water import/export

Links• http://lakenaivasha.org/ (Lake Naivara)• http://www.fao.org/DOCREP/005/Y4383E/y4383e0d.htm (agroindustry

in Peru)• http://www.unescap.org/tid/publication/indpub2325_chap1.pdf

(economic effects of agro industry)• http://www.dpi.nsw.gov.au/agriculture/horticulture/floriculture/industry/

export#The-global-flower-trade (the global flower trade)

• http://www.google.se/imgres?imgurl=http://www.waterfootprint.org/WFP_files/Img/VWF_regionLrg.jpg&imgrefurl=http://www.waterfootprint.org/%3Fpage%3Dfiles/VirtualWaterFlows&usg=__86Wdki0ByJxNOMmRfTUG5Iy4hm4=&h=650&w=1270&sz=526&hl=sv&start=3&zoom=1&um=1&itbs=1&tbnid=9gjCJtzc4pwLbM:&tbnh=77&tbnw=150&prev=/images%3Fq%3Dvirtual%2Bwater%26um%3D1%26hl%3Dsv%26sa%3DX%26tbs%3Disch:1

(global virtual water trade)

Mining

Extraction of raw materials

Mined materials

• Metals (mined as ores)– Iron, copper, gold etc

• Industrial minerals– Lime (calcium oxide),

soda ash (sodium carbonate)

• Construction materials– Sand, gravel

• Energy materials– Coal, oil, gas

Impacts of mining

• Habitat destruction– Opencast mines– Disposal of waste rock– By-products of refining– Smelting

Impacts of mining

• Pollution– Extraction, e.g. mercury– Transport, emissions– Processing, e.g. Slag– Leaching of toxic by-products

• Land forms– Derelict land– Artificial hills– Physical and visual pollution

Increased air travel

• Transport produces 25% of global CO2 emissions

• Aviation accounts for 13% of transport emissions

• = total of between 2 and 3%• Shipping transport accounts for

22%• But aircraft are worse because:

Air transport emissions• Nitrogen oxides from exhausts help create ozone• Jet-trails = more clouds = intensified greenhouse

effect• Night-flights = increased condensation

(temperature difference) = more clouds than day-flights

• 25% of flights are night flights• But contribute 60 – 80% of contrail warming