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The Hawaiian Archipelago experienced a moderate bleaching event in 2019—the third major bleaching event over a 6-year period to impact the islands. In response, the Hawai'i Coral Bleaching Collaborative (HCBC) conducted 2,177 coral bleaching surveys across the Hawaiian Archipelago. The HCBC was established to coordinate bleaching monitoring efforts across the state between academic institutions, non-governmental organizations, and governmental agencies to facilitate data sharing and provide management recommendations. In 2019, the goals of this unique partnership were to: 1) assess the spatial and temporal patterns of thermal stress; 2) examine taxa-level patterns in bleaching susceptibility; 3) quantify spatial variation in bleaching extent; 4) compare 2019 patterns to those of prior bleaching events; 5) identify predictors of bleaching in 2019; and 6) explore site-specific management strategies to mitigate future bleaching events. Both acute thermal stress and bleaching in 2019 were less severe overall compared to the last major marine heatwave events in 2014 and 2015. Bleaching observed was highly site- and taxon-specific, driven by the susceptibility of remaining coral assemblages whose structure was likely shaped by previous bleaching and subsequent mortality. A suite of environmental and anthropogenic predictors was significantly correlated with observed bleaching in 2019. Acute environmental stressors, such as temperature and surface light, were equally important as previous conditions (e.g. historical thermal stress and historical bleaching) in accounting for variation in bleaching during the 2019 event. We found little evidence for acclimation by reefs to thermal stress in the main Hawaiian Islands. Moreover, our findings illustrate how detrimental effects of local anthropogenic stressors, such as tourism and urban run-off, may be exacerbated under high thermal stress. In light of the forecasted increase in severity and frequency of bleaching events, future mitigation of both local and global stressors is a high priority for the future of corals in Hawai'i. [ABSTRACT FROM AUTHOR]

In order to produce 1000 kg of leather, it is estimated of 85% of chemical input, used by European tanning plants, is discharged as contaminant. Among of them, Cr (VI), this is a toxic compound of easy adsorption. In that sense, the present work is focused on the removal of Cr (VI) in synthetic solution prepared from Cr (VI) estimated concentration found in wastewater sample discharged by tanning industries (Cr (VI): 32,6 mg/kg). Thus, five filters packed with orange (Citrus sinensis) and plantain (Musa AAB) peels were used in laboratory scale (Fa: 100% orange, Fb: 70% orange/30% plantain, Fc: 50% orange /50% plantain, Fd: 30% orange /70% plantain y Fe: 100% plantain). The main results show that among filters with the best performance in adsorption was Fd. Such filter had a removal efficiency of 93%, compare to Fa: 73%, Fb: 90%, Fc: 86% y Fe: 82%. Additionally, the adsorption constants found were between 96 and 132 mg Cr (VI)/gadsorb. Therefore, the combined bioadsorbents (plantain/orange peels) could be highly recommended for Cr (VI) removal in tanning effluents. [ABSTRACT FROM AUTHOR]