Impacts of cascade damming density on aquatic multi-trophic microbial communities and food web structure in the upper Yellow River

Key Points

• This research analyzes how varying intensities of cascade damming affect multi-trophic microbial communities and their food web structure in the upper Yellow River.
• Comparative analysis of three river sections with varying levels of dam interference: natural, weak, and strong.
• Utilized eDNA technology to assess diversity and community composition of microorganisms across different trophic levels.
• Partial Mantel tests to evaluate relationships between dam operational years and microbial community structures.
• Significant nutrient retention effects were observed in cascade dams, with a complex 'inverted U-shape' response in environmental heterogeneity.
• Bacterial community alpha diversity increased with higher dam interference, whereas higher trophic groups displayed delayed responses.
• Community structures varied significantly among river sections, with bacteria showing the greatest variability, especially between natural and strongly interfered sections.