Marine pollution bulletin最新文献

Extreme climate conditions increasingly threaten worldwide coastal biodiversity. We applied a trait-based approach to quantify the tolerance thresholds of 13 mollusk species from five tropical coastal habitats, using controlled experiments that simulate extreme temperature, salinity, submersion, and desiccation stress. Survival was analyzed in relation to functional traits, including isolation from ambient conditions (presence/absence of shell closure and/or operculum), respiration mode (branchial or pulmonate), shell thickness, and habitat type. Thermal safety margins (TSMs) were also projected under future climate scenarios. Species that possess isolation traits consistently survived across stress conditions. Bivalves generally tolerated higher temperatures and broader salinity ranges than gastropods, and pulmonate gastropods experienced high mortality under both prolonged submersion and desiccation. Desiccation tolerance was strongly associated with the ability to isolate. Thicker shells provided limited protection against extreme temperatures but did not protect taxa with narrow salinity tolerances. Projected TSMs indicated that species from mangrove and oyster-bank habitats will be subject to temperatures that exceed their upper thermal limits before the end of this century. Vulnerability to climate change arises from a combination of functional traits and habitat context. By addressing multiple climate-related variables, i.e., temperature, salinity, inundation, and desiccation, all of which are shifting with global climate change, this study identified combinations of traits that will confer tolerance to tropical mollusks under future conditions and identified taxa that will likely be at risk. This study fills critical data gaps for tropical habitats worldwide and provides a framework for predicting biotic responses to climate extremes.

Increasing nitrogen and phosphorus inputs from the Yangtze River have intensified estuarine eutrophication, posing critical threats to coastal aquatic ecosystems. This study investigates decadal (2011-2022) spatiotemporal dynamics of phytoplankton and zooplankton communities in the Yangtze Estuary, unraveling their responses to environmental perturbations. Phytoplankton communities underwent a significant compositional shift toward improved diversity (higher species richness) despite reduced cell density, transitioning from diatom-dinoflagellate dominance to more diverse assemblages. In contrast, zooplankton communities deteriorated, exhibiting marked declines in species richness and biomass, with copepods, larvae, and coelenterates emerging as dominant taxa. Nutrient analyses revealed interannual decreases in dissolved inorganic nitrogen (DIN) and phosphate (PO₄-P) concentrations, with a slight increase in silicate (SiO₄-Si), and annual average N:P ratios consistently exceeding the Redfield ratio (16:1), indicating persistent phosphorus limitation. Spatially, outer estuarine regions maintained the highest biodiversity and biomass, forming distinct ecological gradients in species richness and evenness compared to inner estuarine zones. Canonical correspondence analysis and Mantel tests revealed strong associations between planktonic assemblages and key environmental drivers: DIN, PO₄-P, SiO₄-Si, and salinity. TITAN (Threshold Indicator Taxa Analysis) further identified critical ecological thresholds with ranges of 0.289-1.360 mg/L for DIN, 0.002-0.023 mg/L for PO₄-P, and 0.685-1.631 mg/L for SiO₃-Si. These findings bridge the gap between plankton community dynamics and nutrient thresholds in large river estuaries, providing mechanistic insights for evidence-based eutrophication management and sustainable coastal ecosystem governance.