Effects of multiple stressors on marine shallow-water sediments: Response of microalgae and meiofauna to nutrient–toxicant exposure

摘要: Abstract Two types of common stressors acting simultaneously on shallow coastal ecosystems include increased anthropogenic nutrient loading and exposure to toxicants. Nutrients (inorganic nitrogen phosphorus) the polyaromatic hydrocarbon (PAH) pyrene were added singly in combination, study combined effects nutrients toxicants base food web a shallow-water illuminated sediment. The microbenthic community natural sieved, sediment was used flow-through laboratory experiment lasting 28 days. Variables measured included benthic microalgal meiofaunal biomass composition, grazing rates. hypotheses that (i) affects meiofauna their rate, resulting biomass, (ii) depend status, as found previous mesocosm experiments. Our results showed low, environmentally realistic concentration had general negative effect rates, although major taxonomical groups differed response. A concomitant increase suggested cascading primary producers. Whether there significant interaction between status depended variable measured. While toxicant total chlorophyll content composition algal (based cell counts) did not. We only partial support for our specific hypothesis greater when concentrations high. mode nutrient–toxicant appeared vary with variable; non-additive (antagonistic or synergistic) more than additive effects, but some could also be interpreted according comparative model. This apparent variation highlights complexity interactions — multiple marine environment, emphasizing need consider both structural functional variables assessing stressor interactions. Moreover, presence potential indirect, web-mediated underlines test multiple-stressor using multitrophic communities.