© T. M. Whitmore Last time: South Asia Geophysical Environmental regions Climate — key to life in...

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Last time: South Asia

•Geophysical Environmental regions Climate — key to life in S Asia

•Environmental problems & hazards

•Agriculture

Today: South Asia

•Green revolution & its impacts

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

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

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

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

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)

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

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)

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

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

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?

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

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

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

•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

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

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

Agriculture III

•Cattle — Sacred in Hindu India: > 200 million headTraction/powerDung Milk

© T. M. Whitmore Last time: South Asia Geophysical Environmental regions Climate — key to life in...

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