T4 (Water) Case Studies Flashcards
Irrigation Impact
USA
- irrigation depleting groundwater beyond natural recharge
- High Plains aquifer irrigates 20%+ USA cropland and close to depletion in Kansas as water level fallen a lot
- Texas: lowered water table 50m, large scale irrigation in semi-arid area linked to rainfall increase, hail storms and tornadoes
Pakistan, Indus Plain: water table raised 6m = salinisation
Ocean Circulatory Currents
- Gulf Stream (warm) - transports from Gulf of Mexico to NW Europe
- Great Ocean Conveyor Belt
World Water Gap
- 1.4bn lack clean drinking water
- 2.4bn lack adequate sanitation
- By 2025 population growth demand 20% more water
- 12% consume 80% water
Economic Water Scarcity
Bolivia (South America’s poorest country)
- La Pez = 3,500m asl, pop 200,000, over 1/4 homes don’t have access to safe, running water due to privatisation of water company (free market brutality)
- Many lack steady work = can’t afford water (have to create wells and sewage holes = contamination and illness
- Area plundered for resources (silver mines) = land exploitation for few rich (poor no benefits of wealth) - vast gas reserves now found - gas and oil privatised (taxes slashed to attract TNCs) - Spanish oil company earn 10x invested originally
- 2003 protests met with army - massacre (people don’t want TNC control (anti-globalisation)) = 100 suffered bullet wounds, over 20 snipers caused death and injury
- World Bank refused to guarantee loan for local water programme = forced to sell water systems (privitisation) = v high water prices
- military back TNCs - even rainwater privatised (illegal to collect)
Water Consumption by Industry (LEDC/MEDC)
LEDCs agriculture = 82% water consumption globally
MEDCs Industry = 59% water consumption globally
Conflict arising from shared water Resources
The Nile Basin
- 11 countries in Nile Basin depend heavily on the river
- 450mn ppl in Nile basin countries, over 200mn rely directly on the Nile (pop expected to double in 25yrs)
- 1929 treaty Egypt and Britain’s East African Colonies awarded 57% waters to egypt and restricted water projects on river by other countries
- 1959 Egypt and Sudan Nile Water agreement - Egypt 3/4 water, Sudan 1/4 - did not consult Ethiopia = the rivers main source, Egypt and Sudan built mega dams for irrigation purposes
- Upstream Nile Basin countries started negotiations 1999 = 2010 Entebbe Agreement for equitable water share but Egypt and Sudan rejected this - in effect as international law however in 2011 = all countries allowed water projects
- Egypt vulnerable as 97% water needs met by Nile
- Ethiopia Great Ethiopian Renaissance Dam plans 2011 (6000 megawatts electricity producer) - Egypt demanded suspension of plan 2014 (ignored) - US$4.2bn mega dam caused protest as fear reduce flows downstream (in Egypt)
- Environmental Pressures worsen this conflict!
Technological Developments in Fishing
Northern European mackerel and herring fleets use sonar techniques to find fish - allows targeting only herring when in season, avoiding other fish - contributed to herring fishing’s Marine Stewardship Council certification as sustainable and well-managed fishery
Fishing Success
EU-wide ban on discarding - end wasteful practice of discarding over-quota, undersize and low-value fish
Over-fished fish stock to point of collapse
Grand Banks (off Newfoundland)
- Once world’s richest fishery
- 1992 closed to allow stocks to recover
- expected closure 3yrs but fish numbers (cod especially) not recovered = still closed
- Cod’s niche taken by other species e.g. shrimp and langoustines (langoustine stocks previously kept low as youngsters predated by mature cod now reserve = young cod and eggs predated by mature langoustine)
Rice-Fish Farming (Intensive Subsistence Farming)
Thailand
- Cultivating rice and fish together = tradition 2000+yrs
- Polyculture system (paddy rice fields stocked with fish) abandoned (pop pressure and decreasing wild fish stocks) then revived 1990s due to concerns with pesticide use in high-yield rice monoculture
- Inexpensive and low risk
- Farmers dig small ponds/trenches in low-lying areas of rice which become refuges for fish (excavated soil used to raise banks for other crops)
- Paddy fields flooded and young fish introduced to trenches
- After 3 weeks (rice established) fish let into rice fields - obtain food from field
- Fish = decrease disease and pest incidence in rice
- fertilisers not needed (fish faeces naturally fertilise soil)
- Rice-fish culture increase rice yields up to 10%, increase income 50-100% over rice alone while providing protein source (fish)
- Common carp and Nile tilapia most commonly used fish (feed on vegetation/plankton available and not attack other fish)
- low cost feeding fish, high labour demands, low technology
- irrigation water and breeding stock cost
- output high per hectare, low per farmer
- high overall efficiency
- low environmental impacts (but change in nutrient balance, introduction alien species)
- Cultural issues = other fish preferred / species used not valued
- only appropriate if reliable water supply, source of young fish, fields close to farmers home
Whaling Committee
- 1930s over 50,000 whales killed annually
- International Whaling Commission (IWC) 1986 ban on commercial whaling
(- Southern Ocean around Antarctica declared a whale sanctuary 1994)
Inuit and Whaling Case Studies
- North America / Alaska
- Bowhead whale hunted; whaling central part of Inuit culture and protein in diet
- 10,000 inuits Alaska allowed to kill up to 336 bowhead whales between 2013-18 with no more than 67 whales in one year
- whales = 50% meat Inuit diet - Greenland
- Inuit whalers catch 175 whales annually
- IWC allows more densely populated west coast to take over 90% catch
Whaling
Japan
- Great hunter of whales
- reluctantly stopped commercial hunting 1986
- continued to hunt whales for ‘scientific research’ of populations
- clashed with Australia and Western countries who oppose whaling on conservation grounds
- Australia took case to UN’s International Court of Justice, argued Japan’s scientific research whaling programme = commercial whaling in disguise - Japan claimed whaling sustainable, Australia attempting to impose its cultural norms
- 2014 UN ruled Japanese Gov must halt its whaling programme in Antarctic - believed not for scientific research as Tokyo claimed - claimed Japan caught 3600 minke whales since programme start 2005 with limited scientific output - Japan agreed to abide but disappointed
Water Pollution
China
- 2014 60% underground water polluted
- Of 4778 testing spots in 203 cities, 44% had ‘relatively poor’ underground water quality
- Gov only just addressing environmental impacts of its development model - limited info on water pollution
- 2013 1/3 water resources were groundwater based, only 3% urban groundwater was clean
- 70% groundwater in north China plain (400,000km2) unfit for human consumption
- Most civilians boil or buy bottled water as tap water unsafe to drink
- 2014 chemical spill poisoned water supply of Lanzhou (NW China city with 2mn people)
- Beijing’s annual per capita water availability = 120 cubic metres (1/5 of the UN’s cut-off line for ‘absolute scarcity)
Indicator Species Examples
- Tubifex Worms (pop increase downstream of effluent entry - high pop in river = organic pollution recently occurred)
- Stonefly nymphs (pop crash when effluent enters habitat - need clean water - absence = organic pollution, large pop = clean, unpolluted water)