Association Of Seawater Nanoparticle Size Distribution With Diversity Of Marine Plankton

Upon tangential ultrafiltration and asymmetric flow field analyses, seawater nanoparticle size distribution and the associations with the total number of bacteria and plankton diversity were evaluated. Of the nanoparticles in the Jiulong River Estuary, 79% were from 1 to 6 nm (C-1). C-2 (6-20 nm) was correlated with dissolved organic carbon, while C-2 and C-3 (> 20 nm) were associated with dissolved inorganic nitrogen, suggesting that C-2 and C-3 were impacted by biogenic elements. The total number of bacteria was correlated with C-1 and C-3. The correlations of Shannon's diversity index (H') and C-3, richness (d), and C-1 suggested a link of particle size with phytoplankton biodiversity. Significant correlations of the H' of zooplankton and C-3, and of Pielou's evenness index (J) and C-3, suggested C-3 as a primary digestion product of zooplankton. The negative correlations of nano-organic carbon (NOC) with d and J suggested NOC as a carbon source for zooplankton. Biodiversity was associated with seawater nanoparticle size distribution. Biological activities regulated the nanoparticle size distribution, which impacted the estuarine nutrient cycling, in turn affecting the stability and balance of biodiversity. Correlation analysis of the size distribution of seawater nanoparticles and the plankton diversity index provided a potential tool for evaluating ecological effects.