(a)1.65 t/ha(b)490 mm(c)too much water rots the

plant• inadequate aeration•nutrient deficiency• toxic concentration of some

element

CountryCultivated landunder irrigation

(%)Rank (X)

Total foodproductionfrom irrigatedland (%)

Rank (Y)Deviation(X-Y)

(X-Y)2

India 30 6 50 6 0 0Pakistan 65 1 80 1 0 0China 50 2 70 2 0 0Indonesia 40 3 60 3 0 0Chile 36 4 55 5 -1 1Peru 35 5 56 4 1 1Mexico 25 7 40 7 0 0

Total 2

)1(

)(61

2

2

nn

YXcorelation rank sSpearman'

964.0)149(7

261

corelation rank sSpearman'

strong / high positive correlation

It means that a higher percentage of cultivated land under irrigation will most probably lead to higher percentage of total food production from irrigated land

• Adding water provides optimal conditions for plant growth;

• Adding water extends growing season;• Irrigation may permit more than one crop per

year;• Stable water supply provides stable yield;• Irrigation may increase the intensity of land

use• Irrigation may allow the introduction of high

yielding variety

Method Eff ectiveness Constrains

Mechanization

Laboursaving/ f ree f romshortage of labour

Free f romexpensive labour

Higher effi ciency Higher

productivity

Greater capital isneeded

Not suitable tosmall f arm sizeand f ragmentedfarmland

The educationlevel andtechnology off armers shouldhigher

Method Eff ectiveness Constrains

Applicationof chemicalf ertilizers

I ncreaseproductivity/higher yield perhectares

I ncrease thefarming intensity

I ncrease thenumber of croppingper year

Encourage theadoption of high-yielding varieties

Pollution Aff ects soil

structure andleads to soilerosion

Expensive / mayleads to loss off oreign exchange

The educationlevel andtechnology off armers shouldhigher

Method Eff ectiveness

Constrains

Applicationofpesticides

Reduceloss f rompests

I ncreaseproductivity

Expensive / may leads toloss of f oreign exchange

The education level andtechnology of f armersshould higher

Dangerous and toxic toman

Pollution Resistance level of pest

develops very quickly Food chain contamination

Method Eff ectiveness Constrains

I ntroduction ofhigh-yieldingvarieties

High yielding /higherproductivity

Greateradaptability

Greaterresistance

Shorter lif ecycle

More chemicalf ertilizer, pesticidesand irrigation waterare needed

Huge capital isneeded

High education leveland technology isneeded

Foreign / governmentaids is needed

Method Eff ectiveness Constrains

Landreform

Tenant f armers canhave their own land

High incentive toimprove f armingmethod

Consolidation of f armreducesf ragmentation

The interest oflandlords would beaff ected, therefore,political and socialdispute may beresulted

A strong centralgovernment isneeded

Provisionof credit

Provide adequatecapital to small f armers

Encourage f armers toadopt new technology

Largefi nancial burdento government

I mprovement oftransportf acilities

Help f armers to exporttheir products to market

Encourage theproduction of cash crop/commercial

f arming I ncrease the income of

the f armers

Huge capitalis needed

Consequence of Green Revolution in developing countriespolarization of society high yields do not always mean high

return for the farmers because prices may be lowered. Thus income is not guaranteed. Those who benefit most are : government bureaucrats (from corruption), international companies (from selling factors of production), landlords (from controlling more land and exporting more farm products),

and industrialist (from lower wages due to more abundant supply of food). Investment Is always concentrated on the land controlled by landlords

many farmers do not want to risk bad harvest. Some are too conservative to try new crops

many owner-occupiers suffer from bankruptcy when they are unable to re-pay their debts.

As a result, they have to sell their land, always at much lower prices, to landlords, and they become farm labourers or tenants

in order to minimize cost and avoid crop-sharing with the tenants, landlords always introduce mechanization to their farms. They may stop renting their lands and start large-scale commercial farming by employing farm labourers

higher productivity will result in higher land price, it will result in higher rents for tenants, higher taxes for owner-occupiers and attract speculation on land (by both landlords and capitalists from the city)

• food supply to the rural population disturbed as owner-occupiers and tenants lose their farms, crop-sharing replaced by cash tenancy and farming becomes export-oriented, with the choice of crop depending on external demand

agricultural production, export and GNP of the country may be higher, but there would be a tremendous loss in foreign currency due to the import of machines, seeds, chemical fertilizers and pesticides

locally developed hybrids are always neglected, but they are always more adaptable to the local environment than the imported ones

• good farming practices for soil conservation are neglected, and are replaced by increasing application and reliance on chemicals

Nucleated Pattern

Clustered Pattern

Disperse Pattern

Linear Pattern

na

0.5

D(obs)Rn

Nearest Neighbour Analysis

Rn is the nearest neighbour valueD(obs) is the average of all the distance between the settlements (points) and the nearest settlement (neighbour) to these settlements (points)A is the area under study (km2)N is the total number of settlements (points)

If D(obs)=0

Rn=0

All points aggregate/cluster together.

If

Rn=1

Random distribution

If

Rn=2.15

Regular distribution