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© T. M. Whitmore
Last time: South Asia
•Geophysical Environmental regions Climate — key to life in S Asia
•Environmental problems & hazards
•Agriculture
© T. M. Whitmore
Today: South Asia
•Green revolution & its impacts
© T. M. Whitmore
How does it work? •The “green revolution” consists of
several things — “the package”1) Dwarf, high yielding hybrid seeds (HYV)Response to fertilizerPhoto period insensitiveDwarf (less lodging; denser planting)
Genetic uniformity and so potential disease susceptibility
© T. M. Whitmore
How does it work? (continued)•“The package” continued
1) Dwarf, high yielding hybrid seeds (HYV)
2) Chemical Fertilizers (N-P-K)Nitrogen (N, often as ammonia); Potassium (K, commonly in a form called potash); & Phosphorus (P)
3) IrrigationNecessary to get the most out of fertilizers
4) Herbicides and pesticides 5) Often uses agricultural machinery
Pakistan – irrigated (dwarf HYV) wheat© 2005 The Great Mirror
Pakistan – irrigation technology© 2005 The Great Mirror
E India –mechanized rice harvest© 2005 The Great Mirror
© T. M. Whitmore
How does it work? (continued)
•Lacking the “package”: (hybrid seeds, water, fertilizer, and chemicals) Yields/ha are often NO better than
traditional varieties•Also needs infrastructure to develop and
sustain the technological packageRoads, markets, banking and finance,
rural credit, agricultural extension, research capacity, national integration and policy making
© T. M. Whitmore
Changes in an Punjab (India) village 1960s-1970s
•Changes are not just increases in output – the proportion of crops sown changesWheat:
yields up 2x as HYV monocrop increased proportion of village land
Riceyields increase 1970s as HYV monocrop
none planted in 1960s so increased % of village land
Maizeyields up as HYV monocrop increased proportion of village land
© T. M. Whitmore
Changes (continued)•Changes are not just increases in
output – the proportion of crops sown changes Cotton: no yield change; % downCane sugar: no yield change; %
downBersim (a form of clover):
legume/fodder crop for rotations little change in yielddecreased proportion of village land (stubble of maize/wheat used as fodder)
© T. M. Whitmore
Changes in technology• Irrigation:
increased for winter cropping; better tube wells and mechanical
pumps; costly, but worth it with higher yields
•Soil amendments: increased chemical inputs for rice,
wheat, maize; decreased intercropping and rotation
•Tools of cultivation: hand tools and oxen plows still; add some rental tractors
© T. M. Whitmore
Changes in technology (continued)
•Transport: ox carts & bicycles only before; better ox carts, motorbikes, some
trucks
•Use and type of animalsDecrease in cattle (traction)Increase in buffalo (traction AND
milk for local use and sale)
© M. Meade © M. Meade
© M. Meade
© T. M. Whitmore
Social Changes•Human populations
Total numbers grewProportions in upper classes lower
Many moved outor now manage larger farms; teach; etc.
Proportions in landless lower classes increased now wage labor
•Tenurenumber of holdings decreased - size of
some increased
© T. M. Whitmore
Social Changes (continued)•Public works
improved roadsimproved templelocal secondary school built
• Interconnectivity/dependenceRather self sufficient beforeNow reliant on
Capital (loans) Purchased inputsPetroleummarkets
•NotT clear that even though total output increased - wellbeing did for everyone
© M. Meade
© M. Meade
© T. M. Whitmore
South Asia & GR•Per hectare productivity up
Yet still below world’s best•Poor performance due to
Uncertain Monsoon and lack too little irrigation
•Tenure unevenMany very small holders =>Poverty
Cannot afford inputs•But, since late 1960s S Asia has been
able to feed itself – but for how long?
© T. M. Whitmore
Globally Problems & Successes
– critics and apologists•SuccessesImproved productivity 3-6 times as
much per hectareFar lower prices for main grain
crops world wideLower rates of extensification world
wideVastly increased food productionLower proportions of hunger and
lower absolute numbersRegionally variable
0
1
2
3
4
5
Yiel
d (m
etric
tons
/hec
tare
)
1960 1965 1970 1975 1980 1985 1990 1995 2000
Wheat Yield Rice Yield Maize Yield
Yields Are Up, But Growth is Slowing
World Resources Institute
© T. M. Whitmore
Problems with the technology itself
•Chemical pollutionrunoff can enter water tables and
poison local water sourcesindividual farmers often have very
little knowledge of risks using pesticides especially — thus compromising their health
© T. M. Whitmore
•Soil damagechemicals, especial herbicides and
other organic killers, can also kill micro organisms within the soils
very “tight” spacing of crops in the field lead to large demands on the soils for nutrients
tight spacing and mechanization can lead to soil compaction
Erosion & salinization
Problems with the technology itself
© T. M. Whitmore
Other Problems•Uneven geographic and crop-specific
impacts Little improvement in pulses and
rootsLittle improvement in crops that
are mostly un-irrigated (barley, millets, and sorghums)
•Regionally uneven•Most recent increase due to increase
in fertilizer not seeds per se
© T. M. Whitmore
Problems continued• Impacts on large and small holders
Difficult for poor to afford the “package”
Benefits of improved output mostly to the already relatively better off
•Other criticisms Genetic lossPetroleum dependence (fertilizer)Dependence on irrigationDoes not “solve” the food problem
© T. M. Whitmore
Agriculture III
•Cattle — Sacred in Hindu India: > 200 million headTraction/powerDung Milk
© John Wiley & Sons
N India –”Persian” wheel irrigation© 2005 The Great Mirror
© Pearson Education – Prentice Hall
N India – dung curing for fuel© 2005 The Great Mirror
© Michel Guntern