malthus is still wrong - we can feed a world of 9 billion

Malthus is Still Wrong

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

We Can Feed a World of 9 Billion

The spectre of a Malthusian crisis

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

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).

Rising food prices have further encouraged Neo-Malthusian

thinking


http://www.fao.org/worldfoodsituation/wfs-home/foodpricesindex/en/

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

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

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)

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

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Ag R&D & extension

Inputs Delivery - Ag.credit/insurance

Inputs Delivery - Fertilizer,pesticide, seed, machinery, etc

Infrastructure - Electricity,health/education, telecomm

Infrastructure - Irrigation

Infrastructure - Rural Roads

Policies/institutions -Macro/sectoral/legal reforms

Evidence on factors contributing to productivity growth

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


Meat consumption more than doubles in East Asia by 2050

Feed demand drives future demand for grains

... With rises in income leading to increased demand for meat and a concomitant rise in feed


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.


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

Cropland distribution and average annual yield


Significant opportunities to boost productivity

Can the physical constraints to productivity growth be overcome?


Source: 1. Sanchez 2002; 2. AGRA Soil Health in Africa; 3. R. Lal 2009; 4. Hasan and Alam, 2006; 5. Wilkinson 2004. Map: UNEP

Very degraded soil Stable soil

Degraded soil Without vegetation

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

agriculture: 55% is

classified as

unsustainable for crop

production, and 28% is

classified as medium or

low potential2

In Bihar, India soil NPK depletion

occurs at 80 kg / ha / year3

In Bangladesh, declines in soil

fertility lead to annual losses of

~4M tons of cereal production,

valued at US ~$566M4

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


Land quality: SSA and SA are plagued by severely degraded soils

Maize yield response to various nutrient combinations

Soil health is a key enabler of sustained productivity improvements

Source: S. Zingore 2011

Poor Soil Health

Good Soil Health

Soil health impacts baseline yields and enhances the effectiveness of inputs

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


Intercropping

of nitrogen-

fixing legumes

Lime

application &

acid-tolerant

seed varieties

No-till

farming on

over 50% of

land to leave

more crop

residue in

fields

The Brazilian Cerrado case highlights how sustained soil management can recover fertility

High soil

acidity

Low organic

matter

Low

nitrogen

Source: The Economist; Dierolf 2000.

Co

ns

tra

int

Inte

rve

nti

on

With the intensification of production, Brazil has continued to achieve increasing yields without significantly increasing land under cultivation


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 withdrawal and consumption by region


Water use can be better managed

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

Conservation tillage systems

Drought and water

management practices

Incentives for moving

agriculture out of marginal

areas

Market mechanisms for

carbon sequestration

Demand is growing for carbon credits but agriculture is only 3% of market share


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

Documents

bill melinda gates foundation

land area

share of food trade

growth tfp

rising food prices

land expansion

increased demand

foodfeed demand