RURAL GEOGRAPHY
Global Agricultural Systems
Agriculture
• Part of a complex system
• Operates at different levels of intensity in different
parts of the world, and for different purposes
• Interaction of hydrosphere, atmosphere and
biosphere, human and economic factors
• Has changed, and continues to change, as a result
of developing technologies, especially the Green
Revolution of the latter 20th century
• Different types of agriculture have distinctive human
landscape with its own pattern of settlement and
communications; characteristic population density,
structure and distribution.
GMTs
Analysis of:
• Land use data and crop yield in map and
diagrammatic form
• The results of farm surveys
• Annotation of field sketches and
photographs of rural landscapes
Types of Agriculture
•
Arable farming = crops
– Most favourable areas in terms of relief, soil
and climate.
•
Pastoral farming = livestock
– Response to difficult conditions in terms of
height, slope and rainfall (both high and low)
•
Mixed farming = crops + livestock
Types of Agriculture
•
Subsistence farming = to feed local people
without having a surplus
–
•
May lack capital and modern technology, but
methods involve high degree of skill and ingenuity.
2.Commercial farming = to produce surplus for
sale, either locally or distant
–
Capital intensive, dependent upon technology
(mechanical, chemical + biological) and dependent
on efficient transport links
Types of Agriculture
•
Shifting cultivation (usually subsistence)
– Low population density, therefore low
demand for food; must be plenty of land
available to allow people to move cultivated
plots and settlements as necessary.
•
Sedentary cultivation (usually small/
large scale commercial)
– Permanent cultivated land and settlements
Types of Agriculture
•
Intensive agriculture
– High level of capital and artificial inputs
(fertiliser, pesticides) resulting in high yields
– e.g. battery poultry units/ dairy farming
•
Extensive agriculture
– Low level of capital and artificial inputs
resulting in lower yield, but often involving
large areas of farmed land.
– e.g. large grain farm/ cattle ranching
Farm System
1
•
•
•
2
3
•
•
•
INPUTS
Physical
Human/ cultural
Economic/ political
DECISIONS
OUTPUTS
Profit
Stability
Loss
Lack of
investment
and stagnation
Question
CORE HIGHER
PAGE 255
QUESTION 1
Diagram 8.5 is on page 233
SHIFTING CULTIVATION
SHIFTING CULTIVATION
• Example of Extensive Subsistence
Agriculture
• Found in areas with low population
densities
• Humid tropics of South America, Africa
and South East Asia
• Globally supports as many as 300 million
people
Shifting Cultivation Characteristics
(summarise in spider diagram)
• Settlement usually small and temporary
• Settlement lifespan is determined by the rate of decline
in soil fertility and the productivity of the cultivated
clearings around it
• Remote areas, and thinly populated areas of Amazon
Basin
• Low population densities because of
• Isolation, poor communications and lack of economic
development
• The inability of shifting cultivation to support a larger
population; once the population reaches its threshold a
small “break off” group will set up a new group
Shifting cultivation and low
population densities
Shifting Cultivation Characteristics
• Core Higher, Page 242, Diagram 8.18
• Draw and annotate field sketch of typical
single house settlement
• Remember the title
Shifting Cultivation
• Extensive system – large land area available, low input of
labour and low output
• Year long growing season helps cultivation
– (Fig 8.21, Page 243)
• “gardens” of cultivated land around traditional single house
• Crops include manioc, bananas, yams (high carbohydrate)
• Sustainable form of agriculture, although it requires large
amounts of land to make it possible. Is it sustainable
globally when it involves the destruction of primary
rainforest??
• Best cultivated with less than 8 crops for 2yrs then left
fallow (unused) for 10yrs during which time it will revert to
secondary rainforest and the soils recover fertility.
• If no new land is available, or the population increases, the
“garden” can be continuously cultivated but requires
frequent applications of fertiliser.
Shifting Cultivation
The Clearing Process
• Un-cleared rainforest floor has thick humus layer with
rapid organic decomposition
• Slash and burn cultivation – vegetation slashed and
cleared using machetes, then burned to finally clear area
and also to enrich soil by input of phosphorus and
potassium from burning the vegetation.
• However, the soils (latisols) are basically of low fertility
and when rainforest is cleared the soils are left open to
high rainfall
• Nutrients are leached down through the soils
• Soil fertility is reduced
• Productivity is reduced
• Garden is abandoned
• New clearing is made in a new part of the forest and the
process begins again.
Abandoned clearing
Current clearing
(reverting to secondary
rainforest)
Virgin Rainforest
Pressure on Shifting Cultivation in
The Amazon
1. Figure 8.25, page 245
Discuss sustainability
Question 11, page 256,
2. Read page 245
Create a spider diagram detailing the main
threats and pressures on traditional shifting
cultivation practices
Extensive areas of rainforest
cleared for large scale cattle
ranching to provide beef for
huge urban population of SE
Brazil
Extensive areas of rainforest
cleared for mineral (iron ore,
gold, copper, bauxite) and
timber resource exploitation
Pressure on Shifting Cultivation in
The Amazon
Population pressure in , for example,
NE Brazil results in immigration by
“colonists” on a large scale to take up
holdings along new roads within the
Amazon Basin. These colonists
come from different environments and
lack the knowledge of the native
people in farming in a sustainable
way so ever increasing amounts of
land need to be cleared
Extensive areas of
rainforest cleared
for large scale
Hydro Electric
schemes to provide
power
eg Tucuri Dam
Project, Brazil
Clear felling of large areas of
rainforest for heavily fertilised,
single crop agriculture rather
than sustainable “gardens” of
traditional shifting cultivation.
As soil productivity decreases
more and more land has to be
cleared.
RICE CULTIVATION IN KEDAH
STATE, MALAYSIA
• Example of Intensive Peasant Agriculture
• Very high population densities (low death rate, high life
expectancy)
• Humid tropics of South East Asia
• Traditionally subsistence agriculture but recent changes
have led to increasing yields and have changed system
to commercial agriculture
• Small holdings as land is at a premium, only one-two
hectares often in scattered plots often some distance
away from kampoongs (villages either along
embankments or on islands within padis)
(Figure 8.28, page 248)
RICE CULTIVATION IN KEDAH STATE, MALAYSIA
REQUIREMENTS FOR CULTIVATION
• All year round growing season – equatorial climate with
monsoon influence provides a wet season in which rice grows
and a dry season in which it ripens and can be harvested.
• High temperatures and small temperature range (difference
between highest and lowest temperature)
(Figure 8.30, Page 250)
• Flooded padi fields or sawahs to grow rice
• Dry months of January and February allow padi fields to dry
out and rice to ripen
• Irrigation from Muda Irrigation Project allows padi fields to be
flooded during dry season and allows two rice crops per year
to be grown under more intensive modern cultivation.
CLIMATE OF TRADITIONAL RICE CULTIVATION
Traditional
one crop per
year
cultivation –
New rice
breeds allow
two crops per
year
nowdadays
Bunds – small raised
earth walls –
between padis
Transplanting rice plants
by hand into flooded padi
fields
Transplanting rice plants
by hand into flooded padi
fields
Growing rice in flooded
padi during wet season
Rice ripens during dry
months of January and
February
Ripe rice is harvested and
dried before use
Commercial Rice Cultivation
Recent changes in cultivation have increased yield
and rice cultivation is now and example of
Intensive Peasant Commercial Agriculture.
Using the information on Page 249 + 250 of Core
Higher
1. Summarise these changes in a spider diagram
or as bullet points
2. Summarise the effects of these changes on
(i) the farming in Kedah and
(ii) the lives of the rice farmers
The Green Revolution
• Began in 1960 as a result of
• Research carried out at the International Rice Research
Institute (I.R.R.I.) in the Philippines.
• Involved the development and use of short-stem (do not
get damaged or flattened), high yielding cereals (rice,
maize, wheat) with short growing seasons which enables
two crops to be grown per year.
• Early success with IR8 rice, which has since been further
improved.
• Increased and improved mechanisation
• Increased and improved irrigation and drainage
• Increased use of agro-chemicals
= Increased yields
The Green Revolution
• Core Higher Page 254 Figure 8.38
What were the main (i) aims and (ii) results of the
recent rice breeding program at the I.R.R.I
2 In a table, summarise the main advantages
(successes) and disadvantages (failures) of the
Green Revolution, in terms of productivity,
equability and sustainability.
The Green Revolution
The future Green Revolution must be
(i) Sustainable
(ii) Accessible to all needy people in the
Developing World, and
(iii) Environmentally friendly
Sustainability can be achieved by a variety
of agricultural technologies
Using Figure 8.39 on Page 255 detail some
of these technologies
GRAIN FARMING ON NORTH
AMERICAN PRAIRIES
• Example of Extensive Commercial Farming
• Extends from northern Mexico through midwestern USA
and into Canada (Manitoba, Saskatchewan and Alberta)
• As you move northwards the growing season gets
shorter (300 in the south to less than 100 days in
Canadian Prairies)
• Rainfall decreases westwards
• Farm size increases westwards, because the climate
becomes more difficult so more land has to be farmed in
order to maintain yields.
• Crops from south to north are : cotton; winter wheat;
maize; spring wheat in the north
Grain Farming on North American
Prairies
• Very geometric settlement/ landscape
pattern
• Major immigration 120yrs ago and settlers
were given a 64 hectare plot. At this time
agriculture was intensive, however now
farms have been amalgamated into larger
units and Plains agriculture is now
extensive.
Grain Farming on North American
Prairies
• Marginal climate for farming because of
short growing season and low variable
annual rainfall.
• Droughts are common
• Very cold winters, temps of -15 to -20ºC
not uncommon.
• Irrigation is necessary
• By early 20th Century many farms had
failed
Grain Farming on North American
Prairies
Early 20th Century
• Farm sizes had increased – extensive
agriculture
• Improved agricultural technologies
• Steel plough, disc harrow, reaper, binder
• Pumps and windmills made irrigation easier as
water was pumped from aquifers (underground
water reserves within permeable rocks)
• New strains of fast growing spring wheat were
imported from Steppes of Russia (Russian
wheat growing plains)