Assessment of sediment porewater toxicity in Biscayne National Park with sea urchin (Lytechinus variegatus) embryos

Abstract

The sea urchin embryo development toxicity test was used to investigate toxicity of the benthic substrate in Biscayne National Park (BISC). Twenty-five sites were selected based upon a high potential for anthropogenic stressor input (e. g., hydrocarbons, personal care products, nutrients, etc.) or proximity to coral reef habitats. We found that sediment interstitial water (porewater) was toxic to urchin embryos at 22 of 25 sites. Healthy sites included two coral reefs (Anniversary Reef and Marker 14 Reef) and Turkey Point Channel. Discrete areas of BISC have highly toxic sediments and the presence of sediment contaminants could negatively impact reproduction, growth and population density of benthic invertebrates, such as corals. Results of the sea urchin embryo development toxicity test can be used as a baseline assessment for monitoring improvements or degradation in ecosystem health and could be a valuable tool to investigate the suitability of degraded habitats for future reef restoration. Since the last comprehensive environmental assessment of BISC was performed in 1999, further investigation into the sources of toxicity at BISC is needed.

Trace element proxies and stable isotopes used to identify water quality threats to elkhorn coral (Acropora palmata) at two national parks in St. Croix, USVI

“…Phosphorus (P) is a nutrient and the concentration in coral skeleton can be used to assess nutrient levels in the surrounding seawater. Sediment porewater from SARI and BUIS analyzed by May and Woodley (2016) also contained greater concentrations of inorganic P at BUIS (up to 367.0 µg/L) compared to SARI (up to 121.0 µg/L). However, sediment composition at SARI and BUIS do not reflect the availability of P. The sediment at BUIS consisted of greater CaCO3, which readily binds inorganic P, rendering it less bioavailable to organisms (Jensen et al, 1998).…”

Acute turbidity exposures with Port of Miami sediments impact Orbicella faveolata tissue regeneration

“…Turbidity was measured using a Hach model 2100P turbidimeter, calibrated with Hach StablCal® formazine standards once daily. Salinity and pH were measured every 24 h. Total ammonia nitrogen was measured in preliminary 96 h sediment tests as previously described (May et al, 2022) to ensure no toxicity occurred from that source. Measurements were below 0.07 mg/L (< 8 µg/L ammonia) for all samples.…”

“…The SUETOX test is a sensitive assay that has been used to gauge toxicity of marine sediment interstitial waters and industrial discharges (Balthis et al, 2018;Carr et al, 2001;Carr et al, 2003;Chapman et al, 1995;May et al, 2022), Since marine sediments can trap and concentrate chemical contaminants such as metals, hydrocarbons, or pharmaceutical products, we exposed sea urchin embryos to the same sediment concentrations used in the coral exposures to understand if residual sediment contaminants could have played a role in the turbidity impacts observed in O.…”