2008年-世界发展银行全球_Can_China_Continue_Feeding_Itself__The_Impact_of_Climate_Change_on_Agriculture_41页_1mb

Can China Continue Feeding Itself?

Core Content

This working paper investigates the impact of climate change on China's agricultural production and assesses whether China can continue to feed its population despite global warming. The study uses a Ricardian analysis approach, which evaluates the relationship between climate variables and net crop revenues at the farm level, based on survey data from 8,405 households across 28 provinces in China.

Main Points

• China's Food Security: China has historically been able to meet its food needs, but this study explores whether climate change will alter this trend.
• Climate Change and Agriculture: The paper highlights that climate change, particularly rising temperatures and changing precipitation patterns, will have varying impacts on different regions of China.
• Regional Impacts:
  • Mid-latitude regions may benefit from warming.
  • Southern and northern regions are likely to be harmed.
• Precipitation Effects: More precipitation is generally beneficial to Chinese farmers, except in the wet southeast.
• Irrigation and Rainfed Farms:
  • Irrigated and rainfed farmers have similar responses to precipitation.
  • Irrigated farms may benefit from warmer temperatures, while rainfed farms are likely to be harmed.
• Seasonal Variations: Seasonal effects are significant and may offset each other. For example, higher spring temperatures are harmful, while warmer summer and winter temperatures are beneficial.
• Limitations of the Study:
  • The study does not account for the indirect effects of climate change on agriculture through changes in water availability.
  • It does not include price changes or transition costs, which may affect the welfare of farmers.
• Methodology: The paper uses the Ricardian method, which assumes farmers maximize net income based on exogenous conditions such as climate, land, and irrigation. The model is specified as a quadratic function to capture the nonlinear relationship between climate and net crop revenue.

Key Findings

• The average net crop revenue in China in 2001 was 10,146 Yuan per hectare (1353 USD).
• Irrigated villages had higher net revenues (12,319 Yuan per hectare or 1643 USD) compared to rainfed villages (7,464 Yuan per hectare or 995 USD).
• The Ricardian regression analysis shows that climate variables significantly affect net crop revenues, with non-linear impacts.
• The temperature elasticity is approximately -.09, meaning that a 1% increase in temperature leads to a 0.09% decrease in net revenue.
• The goodness of fit for the models is relatively high, ranging from 0.17 to 0.26.

Policy Relevance

• The study emphasizes the importance of considering climate change in agricultural policy planning.
• It suggests that while some farmers may benefit from warming, others will face significant losses, potentially offsetting gains.
• If future climate scenarios lead to reduced water availability, the impacts on Chinese agriculture could be severe and not fully captured in this study.
• The findings highlight the need for adaptation strategies and further research to understand the indirect effects of climate change on water availability and agricultural productivity.

Future Research Suggestions

• Include data on water availability and cost to better understand the indirect effects of climate change on irrigation.
• Account for price changes and transition costs in future studies to improve the accuracy of welfare assessments.
• Explore seasonal variations in more detail to refine the understanding of how climate change affects different crops and regions.

Conclusion

The study concludes that while climate change may have mixed effects on China's agriculture, the overall impact is uncertain. The potential for both gains and losses suggests that adaptation strategies are essential to ensure China's continued ability to feed itself. Further research is needed to fully capture the complexities of climate change on agricultural productivity, particularly the role of water availability and economic factors.