Habitat suitability modelling to improve understanding of seagrass loss and recovery and to guide decisions in relation to coastal discharge.

Habitat suitability modelling was used to test the relationship between coastal discharges and seagrass occurrence based on data from Adelaide (South Australia). Seven variables (benthic light including epiphyte shading, temperature, salinity, substrate, wave exposure, currents and tidal exposure) were simulated using a coupled hydrodynamic-biogeochemical model and interrogated against literature-derived thresholds for nine local seagrass species. Light availability was the most critical driver across the study area but wave exposure played a key role in shallow nearshore areas.

Web-based internet searches for digital health products in the United Kingdom before and during the COVID-19 pandemic: a time-series analysis using app libraries from the Organisation for the Review of Care and Health Applications (ORCHA).

Objectives: To explore if consumer interest in digital health products (DHPs), changed following the COVID-19 pandemic and the lockdown measures that ensued.

Design: Retrospective time-series analysis of web-based internet searches for DHPs in the UK, split over two periods, pre-COVID-19 lockdown (January 2019-23 March 2020) and post-COVID-19 lockdown (24 March 2020-31 December 2020).

Setting: The UK.

Fate and dynamics of metal precipitates arising from acid drainage discharges to a river system.

Neutralisation of acid drainage creates metal-rich precipitates that may impact receiving water bodies. This study assessed the fate of over seven years of acid drainage discharges on the sediments of the lower River Murray (Australia), including the potential for periodic water anoxia to enhance risk via reductive dissolution of amorphous (Fe, Mn and co-precipitated and bound metal) oxide phases. With the exception of one site with restricted water exchange, elevated reducible/reactive metal(oid) (Fe, Ni, As, Co, Zn) concentrations were only observed in the localised wetland-riparian area within approximately 100 m of the discharges.

Chlorination of Microcystis aeruginosa: toxin release and oxidation, cellular chlorine demand and disinfection by-products formation.

Direct chlorination of toxic cyanobacteria cells can occur at various stages of treatment. The objectives of this work are to determine and model the extent of Microcystis aeruginosa cells lysis, toxins and organic compounds release and oxidation, and quantify the subsequent disinfection by-products formation. Chlorine exposure (CT) values of 296 and 100 mg min/L were required to obtain 76% cell lysis and oxidation of released cell-bound toxins at levels below the provisional World Health Organisation guideline value (1 μg/L MC-LR).