Timescales for adaptations & transformations in African staple crops

Sonja Vermeulen, Head of Research, CCAFS

ccafs.cgiar.org

Recent NCC paper

Purpose of the research

• Assess likely effect of two different climate change scenarios on cultivation areas for nine most important crops in sub-Saharan Africa (50% food production, 40% value & 60% protein).

• Work out timeframes for adaptation policy and practice in order to maintain food security & livelihoods (first time this has been done).

• KEY MESSAGE: Possible to be prepared & pro-active ahead of the adaptation challenge.

Levels of impact & adaptation

When do we cross viability thresholds in African cropping systems?

Vermeulen et al PNAS 2012

Buzzword “transformation”

• AR5 WG2 2014: transformation involves “changes the fundamental attributes of a system in response to climate and its effects”

• Park et al. 2012 fundamental changes to function, form or location of the agri-food system

• Here we look at a very specific but important transformation case: shift away from cultivating a major staple crop in a given farming region

Methods

2 CMIP5 scenarios

19 GCMs

EcoCrop

suitability thresholds

Caveats:

Uncertainties in both models & drivers e.g. socio-economic change

Chance of more positive mitigation scenarios than 6.0 and 8.5?

Adaptations, including breeding, are not modeled – source of optimism

Crop suitability simulations were carried out for the historical period

(1961-1990) and for 93 years in 21st century (2006-2098)

Preparatory phase: suitability > viability threshold for 10-15 years in 20

Transformation phase: suitability > viability threshold for <10 years in a 20

Assumes farmers are “smart” and switch at 50% crop failure rate

Results: headlines

• Governments will need to prepare for possible large losses in national production potentials, and production

areas, of up to 15% by 2050 and over 30% by 2100.

• In some areas transformations will need to take place

as soon as 2025 which means the preparatory phase

must start now.

Results: which crops, when, where?

Which? Maize, bananas and beans

millets, sorghum, yams, cassava & groundnut are (mainly) stable.

When and where? Bananas

Northern Ghana

Togo and Benin,

which are highly

dependent on

bananas &

plantains for

nutrition, will need

to undergo

transformation in

the next ten years.

When and where? Beans

Beans will lose 60%

cropping area (RCP

8.5): 1.85 million

hectares of current

bean cropping

systems in Uganda

and Tanzania,

which grow 41% of

total sub-Saharan

African bean

supply, will be

unable to do so by

2100.

When and where? Maize Projected maize

transformations

represent 5% of

Nigeria's current

production by the

2050s and 25%

by 2100 (RCP 8.5)

0.5% maize areas

have no viable crop

substitution option

These areas total

0.8 Mha in the dry

zones of South

Africa (currently

grow 2.7 Mt)

Pockets of change for other crops too

e.g. Yam: early impacts,

but less coincidence

with areas of major

dependence

How should we respond?

Incremental phase

• Delay the threshold if possible (G x E x M)

• Genetic gains (15 year cycle)

• Management gains e.g. irrigation

Preparatory phase (15

years ahead)

• Prepare for transformations / substitutions

• Support to farmer & pvt sector innovation

• Flexible enabling environment

Transformation phase

• Crop substitution

• Farming system substitution

• Livelihood substitution

• Dietary substitution

How should we respond 1: delaying the viability threshold

Incremental phase

• Delay the threshold if possible

• Genetic gains (15 year cycle)

• Management gains e.g. irrigation (G x E x M)

Preparatory phase (15

years ahead)

• Prepare for transformations / substitutions

• Support to farmer & pvt sector innovation

• Flexible enabling environment

Transformation phase

• Crop substitution

• Farming system substitution

• Livelihood substitution

• Dietary substitution

Timeframe to release a new variety

Year activity

0 installation of a collection

1 selection of parents and multiplication

of selected parents

2-3 crosses and seed germination

4-5 F1 selection, cloning and evaluation

6-7 multiplication and crosses

8-9 F2 selection, cloning and evaluation

10-13 multi-locational testing

14-16 on-farm testing

17 large scale distribution

Understanding physiology of climate change impacts (heat- and drought-)

(Taiz and Zeiger, 2002)

• Transpiration ~ evaporative cooling

• Reduced transpiration: detect by Infrared imaging

Cachaco (ABB) Nakitengwa (AAAh)

Drought

Slide courtesy Rony Swennen, University of Leuven

Impacts on heat-sensitive common bean

But anything is possible with a great genepool

(a) Historical (b) Future (no adaptation) (c) Future (+3 ºC adapted)

Ramirez-Villegas and Thornton (2015)

Testing new varieties with farmers

Beans are a women’s crop

Important to combine heat-tolerance

and drought-tolerance with other

valued traits

Not looking to promote a single variety

everywhere; local preferences and

plasticity matter

Bean variety testing with 215 female &

143 male farmers

Men value traits: yield & market value

Women also value traits: short cooking

times, tastiness, high nutritional value

& climate responses

Mukankusi et al 2015. CCAFS WP 143

Drought-tolerant maize

Masuka et al. submitted

Yiel

d u

nd

er d

rou

ght

stre

ss (

t h

a-1

)

Current yield gain

Expected yield gains based on incorporating new technologies (doubled haploid, breeder ready markers, increased selection intensity, remote sensing, decision support tools)

Drought Tolerant Maize for Africa initiative has already benefited 30-40 million

people in 13 African countries.

Is more benefit possible?

Heat-tolerant maize

New heat stress tolerant hybrid Most popular hybrid in southern Africa

HEAD START: heat tolerance breeding work started

5 years ahead of demand from private sector –

ready in 2016 not 2021

How should we respond 2: preparation & transformation

Incremental phase

• Delay the threshold if possible (G x E x M)

• Genetic gains (15 year cycle)

• Management gains e.g. irrigation

Preparatory phase (15

years ahead)

• Prepare for transformations / substitutions

• Support to farmer & pvt sector innovation

• Flexible enabling environment

Transformation phase

• Crop substitution

• Farming system substitution

• Livelihood substitution

• Dietary substitution

Crop substitutions

Policy pointer: Invest now in

genetic gains in key substitution

crops

Farming system & livelihood substitutions

Jones & Thornton Env Sci Pol 2009

Up to 3% Africa’s land area

Support up to 35 million

people

Support up to 23 million

Tropical Livestock Units of

cattle, sheep & goats

Typically 8 hours travel to

centre of 250k people

Higher levels of poverty &

chronic under-nutrition

Likely shift from mixed

cropping to livestock

systems by 2050

Policy pointer: Target support for transformation to poorest regions

Dietary substitutions

Policy pointer: Take note of climate

change crop impacts in efforts to

promote dietary diversity & nutrition

Khoury et al PNAS 2014

1920s

Flexible enabling environments

- cross-border

biodiversity &

seed protocols

- national R&D

investments

- improved

input markets

- climate

information

and financial

services

- market

information &

extension

- finance for

processing

and storage

facilities

- piloting of

markets for

by-products

- consumer

education

- food and

nutrition

standards

- government

procurement

Improve conditions for self-directed change among

farmers, consumers and value chain participants

Conclusions / Recap

KEY MESSAGE: It is possible to be prepared & pro-active ahead of the adaptation challenge

SUPPORT:

1. Efforts to delay the crossing of viability thresholds

2. Flexible enabling environments for preparatory phases and transformations

Thank you for your

support to this research

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