Industrial impacts on eastern Amazon streams assessment with benthic EPT community, leaf litter decomposition and associated fauna

Area of Science:

• Ecology
• Environmental Science
• Conservation Biology

Background:

• Stream ecosystems are sensitive to land-use change, but tropical stream impacts are understudied.
• Industrialization, urbanization, and poor sanitation disrupt aquatic habitats and functions globally.
• Eastern Amazonian rivers face increasing anthropogenic pressures.

Purpose of the Study:

• To assess the impacts of industrial activities on tropical stream ecosystems in the eastern Amazon.
• To evaluate structural and functional indicators, including benthic macroinvertebrates and leaf litter decomposition.
• To compare impacted industrial streams with unimpacted control streams across seasons.

Main Methods:

• Studied ten eastern Amazonian rivers, comparing five impacted by industrial activities with five control rivers.
• Assessed benthic macroinvertebrate communities, focusing on Ephemeroptera, Plecoptera, and Trichoptera (EPT).
• Measured leaf litter decomposition rates of Goupia glabra, examining microbial and faunal contributions in dry and rainy seasons.

Main Results:

• Industrial streams showed significantly lower EPT abundance and reduced macroinvertebrate colonization of leaf litter.
• Microbial decomposition rates were similar, but total decomposition was higher in control streams, indicating fauna's role.
• Impacts persisted across seasons, with some trends more pronounced during the dry season.

Conclusions:

• Industrial activities, urbanization, and inadequate sanitation severely degrade tropical stream biodiversity and ecological functioning.
• Associated fauna play a crucial role in leaf litter decomposition in these ecosystems.
• Integrated conservation strategies are vital to manage cumulative land-use impacts and preserve Amazonian stream ecosystem services.