2017年-世界发展银行全球_Agricultural_Intensification___The_Status_in_Six_African_Countries_15页_2mb

Summary of "Agricultural Intensification: The Status in Six African Countries"

Core Content

This paper examines the status of agricultural intensification in six African countries—Ethiopia, Malawi, Niger, Nigeria, Uganda, and Tanzania—using national representative household data from the Integrated Surveys on Agriculture (ISA). The study builds on the Boserup-Ruthenberg (BR) framework, which posits that population growth and market access are the main drivers of agricultural intensification, leading to increased productivity, input use, and shifts in land use.

The BR framework predicts that intensification will result in reduced fallow periods, higher use of fertilizers and organic manure, increased mechanization, and improved infrastructure and market access. However, the paper argues that these predictions are only partially supported in the African context, due to limited technological adoption, insufficient investments in irrigation, and the lack of sufficient evidence for the expected productivity gains.

Main Viewpoints

• Population Growth and Market Access: These are the primary forces driving agricultural intensification. They increase pressure on land and create incentives for more efficient production.
• Agricultural Intensification Trends: In many areas, fallow areas have disappeared, and cropping intensity has increased, but soil fertility remains low, and fertilizer and irrigation use are inadequate.
• Agricultural Involution: A concept introduced by Geertz, it refers to the situation where intensification leads to increased labor input without corresponding increases in productivity or income, often resulting in declining economic and social well-being.
• BR Framework Limitations: The framework has not been fully realized in Africa due to slow technological change, limited investment in infrastructure, and insufficient data for rigorous testing.
• Need for Panel Data: The paper emphasizes that panel data are necessary to rigorously test the BR framework and its predictions about the relationship between intensification variables and their drivers.

Key Information

Variables and Measures

• Agro-ecological Potential (AEP): A measure based on global crop yield models from the GAEZ data portal. It reflects the potential productivity of a given area, taking into account soil, terrain, and climate conditions.
• Urban Gravity (UG): A proxy for urban demand and economic opportunities, calculated using night light intensity data and the distance from urban centers. It is used to estimate the impact of urban centers on agricultural intensification.
• Intensification Variables: Include population density, cropping intensity, fallow periods, irrigation use, and the adoption of various technologies (organic manure, chemical fertilizers, pesticides, etc.).

Findings

• Descriptive Analysis: Shows that while some intensification patterns align with BR predictions (e.g., reduced fallow, increased cropping intensity), others (e.g., fertilizer and irrigation use) do not.
• Causal Relationships: The paper estimates the causal impact of AEP and UG on intensification variables, using a regression model. However, due to the lack of panel data, these estimates cannot fully test the BR framework.
• Policy and Institutional Factors: The BR framework assumes that governments and communities will invest in infrastructure and markets in response to agro-ecological potential and urban demand. This is not always the case in Africa.
• Comparison with BR Predictions: The results suggest that agricultural intensification in Africa has not fully achieved the expected productivity and income gains, indicating the possibility of involution.

Research Contributions

• New Measures: The paper introduces internationally comparable measures of AEP and UG, which can be used to analyze the impact of these factors on agricultural intensification.
• Cross-Country Analysis: It uses cross-sectional data from the first year of the ISA studies to describe the current state of agricultural intensification in the six countries.
• Future Research Directions: The paper highlights the need for panel data to rigorously test the BR framework and to assess the long-term effects of intensification on productivity and welfare.

Conclusion

While the BR framework provides a useful theoretical basis for understanding agricultural intensification, its application in Africa is limited by slow technological progress, inadequate investment in infrastructure, and insufficient data. The study finds that agricultural intensification has occurred in some forms, but not in all, and that the process may be leading to involution in certain areas. The paper contributes to the ongoing debate on agricultural intensification in Africa and underscores the importance of continued research and policy support to achieve sustainable intensification.