Malthus is still Wrong - we can feed a world of 9 billion

Malthus is Still Wrong

We Can Feed a World of 9 Billion

Prabhu Pingali
Deputy Director
Agriculture Development

Plenary Presentation to the 7th International Conference of the Asian
Society of Agricultural Economists, held in Hanoi, Vietnam
October 13th, 2011

Views expressed are personal

The spectre of a Malthusian crisis
 The UN’s medium growth scenario has population increasing by 50%
between 2000 and 2050, from 6 billion to about 9 billion people.

 When coupled with significant nutritional improvements for the 2.1 billion
people currently living on less than $2/day (World Bank 2008), this
translates into a very substantial rise in the demand for agricultural
production.

 FAO estimates the increased demand at 70 percent of current
production, with a figure nearer 100% in the developing countries
(Bruinsma 2009).

 At the same time, the growing use of biomass for energy generation has
introduced an important new source of industrial demand in agricultural
markets (Energy Information Agency 2010).

October 23, 2011 © 2010 Bill & Melinda Gates Foundation |

Rising food prices have further
encouraged Neo-Malthusian
thinking


We’ve been there before


Recent Trends in Developing World Crop
Productivity Growth
 Production:
• Cereal output in developing countries has grown 2.8 percent annually for
three decades
 Productivity
• Yields, not area, were responsible for growth
• TFP grew along with yields
FAO food production index – total, per hectare, and per capita (1963=100)

Note: Numbers in parentheses are average annual growth rates for 1963–2000 - Estimates based on FAOStats and Hayami (2005)
Source: International Water Management Institute analysis done for the Comprehensive Assessment for Water Management in
Agriculture using the Watersim model, Chapter 2

Growth in food production outpaced growth in population
in all regions but Africa
FAO food production index – total, per hectare, and per capita (1963=100)

Note: Numbers in parentheses are average annual growth rates for 1963–2000 - Estimates based on FAOStats and Hayami (2005)
Source: International Water Management Institute analysis done for the Comprehensive Assessment for Water Management in
Agriculture using the Watersim model, Chapter 2

Evidence on factors contributing to productivity
growth
100%

90% Ag R&D & extension

80%
Inputs Delivery - Ag.
70%
credit/insurance
Inputs Delivery - Fertilizer,
60% pesticide, seed, machinery, etc
Infrastructure - Electricity,
50%
health/education, telecomm
40% Infrastructure - Irrigation

30% Infrastructure - Rural Roads
20%
Policies/institutions -
10% Macro/sectoral/legal reforms

0%

October 23, 2011 © 2010 Bill & Melinda Gates Foundation | 7

Looking Ahead: Getting the demand
side right


Percent change in monthly per capita cereal consumption
in rural and urban India: 1993/94 and 2004/05

Source: NSSO Reports: Household Consumption Expenditure in India

Diets in developing countries will continue to
diversify...

Source: FAO, World Agriculture to 2015/2030


... With rises in income leading to increased
demand for meat and a concomitant rise in feed
Meat consumption more than doubles in East Asia by 2050

Feed demand drives future demand for grains


Developing countries are spending a growing
share of GDP on food imports
Share of food imports in GDP in developing countries, 1970-2001

Processed and high value products are
increasing in share of food trade

Source: Regmi et. al., 2001, USDA

BioFuel demand – the focus is
shifting away from food grains to
other sources of biomass


Can rising food/feed demand be
accommodated without a significant
increase in the land area cultivated?


Land expansion vs. intensification
The Global Agro-Ecological Zone (GAEZ) study published in 2002 (Fischer et
al., 2002), combining soil, terrain and climate characteristics with crop
production requirements and various technological levels, estimated that:

• About 30% of the world’s land surface, or 4.2 billion ha is suitable to some
extent for rainfed agriculture.
• Of this area some 1.7 billion ha are already under cultivation.
• This would leave a gross global balance of 2.5 billion ha of land suitable
for cultivation.

But this favorable impression must be qualified by a number of considerations

• Other land uses (urban areas, protected areas, forests)
• Uneven geographical distribution
• Biotic, abiotic, socioeconomic and farm management constraints

There are significant opportunities for intensification of land already
under cultivation.


Significant opportunities to boost productivity

Cropland distribution and average annual yield

Source: West. P.C, et al., Nov 2010, “Trading Carbon for Food: Global comparison of carbon stocks vs. crop yields on
agricultural land”. PNAS, vol. 107, no. 46, 19647


Can the physical constraints to
productivity growth be overcome?


Land quality: SSA and SA are plagued by severely
degraded soils
In Bihar, India soil NPK depletion
occurs at 80 kg / ha / year3

Over the last 30 years,
African soils lost on
average 22 kg of N, 2.5 kg
of P, and 15 kg of K per ha
of cultivated land – an
annual loss equivalent to
U.S. $4B in fertilizer.1

83% of land in SSA is
problematic for In Bangladesh, declines in soil
agriculture: 55% is fertility lead to annual losses of
classified as ~4M tons of cereal production,
unsustainable for crop valued at US ~$566M4
production, and 28% is
classified as medium or Very degraded soil Stable soil
low potential2 Degraded soil Without vegetation

Humans cause erosion at 10 to 15 times faster rates than natural processes.
Over the past 500M years, soil eroded at an average of one inch per 1,000 years.
Today, it takes just 40 years to erode one inch.5
Source: 1. Sanchez 2002; 2. AGRA Soil Health in Africa; 3. R. Lal 2009; 4. Hasan and Alam, 2006; 5. Wilkinson 2004. Map: UNEP

Soil health is a key enabler of sustained
productivity improvements
No matter how effectively other conditions are remedied,
per capita food production in Africa will continue to decrease unless soil
fertility depletion is effectively addressed. – Sanchez and Jama 2002

Soil health impacts baseline yields and enhances
the effectiveness of inputs

Poor Soil Health

Good Soil Health

Maize yield response to various nutrient combinations
Source: S. Zingore 2011

The Brazilian Cerrado case highlights how
sustained soil management can recover fertility
With the intensification of production,
Brazil has continued to achieve
increasing yields without significantly
increasing land under cultivation

No-till
farming on
Intervention

Lime over 50% of
Intercropping
application & land to leave
of nitrogen-
acid-tolerant more crop
fixing legumes
seed varieties residue in
fields
Constraint

High soil Low organic Low
acidity matter nitrogen

Source: The Economist; Dierolf 2000.

Water scarcity will be a growing constraint

 Sectoral competition is
increasing for blue water
withdrawals for human
uses

 Direct and indirect
negative effects have been
well documented, these
include:
• Declining water tables
• Drainage of wetlands;
• Nutrient loading of surface
water and groundwater;
• Salinization and waterlogging
of soils;
• Agrochemical contamination;
• Siltation of rivers.

Water use can be better managed
Water withdrawal and consumption by region


Managing Rainfed Agriculture

 Changing cropping patterns

 Improved tolerance to drought and submergence

 Increased use of hybrids

 Better land & water management practices


Climate change adaptation & mitigation
practices are compatible with sustainable
intensification

Demand is growing for carbon
 Conservation tillage systems credits but agriculture is only 3%
of market share
 Drought and water
management practices

 Incentives for moving
agriculture out of marginal
areas

 Market mechanisms for
carbon sequestration


What should we do: Policy Actions
 Keep the focus on agriculture and invest in smallholder
productivity growth

 Technology, including biotechnology, will be an important part
of the solution

 Policies (including trade policies) that enable and encourage
smallholder productivity growth are crucial

 Pay particular attention to stress prone environments

 Invest in a long term strategy for biofuels that does not rely on
increased use of food grains


Malthus will be proven
wrong once again
because of our
ingenuity and our
ability to deal with
resource scarcity
through technical
innovation and
focused policy change


Malthus is still Wrong - we can feed a world of 9 billion

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