2013年-世界发展银行全球_Potential_Impact_of_Climate_Change_on_Resilience_and_Livelihoods_in_Mixed_Crop-Livestock_Systems_in_East_Africa_133页_1mb

Summary of the Study: Potential Impact of Climate Change on Resilience and Livelihoods in Mixed Crop-Livestock Systems in East Africa

Core Content

This report presents a World Bank study conducted by the International Livestock Research Institute (ILRI) on the potential impact of climate change on mixed crop-livestock systems in East Africa. The study focuses on how climate change might lead to shifts in livelihood strategies, particularly from crop-based to livestock-based systems, and explores the implications of such transitions for resilience, food security, and poverty reduction.

Main Objectives

The primary objectives of the study were:

• To identify areas in mixed crop-livestock systems where climate change could compel sedentary farmers to abandon cropping and adopt nomadic pastoralism.
• To assess the social, economic, and environmental impacts of such a transition.
• To determine the biophysical thresholds or tipping points that would trigger a shift from crop agriculture to pastoral nomadism.

Key Findings

Historical Changes

• Cropping has been introduced in most of the 12 study sites in the last 50 years.
• Maize is the dominant crop, but some households are diversifying into drought-tolerant crops.
• Food insecurity is common in areas with less than 800 mm of annual rainfall, and critical levels are seen in areas with less than 700 mm.
• In seven of the 12 sites, households are self-sufficient in dietary energy, while others rely on food aid.

Current Livelihoods and Adaptation Strategies

• Households across all sites are concerned about water scarcity, both for human consumption and livestock.
• Coping strategies include searching for water, drilling boreholes, buying food, and reducing consumption.
• Adaptation strategies vary with rainfall levels:
  • In low rainfall areas: income diversification, expansion of cropping, and increasing herd sizes.
  • In higher rainfall areas: food storage, planting drought-resistant cultivars, and intercropping.
• Livestock mobility is a key strategy in response to pasture shortages.

Future Projections

• Climate models suggest that some areas may become drier, increasing the risk of crop failure and reducing the viability of crop production.
• Drought-tolerant crops such as millet, sorghum, cassava, and cowpeas are likely to play a more significant role in future farming systems.
• Some households may benefit from increased cropping opportunities in certain areas, but others are expected to face worsening food insecurity and poverty.
• The study found that increasing livestock numbers could reduce household vulnerability, especially in drier areas.

Methodology

The study used a mixed-methods approach, combining:

• Quantitative and qualitative analysis to assess changes in farming systems.
• High-resolution climate data and weather modeling using MarkSim to simulate daily climate conditions.
• Cluster analysis to select 12 representative sites across Kenya, Tanzania, and Uganda.
• Household-level modeling to evaluate the impacts of climate change on income and food security.
• Key-informant interviews and surveys to gather on-the-ground data on current farming practices and challenges.

Policy and Institutional Implications

• Drought-tolerant crops need to be promoted through improved seed distribution and knowledge transfer.
• Policy measures should encourage diversification of diets and support the adoption of new crops like sorghum, millet, and legumes.
• Safety nets and market development are essential for supporting vulnerable households in drier areas.
• Weather forecasting and crop and livestock insurance could help reduce the risks associated with climate change.
• Adaptation investments are critical to create an environment conducive to technological change and adoption.

Key Challenges and Opportunities

• Uncertainty remains in climate models regarding future rainfall patterns, which affects the reliability of projections.
• Adaptation strategies must be tailored to local conditions and include both crop and livestock diversification.
• Economic opportunities and market access are key to enabling sustainable transitions in farming systems.
• Social and cultural factors play a significant role in shaping livelihood strategies and dietary preferences.

Conclusion

The study highlights the potential for climate-induced changes in mixed crop-livestock systems in East Africa, with implications for food security, poverty, and livelihood strategies. While no direct evidence of a shift to nomadic pastoralism was found, the study indicates that such transitions are likely in certain areas under projected climate scenarios. The findings suggest the need for targeted policies and institutional support to help farmers adapt to these changes and maintain resilience in the face of climate variability and uncertainty.