Soil Carbon Sequestration:

The Triple Win Strategy for Food

Security, Climate Resilience and Low

Emission Agriculture

Ademola Braimoh, PhD

Introduction

• The link between agriculture and human well-being

will grow stronger in the 21st Century because of

the enormous promise that agriculture offers for

growth, poverty reduction and supply of ecosystem

services

• Seventy-five percent of the world’s poor live in rural

areas and depend on agriculture for their

livelihood.

• By 2050, agricultural production will need to

increase by 70% to feed the world’s 9 billion

people

• Accelerating climate change is an additional challenge

to meeting the food security needs of the increasing

population.

• Global surface temperature has risen by 0.8oC since the

late 19th Century.

• Average rate of increase is 0.15oC per decade since

1975 (IPCC, 2007).

• Projected increase during the 21st Century is 1.5 –

5.8oC (IPCC, 2001).

• Intensification of hydrologic scarcity and variability.

• Crops have to grow in hotter and drier conditions.

• Higher temperatures and shorter growing seasons will

reduce the yields of most crops

• Changes in precipitation pattern will increase the

likelihood of short-run crop failures and long-run

productivity declines (IFPRI, 2009).

• Overall impact is expected to threaten food security.

Impacts of Climate Change on Food Production

• Effects of land-use change on soil carbon is a major concern in

international policy agenda

• Agriculture and forestry sector account for about one-third of global

emissions.

• Most agricultural soils have lost 30 – 40 t ha-1 (30% - 75%) of their

antecedent soil organic C pool (Lal et al. 2007)

• Degree of loss is higher in soils that are susceptible to accelerated

erosion.

• If a given land-use change (deforestation) leads to soil carbon

losses, then the reverse change (reforestation) could potentially

increase carbon stock

Land use as a source of emissions

• However, it can take several years to recover the original level

of soil carbon stock after such a significant disturbance to the

land system.

So

il C

Time

Steady state A

Steady state D

Steady state C

Steady state B

Steady state E

Disturbance

New management

Influence of management on SOC

• Improved land management practices has large mitigation

potentials

• 5.5 – 6.0 Gt CO2 equivalent by 2030; 89% through carbon

sequestration.

Land use as a sink of emissions

0 1000 2000 3000 4000 5000 6000 7000

Up to $20

Up to $50

Up to $100

Biophysical potential

Mt CO2 - equivalent

A2; a more divided world, a world of independently operating, self-reliant nations

B2; a world more divided, but more ecologically friendly

A1b; a more integrated world with a balanced emphasis on all energy sources

B1; a world more integrated, and more ecologically friendly

Mitigation potential across world regions (Mt CO2-eq)

70% of the potential resides in developing countries

Soil Carbon Sequestration Potential

Values in parentheses

are in kg C ha-1 yr -1 (Lal 2004)

Soil Carbon Sequestration potentials in Sub Saharan Africa

Land management practice Attainable rates Mg ha-1yr-1

Natural or improved fallows 0.1 – 5.3

Manure, crop residues and no till on

croplands

0 – 0.36

Permanent cropland with no till 200 -1500

Permanent croplands with fallow 400 – 18500

Fallow systems Up to 28500

Vagen et al (2005)

Soil Carbon Sequestration and Crop Yields

Expected change in cereal yields by increasing soil organic C

in the root zone by 1% in different countries (based on Lal,

2010)

Change in yield (Mg ha-1) Crop Country

2.24 Wheat Argentina

1.76 Maize Northeast China

1.01 Rice India

2.87 Maize Nigeria

0.33 Wheat Russia

Soil carbon sequestration provides ancillary benefits

including

• Reduced soil erosion

• Improved soil structure

• Increased nutrient holding capacity

• Increased nutrient use efficiency (spend less on

fertilizers)

• Reduction in land requirement for farming -

agricultural intensification - less emissions

Constraints to adoption of soil carbon

sequestration practices

• Land tenure/property rights

• Displacement of emissions

• Permanence

• Monitoring costs

• Absence of incentives -(e.g. non recognition by

CDM, lack of insurance/risk management, PES)

Moving the Soil Carbon Agenda Forward

Improved knowledge of

• Carbon sequestration potential of sustainable land

management practices across agroecological

zones

• The trade-offs and synergies between carbon

sequestration and food security that is associated

with changes in land management practices.

• The role of socioeconomic and institutional factors

in the adoption of sequestration practices

• The appropriate incentives for soil carbon

sequestration in different regions of the world.

Soil Carbon Assessment at the World Bank

We intend to develop an open source, geospatial database for

soil carbon monitoring for specific land uses

Examples of scenario questions answered by the database:

• What is the carbon sequestration rate of soils in

locations X, Y and Z?

• Given the soil and climate conditions of location A, what

cultivation and management practices are required to

achieve a carbon sequestration of x tons and when will

this be achieved?

• What is the effect on carbon storage if management

practice changes from P to Q and in what year will

carbon sequestration reach saturation?

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You can contribute ideas, data and other

information to the database development by

sending e-mail to abraimoh@worldbank.org