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Takefumi Fujimoto (presenter)

Aya Suzuki

Department of International Studies

Graduate School of Frontier Sciences

The University of Tokyo

Different Strategies of Crop Diversification

Between Poor and Non-Poor Farmers

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-Concepts and Evidence from Tanzania-

(Two agricultural plots )

Research topic: crop diversification (CD) in Tanzania

→ Farmers grow diverse variety of crops, rather than one crop

Ex) maize, rice, sorghum, beans, tomato, carrot, cotton …

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MAIZE ONLY

Farmers grow only maize

→ No crop diversification

MAIZE

BEANS

TOMATO

Sorghum

Farmers grow diverse crops

→ Crop diversification

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Two benefits of CD:

(1) To reduce agricultural risks

・Wide range of planted crops provides wide adaptability to agronomic shocks (e.g., drought, crop diseases)

・Diverse composition of harvested crops provides robustness to price fluctuation in markets

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(2) To increase income among poor farmers

・Productivity increases by agronomic synergies between crops (e.g., intercropping legumes)

→ CD has been empirically found to benefit the poorest the most (Michler & Josephson 2017; Asfaw et al. 2018; Asfaw et al. 2019; Tesfaye & Tirivayi 2020)

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(Purpose)

To clarify poor and non-poor farmers adopt different strategies of CD

・Poor farmers pursue CD for robust food securities

・Non-poor farmers adopt CD to stabilize market income

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This presentation:

(1) Explains why poor & non-poor farmers have different motivations for CD

(2) Empirically shows poor & non-poor farmers adopt CD differently:

・poor farmers respond to shocks on food securities

・Non-poor farmers respond to shocks on market income

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Contents

• Conceptual Framework
• Dataset & Methodology
• Results

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Conceptual Framework

→ farmers’ utility maximization framework

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We must consider two issues:

(1) How to express difference between poor & non-poor farmers

→ Poor farmers with low income prioritize consuming particular goods for survival

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(2) How to express risk-reducing nature of CD

→ Crop diversity in farmland alleviates uncertainty

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Budget line

Indifference curve

→ Solution in customary consumer problem

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Subsistence line

Must be consumed

above subsistence line

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Conceptual Framework

Hypothesis:

Poor/non-poor farmers adopt CD in a different manner

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Three potential factors behind different motivations for CD:

・Subsistence requirement (poverty traps v.s. risk dispersion)

・Balanced dietary intakes

・Stabilization of market income

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Subsistence requirement

Priority of poor farmers:

→ To satisfy the subsistence constraint in any state

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Poor farmers may or may not adopt CD

1. Poverty traps (CD↓)

Poor farmers specialize in producing high-calorie crops for survival

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(2) Risk dispersion (CD↑)

Poor farmers adopt CD to disperse risks

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Poverty traps (CD↓)

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Poverty traps (CD↓)

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Poverty traps (CD↓)

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Risk dispersion (CD↑)

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Risk dispersion (CD↑)

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Subsistence requirement

Poor farmers may or may not adopt CD for survival

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(1) Poverty traps

High crop diversity involves risks of insufficient energy intakes

⇒ CD↓

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(2) Risk dispersion

Specialization in a certain crop involves risks of heavy damages

⇒ CD↑

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Balanced dietary intakes

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Balanced dietary intakes

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Balanced dietary intakes

Moreover, income increase frees consumption restriction by the subsistence constraint

→ Poor farmers can choose consumption as they prefer

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Stabilization of market income

The subsistence constraint is NOT binding among non-poor farmers

→ Non-poor farmers can consume luxury food and non-food items

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⇒ Non-poor farmers try to stabilize market income used for their purchases by CD

Summary of Conceptual Framework

Three potential factors behind CD between poor/non-poor farmers

・＋ : CD increases

・－ : CD decreases

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Farmers experienced shocks in the past

→ They recognize possible risks in relation to three factors

→ They determine crop diversity to address future risks

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Contents

• Conceptual Framework
• Dataset & Methodology
• Results

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Dataset

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Tanzania National Panel Survey (LSMS-ISA)

・Nationwide questionnaire for households

・Collect socioeconomic & agronomic information

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Farmers in Tanzania’s mainland

→ Balanced panel of 1,332 farmers in each 2010 & 2012

Indicators of Crop Diversification

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Indicators of Crop Diversification

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Methodology

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Methodology

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Contents

• Conceptual Framework
• Dataset & Methodology
• Results

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Results (Simple Count of Crop Number)

Poor farmers increase crop number against past drought/flood

→ Poor farmers may build farming systems robust to heavy damages

⇒ Subsistence requirement (risk dispersion)

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(Standard errors in parentheses)

Results (Simple Count of Crop Number)

Poor farmers increase crop numbers against rise in food price

・Food price↑⇒consumption↓

→ Poor farmers address a threat to food security

⇒ Subsistence requirement (risk dispersion)

& Balanced dietary intakes

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(Standard errors in parentheses)

Results (Simple Count of Crop Number)

Non-poor farmers increase crop number against past fall in crop price & rise in input price

・Crop price↓ ⇒ Income ↓

・Input price↑ ⇒ Cost ↑

→ Non-poor farmers address threats to market income

⇒ Stabilization of market income

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(Standard errors in parentheses)

Results (Simpson Index)

Poor farmers increase SI against drought/flood &

rise in food price

→ Consistent with results of crop numbers

・build robust farming systems

・address a threat to food security

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(Standard errors in parentheses)

Results (Simpson Index)

Poor farmers decrease SI against livestock loss

・livestock is labor for tillage & seed planting

→ Poor farmers cannot repurchase livestock

→ low ability of cultivation

→ CD is discouraged (Subsistence requirement: poverty trap)

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(Standard errors in parentheses)

Summary of results

Poor and non-poor farmers have different motivations for CD

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Poor farmers:

・Poor farmers adopt CD for food security

・Poor farmers may be trapped in poverty due to loss of productive assets

Non-poor farmers:

・Non-poor farmers adopt CD to stabilize income obtained from market transactions

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