Oxygen supersaturation mitigates the impact of the regime of contaminated sediment reworking on sea urchin fertilization process. (June 2020)

• Record Type: Journal Article
• Authors: Limatola, Nunzia; Bertocci, Iacopo; Chun, Jong Tai; Musco, Luigi; Munari, Marco; Caramiello, Davide; Danovaro, Roberto; Santella, Luigia
• Is Part Of: Marine environmental research. Volume 158(2020)
• Publication Date: 2020-06
• Subjects: Fertilization -- Heavy metals -- Hydrocarbons -- Sediment pollution -- Bagnoli-Coroglio brownfield -- Calcium -- Egg cortex -- Sea urchin -- Oxygenation -- Environmental restoration; Marine pollution -- Environmental aspects -- Periodicals; Marine ecology -- Periodicals; Mer -- Pollution -- Aspect de l'environnement -- Périodiques; Écologie marine -- Périodiques; Electronic journals; 577.705
• DOI: 10.1016/j.marenvres.2020.104951
• Languages: English
• ISSNs: 0141-1136

Abstract

Abstract: Dismissed industrial plants with chronic environmental contamination globally affect all levels of biological organization in concert with other natural and anthropogenic perturbations. Assessing the impact of such perturbations and finding effective ways to mitigate them have clear ecological and societal implications. Through indoor manipulative experiments, we assessed here the effects of the temporal regime of reworking of contaminated sediment from the Bagnoli-Coroglio brownfield (Tyrrhenian Sea, Italy) on the fertilization process in Paracentrotus lividus . Adult sea urchins were kept for one month in tanks containing contaminated sediment that was re-suspended according to two temporal patterns of water turbulence differing in the time intervals between consecutive events of agitation (mimicking the storms naturally occurring in the study area) in seawater with natural vs. supersaturated oxygenation levels. At the end of the treatment, gametes were collected and used to test the hypothesis that the regime of contaminated sediment reworking negatively, but reversibly, affects morphological and physiological traits of the fertilized eggs. We found that aggregated events of sediment re-suspension had profound negative effects on gamete interactions and Ca 2+ signaling at fertilization. The same experimental condition also inflicted marked ultrastructural changes in eggs. Importantly, however, such detrimental effects were inhibited by increased oxygenation. By contrast, the regime of sediment re-working with a longer interval between consecutive turbulent events had only marginal effects. Thus, the current and predicted changes of climate-related disturbance appear to modulate the biological effects of chronic contamination in post-industrial areas, suggesting that environmental rehabilitation via restoration of habitat-forming primary producers such as seagrasses or algal canopies could alleviate the pollutants' effects on resident biota. Highlights: Biological effects of chronic contamination and regime of physical disturbance tested in an indoor experiment. Reworking of contaminated sediments by turbulence impaired sea urchin fertilization. Sediment exposure under aggregated turbulence events inhibited gamete interaction and Ca 2+ signaling. Sediment reworking in aggregated turbulence events drastically altered egg ultrastructure. Detrimental effects were all reversed or alleviated by oxygen supersaturation.