Ecosystem services response to urbanization in metropolitan areas: Thresholds identification

Area of Science:

• Urban ecology and environmental science, focusing on the quantitative assessment of ecosystem services.
• Spatial analysis and landscape ecology, examining the geographical distribution of ecosystem services.

Background:

• Ecosystem services are crucial indicators of urbanization's ecological impact.
• Previous research indicates a causal link between urbanization and ecosystem service degradation, but thresholds and non-linear dynamics remain unclear.

Purpose of the Study:

• To quantify four key ecosystem services and total ecosystem services (TES) in Beijing's peri-urban area.
• To identify advantageous and disadvantageous areas for ecosystem services.
• To detect the impact thresholds of urbanization (population density, GDP density, land proportion) on TES.

Main Methods:

• Quantification of soil conservation, carbon sequestration, water yield, and food production services.
• Identification of ecosystem service advantageous areas using spatial analysis.
• Application of piecewise linear regression to determine TES response and thresholds to urbanization drivers.

Main Results:

• Total ecosystem services (TES) exhibit spatial heterogeneity, with higher values in the north and west, and lower values in the southeast.
• Population and economic urbanization show thresholds (229 person/km², 107.15 million yuan/km²) beyond which TES declines rapidly.
• Land urbanization demonstrates a direct negative linear relationship with TES, indicating a more pronounced impact than population or economic factors.

Conclusions:

• Urban ecological sustainability requires balancing economic and population growth with controlled land urbanization.
• The urban function extended zone experiences the most severe negative impacts of urbanization on TES.
• Strategic urban planning should prioritize slowing land urbanization to minimize ecosystem service degradation.