Urbanization and Spatial Aggregation Impair Multifunctionality in Urban Vacant Lots

Area of Science:

• Urban ecology
• Ecosystem science
• Conservation biology

Background:

• Urban shrinkage is increasing vacant lots, creating opportunities for biodiversity and ecosystem multifunctionality.
• Relationships between biodiversity and ecosystem multifunctionality in vacant lots are understudied.

Purpose of the Study:

• To investigate the influence of environmental factors and ecological communities on ecosystem functions and multifunctionality in urban vacant lots.
• To analyze the direct and indirect effects of urbanization and vacant lot spatial configuration on ecosystem multifunctionality.

Main Methods:

• Studied 69 vacant lots in Yokohama, Japan, measuring environmental factors, ecosystem functions, and plant/microbial diversity.
• Employed structural equation modeling and generalized linear mixed models to analyze relationships.
• Used a multiple-threshold approach to assess trade-offs and synergies among ecosystem functions.

Main Results:

• Environmental factors were dominant drivers of ecosystem functions, with soil moisture positively influencing functions and multifunctionality.
• Spatial aggregation of vacant lots negatively impacted functions, mediated by plant richness and fungal composition.
• Urbanization negatively affected ecosystem functions and multifunctionality, especially at higher multifunctionality thresholds.

Conclusions:

• Urban vacant lot multifunctionality is shaped by environmental factors and mediated by diverse taxa.
• Strategic spatial configuration of vacant lots is crucial for balancing biodiversity and ecosystem multifunctionality in shrinking cities.
• Urban planning must consider these factors to optimize vacant lot potential in declining urban areas.