世界银行-自然的经济案例：评估发展政策路径的全球地球经济模型（英文）-2021.7-183页_6mb

Summary of "The Economic Case for Nature"

Core Content

This report, The Economic Case for Nature, presents a global integrated modeling exercise to assess the economic implications of biodiversity and ecosystem service loss, and to demonstrate the benefits of nature-smart policies. It emphasizes the critical role of nature in supporting economic development and highlights the risks of inaction, particularly for low-income and lower-middle-income countries. The study uses a computable general equilibrium (CGE) model to evaluate the impact of changes in key ecosystem services on global GDP and the broader economy, from 2021 to 2030.

Key Findings

• Biodiversity and Ecosystem Services as Development Issues:
  The decline in biodiversity and ecosystem services is a significant development challenge. Economies, especially in low-income countries, are heavily dependent on natural capital for growth and resilience. The loss of ecosystem services can lead to substantial economic losses, with a projected global GDP decline of $2.7 trillion by 2030, or 2.3% annually, if key services such as wild pollination, marine fisheries, and native forest timber provision collapse.

• Impact on Low-Income and Lower-Middle-Income Countries:
  These countries are most vulnerable to ecosystem service loss, with potential GDP declines of 9.7% in Sub-Saharan Africa and 6.5% in South Asia by 2030. The report highlights that these regions rely heavily on pollinated crops and forest products, and have limited options to adapt to the loss of these services.

• Nature-Smart Policies as Win-Win Solutions:
  Policies that are nature-smart can reduce the risk of ecosystem collapse and improve economic outcomes. The report outlines several policy pathways that demonstrate how integrating nature into economic decision-making can yield positive results. These include:

  • Decoupled support to farmers (P1): Reforming agricultural subsidies to remove incentives for converting natural land to cropland or pasture.
  • Domestic and global forest carbon payments (P2 and P3): Incentivizing landowners to conserve forest carbon sinks.
  • Investment in agricultural R&D (P6): Increasing public investment in research and development to improve productivity on existing agricultural land.

• Combined Policy Impact:
  The most effective outcomes are achieved when multiple nature-smart policies are implemented together. For example, combining decoupled support to farmers with a global forest carbon payment and agricultural R&D investment results in:

  • A 50% reduction in natural land conversion compared to business-as-usual.
  • A global GDP increase of up to $150 billion.
  • A reduction in natural land loss by 38% (18 million hectares) when combined with domestic subsidy reform.

• Climate Change Synergies:
  Nature and climate change are closely linked. Policies that address both can yield significant economic and environmental benefits. For instance, the "30x30" goal (protecting 30% of the planet by 2030) could result in a 0.1% decline in global GDP, which is offset by the economic gains from improved ecosystem services. When adjusted for climate mitigation benefits, the net economic loss is even smaller.

• Need for Global Cooperation:
  The success of nature-smart policies depends on global cooperation. The report stresses the importance of creating incentives for countries to work together and implement these policies. It also highlights the need to address political economy challenges within countries to ensure fair distribution of benefits and avoid resistance from affected stakeholders.

• Policy Implications for COP-15 and Post-2020 Framework:
  The findings support the development of a new global biodiversity framework at COP-15. The report encourages the integration of nature-smart policies into national and global strategies, particularly for post-2020 biodiversity goals and post-COVID-19 recovery efforts.

Main Policy Recommendations

• Strengthen global coordination to ensure that all countries benefit from nature-smart policies.
• Reform agricultural subsidies to decouple them from land conversion, thereby reducing the pressure on natural ecosystems.
• Implement domestic and global forest carbon payment schemes to incentivize conservation.
• Increase investment in agricultural R&D to enhance productivity and reduce the need for land expansion.
• Address domestic political economy challenges to ensure that policies are socially inclusive and politically viable.

Key Figures and Data

• Global GDP Loss in Partial Ecosystem Collapse Scenario: $2.7 trillion by 2030.
• Relative GDP Loss in Low-Income Countries: Up to 10%.
• Global GDP Gain from Nature-Smart Policies: Up to $150 billion.
• Natural Land Loss Avoided by Combined Policies: 38% (18 million hectares).
• Natural Land Loss Avoided by Global Forest Carbon Payment: 35% (16 million hectares).
• Economic Benefit from R&D Investment: Up to $148 billion.

Conclusion

This report underscores the economic and environmental importance of nature and the necessity of adopting nature-smart policies to ensure sustainable development. By integrating ecosystem services into economic models, the study provides a framework for understanding the trade-offs and synergies between biodiversity conservation and economic growth. It advocates for a coordinated global response to the biodiversity crisis and highlights the potential for significant economic benefits when nature is valued and protected as a critical asset for development.