Shifting cultivationShifting cultivation

Higher Rural GeographyHigher Rural Geography

IntroductionIntroduction

Shifting cultivation is now confined to Shifting cultivation is now confined to the humid tropics of South America, the humid tropics of South America, Africa and South East Asia.Africa and South East Asia.

It is estimated that shifting cultivation still supports between 300 – 500 million people.

Although there are changes taking place in the more accessible areas of the Amazon Basin, traditional shifting cultivation is still found in the more remote, and more thinly populated parts (e.g: Pastaza Province in eastern Equador)

Shifting Cultivation Vs Bush Fallowing

Shifting cultivation is when farmers move their home to farm new land.

Bush fallowing (e.g.: West Africa) is where only the clearings are ‘shifted’.

The amount of time an area of land is farmed for will depend on the rate of decline in soil fertility and the productivity of the clearings around it.

PopulationPopulation

In North Dakota, USA, where the population is 22, 000 people to 6000 km2.

In comparison, the Amazon Basin only has a few hundred people to the same area.

Low population is low due Low population is low due to a number of factorsto a number of factors

The areas is very isolated

Shifting cultivation is

unable to support a larger

population.

The road and communication network is

very poor

There is a lack of economic development

Disease is not a major factor in limiting the population (Although Malaria is endemic and measles,

whooping cough, influenza and chicken pox occur).

The Achuar people are a tribe of the Jivaro Indians.

There is a parallel drainage pattern which provide navigable waterways.

Settlement is dispersed and may range from 1 – 12 houses along the river bank.

http://www.treehugger.com/files/2007/08/zoe-tryon.php

IntroductionIntroduction

There is plenty of land for cultivation: it is an extensive system in which labour and output are relatively small in relation to the total area of land available.

Cultivation is aided by the year-long growing season, characteristic of the equatorial climate.

Characteristics of Characteristics of a a Equatorial Equatorial ClimateClimate

Precipitation: High, more than 2700mm during a year.

Temperature: Hot! Temperatures are high all year round. The average temperature is 26ºC.

Other Facts: Wild fruits grow between November and March.

Fact File:

40

35

3025

20

1510

50

-5-10

-15-20

-25

280

260

240220

200

180160140

120

100806040

200

J F M A M JJ A S O N D

Tem

pera

ture

in º

C

Precipitation in m

m

Month

Step 1 – With the help of stone axes and matches (low technology), the Jivaro Indians clear a small area of

about 1 hectare of forest.

Sometimes the largest trees are left standing to protect young crops from the suns heat and the heavy rain; so also are those which provide food, such as banana and

kola nut.

Step 2 - After being allowed to dry, the felled trees and undergrowth are burnt (slash & burn cultivation).

Advantages – weeds are removed and ash provides fertiliser.

Disadvantages – useful organic material and bacteria is destroyed.

Step 3 – The main crop manioc, is planted along with yams, pumpkins, beans and tobacco. The diet is supplemented by hunting (mainly for monkey), fishing and collecting fruit.

Manioc

Yams

The productivity of these ‘gardens’ can be very high, estimated as ranging from 2000 to over 20, 000 calories per day.

Step 4 - Once the forest has been cleared, the nutrient cycle is broken. The heavy afternoon, convectional rainstorms hit the

unprotected earth causing erosion and leaching.

With the source of humus removed, and the absence of fertiliser and animal manure, the ferralitic soils rapidly lose

their fertility.

Step 5 – Move on. Within 4 or 5 years, the decline in crop yields and the re-infestation of the area by weeds force the tribe to shift to another part of the forest.

Although shifting cultivation appears to be a wasteful use of land, it has no long-term adverse effect upon the environment. In most places humus can build up sufficiently to allow the land to be re-used within 25 years if necessary.

Changes in farming in the Changes in farming in the Amazon BasinAmazon Basin

Great population pressure and land-hunger in areas beyond the rain forest, (such as North East Brazil), have resulted in immigration by ’colonists’ on a large scale to take up holdings along new roads in the Amazon Basin.

Such colonists are from very different environments, and lack the knowledge and faming skills of the native peoples in sustainable land management.

The Amazon Rainforest has The Amazon Rainforest has been cleared for the following been cleared for the following reasons:reasons:

Thousands of kilometres of road have been built.

People have been given free or very cheap land to farm.

Cattle ranching is the most common type of farming requiring large areas of land.

Rivers have been dammed to make reservoirs & HEP stations.

Minerals have been extracted (eg: tin & iron ore)

Deforestation - BenefitsDeforestation - Benefits

Has enabled many people to move from areas suffering from drought, famine and overcrowding.

Has made it possible to mine valuable minerals that can then be exported.

HEP schemes have attracted industries which produce many jobs and save the country importing fossil fuels.

Timber can also be exported for profit.

Deforestation - ProblemsDeforestation - Problems

Problems

Fewer plants and less wildlife

Fuelshortages

Leachedsoil

Landslides

Fewer IndianTribes

Undrinkablemuddy water

SummarySummary

On a global scale, shifting cultivation is still a very important livelihood.

Globally, it is estimated that shifting cultivators clear between 20 and 60 million ha of forest and scrub each year, and then burn between 1 and 2 billion tonnes of dry matter, thus contributing to global air pollution.

Complete summary sheetComplete summary sheet

Resources:Resources: Core Geography p240-246Core Geography p240-246 Core Themes in Geography Human Core Themes in Geography Human

p40-43p40-43 Waugh p401-402Waugh p401-402

You have 20

minutes!

Your Your turnturn

Answer questions 9a, 9d, 10, 11 Answer questions 9a, 9d, 10, 11 on page 256 in Core Geography on page 256 in Core Geography

Resource: Core Geography pages Resource: Core Geography pages 240-246 240-246

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