Drivers of benthic metacommunity structure along tropical estuaries

Area of Science:

• Ecology
• Marine Biology
• Estuarine Ecology

Background:

• Community structure varies spatially, influenced by environmental gradients.
• Understanding species responses to these gradients is crucial for identifying ecological mechanisms.
• Estuaries, with strong environmental gradients like salinity, are key systems for such studies.

Purpose of the Study:

• To investigate the influence of environmental filters, spatial predictors, and temporal variations on benthic macroinfaunal metacommunity structure.
• To quantify the relative contributions of these factors along salinity gradients in tropical estuaries.
• To test the hypothesis that environmental filters would dominate metacommunity structure.

Main Methods:

• Identified benthic community structures in three estuaries in Todos os Santos Bay, Brazil.
• Employed variation partitioning to assess the impact of environmental, spatial, and temporal predictors.
• Analyzed metacommunity patterns, including nestedness and gradients.

Main Results:

• Benthic metacommunity structure frequently exhibited a quasi-nested pattern.
• Both environmental and spatial predictors significantly influenced metacommunity structure, often jointly.
• Environmental filters did not solely explain the highest proportion of variation as initially hypothesized.

Conclusions:

• Estuarine benthic assemblages displayed a quasi-nested structure, driven by the interplay of environmental and spatial factors.
• Salinity gradients and distance from the sea are likely key drivers of this pattern.
• The findings highlight the complex interactions shaping metacommunity dynamics in estuarine systems.