[Distribution and Correlation Analysis of Microplastic Contamination in Bottom Mud of Zhengzhou Section of the Yellow River].

To investigate the distribution characteristics of microplastics in the middle and lower reaches of the Yellow River， this study selected 18 sites on the Yellow River through Zhengzhou to collect sediment samples， and microplastics were analyzed quantitatively and qualitatively by body-viewing microscopy and Fourier infrared spectroscopy to explore the distribution characteristics of microplastic contamination. The relationship between microplastics and the physicochemical properties of the sediment was examined using Pearson correlation analysis， and the diversity index was used to analyze the potential source of the microplastics. The results showed that the abundance of microplastics in the sediment of the Zhengzhou section of the Yellow River ranged from 533.33 to 2 866.67 n·kg^-1， with a mean value of （1 140.74±496.76） n·kg^-1. The color was dominantly blue， green， and black； the most abundant shape was fibrous； and the dominant particle size was less than 1 mm， with microplastics with a particle size of 0.5-1 mm accounting for the largest proportion of the microplastics. The microplastic polymers differed greatly among the points， but polyethylene terephthalate （PET） was dominant. Their abundance was only weakly correlated with physical and chemical properties of the sediment， but the morphological features showed a degree of correlation. Diversity index analysis showed that the surrounding anthropogenic activities were the main source of microplastics in the Yellow River sediment.