Global change factors differ in effect when acting alone and in a multi-factor background.

Area of Science:

• Environmental Science
• Soil Science
• Ecology

Background:

• Ecosystems are increasingly impacted by multiple global change factors.
• Urban soils are particularly vulnerable to a combination of stressors including heat, drought, road salt, nitrogen deposition, surfactants, and microplastics.
• The combined effects of these stressors can be unpredictable and differ significantly from their individual impacts.

Purpose of the Study:

• To identify which individual global change factors have the most negative effects in a multifactorial urban soil context.
• To understand the impact of removing specific stressors from a complex mixture of environmental factors.

Main Methods:

• A subtractive experimental design was employed.
• Single-factor addition treatments were compared to treatments where a specific factor was removed from a multi-factor context.
• Soil properties and biological processes were assessed.

Main Results:

• The effects of individual factors varied, ranging from negative to positive or mixed.
• Removing stressors from a multi-factor context generally led to improvements in soil properties and biological processes.
• Resource-related factors enhanced microbial activity in isolation but not in the multi-factor scenario.

Conclusions:

• The combined impact of environmental stressors often diverges from their individual effects.
• Mitigating factors with the strongest negative influence in multi-stressor urban soil contexts is crucial for effective restoration.
• Prioritizing interventions based on multi-stressor impacts, not just isolated effects, is recommended for ecological restoration efforts.