the larger context of rice terraces glenn davis stone washington univ., st. louis the ifugao rice...
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The Larger Context of Rice Terraces
Glenn Davis StoneWashington Univ., St. Louis
The Ifugao Rice Terraces: Antiquity, Management, and Conservancy
June 18, 2015
National Museum, Manila
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Boserup, Ester (1965) The conditions of agricultural growth: The economics of agrarian change under population pressure.
Theory of agricultural intensification• "dynamic model for all primitive agriculture" • Boserup -- input of mostly local resources• industrialization -- use of off-farm resources, mostly produced industrially
Extensive Intensive
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• Extensive (shifting, slash & burn, swidden) capitalizes on fire & fallow• Fire clears canopy, fertilizes, kills pests• Fallow re-fertilizes, removes pest habitat, creates fodder• Broadcast or dibble seeds, little fertilizing, weeding• Used when possible because efficient (low input:output)
• Population pressure reduces fallow area• Fertilizing• Tillage• Weeding• Bring more labor-intensive land into cultivation
(“locational intensification” Stone 1996)
•Overall effects:
• Longer work hours• Output per area/time rises • Efficiency drops; decreasing marginal returns
Ecology of Intensification Extensive Intensive
PO
PU
LATIO
N
AGRICULTURAL INTENSITY
Tree fallowvery high efficiency
Bush fallowhigh efficiency
Boserupian Intensification
PO
PU
LATIO
N
AGRICULTURAL INTENSITY
Tree fallowvery high efficiency
Bush fallowhigh efficiency
Grass fallowmedium efficiency
Boserupian Intensification
PO
PU
LATIO
N
AGRICULTURAL INTENSITY
Tree fallowvery high efficiency
Bush fallowhigh efficiency
Grass fallowmedium efficiency
Annual cultivationlow efficiency
Boserupian Intensification
PO
PU
LATIO
N
AGRICULTURAL INTENSITY
Tree fallowvery high efficiency
Bush fallowhigh efficiency
Grass fallowmedium efficiency
Annual cultivationlow efficiency
Multi-croppingvery low efficiency
Boserupian Intensification
PO
PU
LATIO
N
AGRICULTURAL INTENSITY
Tree fallowvery high efficiency
Bush fallowhigh efficiency
Grass fallowmedium efficiency
Annual cultivationlow efficiency
Multi-croppingvery low efficiency
Boserupian Intensification
T E R R A C I N G
• Boserup’s theory ties agricultural intensity to population pressure, as opposed to "grand, inclusive schema like those of cultural evolution" • (Stone & Downum 1998, “Non-Boserupian Ecology”; Netting Smallholders 1993:261)
• It can reverse: when population density drops, intensity drops (e.g., Kofyar)
• Driving force in agricultural practices is efficiency (returns to labor)
• Simplified but invaluable model of agricultural change
Is wet rice RICE Boserupian?
In some ways:
high input high outputoften under high population density
as she predicts
But relatively efficient!
"Where a transition from broadcast sowing to transplanting, or from single- to double-cropping is made, the increases in yield will certainly outstrip concomitant rises in labour inputs.“
Francesca Bray 1986:5, The Rice Economies
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“Soup bowl ecology”
• Nitrogen fixing bacteria
• Water extremely effective weed control
• Years of continuous cultivation develops good waterproof hardpan covered in mud (podzolisation)
• May hold fertility indefinitely (at least at a certain level of multicropping)
• Ponds conducive to other economic species
Philippines China Louisianaextensive wet industrial
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labor hrs/ha 576 3045 25animal hrs/ha 272 332 0energy kcal/ha 1.8 mil 7.6 mil 11.5 milyield kcal/ha 6 mil 29 mil 15 milyield kg/ha 1700 8000 4100efficiency 3.3 3.2 1.3(kcal output:input)
(Source: Wen & Pimental 1986)
Input/Output (efficiency) comparisons
Extensification normally easy• Kofyar switched to slash & burn
But especially on steep hills, terracing may have a “ratchet” effect• Incentives to maintain whole system
Rice Terraces
Rice is agro-ecologically unique• Contrary to theories of agricultural change,
this intensive form of cultivation if relatively efficient
Terraces are a unique form of intensification• Can exert ratchet effect• Form of architecture• Landscape feature with value beyond
agriculture