Distribution pattern of meiofauna assemblages along an environment gradient on the coast of the Yellow and Bohai Seas

This study investigated the influence of both natural and anthropogenic factors on meiofauna assemblages along the coasts of the Yellow Sea (YS) and Bohai Sea (BS). Over 300 abiotic and biotic samples were collected from 101 sites, categorized by land use (agricultural, industrial, municipal, no use), region (southern, central, northern China, and Korea), and habitat (fresh, brackish, saline). Meiofauna densities and assemblage structures varied significantly across all regions, habitats, and land-use types, while diversity differed mainly by region. A distance-based linear model identified key environmental drivers-grain size, heavy metals, total nitrogen, pH, delta 15N, salinity, and dissolved oxygen-that collectively explained approximately 26 % of the variation in meiofauna distribution. These findings enhance understanding of how environmental gradients and human impacts shape benthic ecosystems. The study provides essential ecological information for assessing sediment quality and informs strategies for mitigating marine pollution in the YS and BS regions.