Local Resource Availability and Subsidy Flow Mediate the Effects of Disturbances in Meta-Ecosystems

Area of Science:

• Ecology
• Environmental Science
• Freshwater Biology

Background:

• Human activities intensify disturbance regimes, necessitating understanding of their ecological impacts.
• Landscape heterogeneity, including resource availability and meta-ecosystem flows, can mediate disturbance effects.
• Connected meta-ecosystems are common, yet their role in disturbance response is understudied.

Purpose of the Study:

• To investigate how disturbance intensity affects biomass and community dynamics in connected freshwater protist meta-ecosystems.
• To determine if local resource availability and cross-ecosystem subsidy flow mitigate disturbance impacts.

Main Methods:

• Utilized highly replicated experimental microcosms simulating two-patch meta-ecosystems.
• Manipulated local resource availability (low vs. high carbon release) and meta-ecosystem subsidy flow (detritus and nutrient movement).
• Assessed the effects of varying disturbance intensities on protist community biomass and dynamics.

Main Results:

• High-resource ecosystems maintained biomass regardless of subsidy flow when disturbed.
• Low-resource ecosystems experienced significant biomass decline with increased disturbance.
• Subsidy flow from high-resource to low-resource ecosystems partially mitigated disturbance-induced biomass loss in low-resource patches.

Conclusions:

• Disturbance effects are context-dependent, influenced by local resource levels and inter-ecosystem subsidy flow.
• Spatial heterogeneity and cross-ecosystem subsidies are crucial factors for understanding community responses to disturbance.
• Management strategies for mitigating disturbance impacts should consider landscape heterogeneity and resource subsidies.