Glyphosate is one of the most widely applied herbicides globally but its persistence in seawater has not been reported. Here we quantify biodegradation glyphosate using standard "simulation" flask tests with native bacterial populations and coastal from Great Barrier Reef. The half-life for at 25 °C low-light was 47 days, extending to 267 days dark 315 31 °C, which longest reported this herbicide. AMPA, microbial transformation product glyphosate, detected under all conditions, confirming...

Crustose coralline algae (CCA) are a critical component of coral reefs as they accrete carbonate for reef structure and act settlement substrata many invertebrates including corals. CCA host diversity microorganisms that can also play role in metamorphosis processes. Although the sensitivity to ocean acidification (OA) is well established, response their associated microbial communities reduced pH increased CO2 was previously not known. Here we investigate CCA-associated biofilms OA...

Abstract Key calcifying reef taxa are currently threatened by thermal stress associated with elevated sea surface temperatures (SST) and reduced calcification linked to ocean acidification (OA). Here we undertook an 8 week experimental exposure near-future climate change conditions explored the microbiome response of corals Acropora millepora Seriatopora hystrix , crustose coralline algae Hydrolithon onkodes foraminifera Marginopora vertebralis Heterostegina depressa urchin Echinometra sp....

In order to examine the potential interactive pressures of local pollution and global climate change, we exposed corals crustose coralline algae (CCA) three agricultural photosystem II (PSII) herbicides at four temperatures (26–32°C). The coral Acropora millepora was 3‐ 10‐fold more sensitive than CCA Neogoniolithon fosliei . While photosynthesis not affected by herbicide concentrations used (< 1 μg L −1 ), 31°C 32°C alone significantly inhibited photosynthetic efficiency (ΔF:F ′ m )...

Coastal waters of the Great Barrier Reef (GBR) are contaminated with agricultural pesticides, including photosystem II (PSII) herbicides which most frequently detected at highest concentrations. Designed to control weeds, these equally potent towards non-target marine species, and close proximity seagrass meadows flood plumes has raised concerns that seagrasses may be species threatened by from runoff. While previous work identified effects PSII on photophysiology, growth mortality in...

Understanding the sedimentation and turbidity thresholds for corals is critical in assessing potential impacts of dredging projects tropical marine systems. In this study, we exposed two species coral sampled from offshore locations to six levels total suspended solids (TSS) 16 weeks laboratory, including a 4 week recovery period. Dose-response relationships were developed quantify lethal sub-lethal corals. The sediment treatments affected horizontal foliaceous (Montipora aequituberculata)...

Abstract Risks posed by oil spills to coral reefs are difficult evaluate, partially due the absence of studies that adequately assess toxicity relevant reef species. Here we experimentally tested acute condensate, representing a fraction light crude oil, ( Acropora tenuis ) and sponge Rhopaloeides odorabile larvae. The metamorphosis larvae was inhibited at total petroleum aromatic hydrocarbon (TPAH) concentrations water accommodated fractions (WAF) as low 103 μg l −1 , similar detected in...

Microorganisms form symbiotic partnerships with a diverse range of marine organisms and can be critical to the health survival their hosts. Despite importance these relationships, sensitivity microbes ocean acidification (OA) is largely unknown this needs redressed adequately predict ecosystem resilience in changing climate. We adopted profiling approach explore associated coral reef biofilms representatives three ecologically important calcifying invertebrate phyla [corals, foraminifera...

Abstract Photosystem II herbicides are transported to inshore marine waters, including those of the Great Barrier Reef and usually detected in complex mixtures. These inhibit photosynthesis, which can deplete energy reserves reduce growth seagrass, but toxicity some these seagrass is unknown combined effects multiple on has not been tested. Here we assessed acute phytotoxicity 10 PSII Halophila ovalis over 24 and/or 48 h. Individual exhibited a broad range toxicities with inhibition...

Herbicides are detected year-round in marine waters, including those of the World Heritage listed Great Barrier Reef (GBR). The few previous studies that have investigated herbicide persistence seawater generally reported half-lives order months, and several were too short to detect significant degradation. Here we eight herbicides commonly GBR or its catchments standard OECD simulation flask experiments, but with aim mimic natural conditions similar found on (i.e., relatively low...

Abstract Coral reef ecosystems are declining and may not recover under future climate scenarios without intervention. Seeding reefs with corals bred in aquaculture is a promising restoration intervention; however, early coral recruits (spat) vulnerable to overgrowth by benthic algae maximizing their survival essential for the feasibility of large-scale breeding operations. This study investigated optimal light quality intensity spat growth presence algal communities typically used induce...

Abstract Sexual propagation of corals is a promising strategy for coral restoration, but one the main challenges high mortality spat due to competitive interactions with macroalgae during early life history stages. Optimising properties settlement substrates such as material types and surface roughness has potential improve survival by limiting recruitment growth macroalgae. In this study, we assessed effects modifying across three different tile materials (alumina-based ceramic, calcium...

Widespread contamination of nearshore marine systems, including the Great Barrier Reef (GBR) lagoon, with agricultural herbicides has long been recognised. The fate these contaminants in environment is poorly understood but detection photosystem II (PSII) GBR year-round suggests very slow degradation rates. Here, we evaluated persistence a range commonly detected water under field-relevant concentrations and conditions. Twelve-month experiments were conducted large open tanks, different...

Abstract Herbicide contamination of nearshore tropical marine ecosystems is widespread and persistent; however, risks posed by most ‘alternative’ herbicides to microalgae remain poorly understood. Experimental exposures the important but understudied Rhodomonas salina seven individual Photosystem II (PSII) inhibitor (diuron, metribuzin, hexazinone, tebuthiuron, bromacil, simazine, propazine) led inhibition effective quantum yield (ΔF/F m ′) subsequent reductions in specific growth rates...

Pesticides are ubiquitous in the catchments of Great Barrier Reef (GBR) and regularly discharge into nearshore waters. Effective management pesticides requires suitable water quality guideline values (WQGVs), further ecotoxicological data for many needed to improve reliability environmental risk assessments. To help address this issue, toxicity thresholds were determined two species tropical marine microalgae Tisochrysis lutea Tetraselmis sp. a suite herbicides detected GBR. Photosystem II...

Abstract Coral reefs are at risk of exposure to petroleum hydrocarbons from shipping spills and uncontrolled discharges during extraction. The toxicity can substantially increase in the presence ultraviolet radiation (UVR), therefore shallow coral reef environments may be particularly hazardous species. Here we investigated sensitivity larvae ( Acropora tenuis ) dissolved heavy fuel oil (HFO) diesel absence UVR. Larval settlement success decreased with increasing concentrations HFO,...

Abstract Conventional photosystem II (PSII) herbicides applied in agriculture can pose significant environmental risks to aquatic environments. In response the frequent detection of these Great Barrier Reef (GBR) catchment area, transitions towards ‘alternative’ are now widely supported. However, water quality guideline values (WQGVs) for alternative lacking and their potential ecological impacts on tropical marine species generally unknown. To improve our understanding posed by some under...

Tropical seagrasses are at their highest risk of exposure to photosystem II (PSII) herbicides when elevated rainfall and runoff from farms transports these toxicants into coastal habitats during summer, coinciding with periods temperature. PSII herbicides, such as diuron, can increase the sensitivity corals thermal stress, but little is known potential for impact optima tropical seagrass. Here we employed a well-plate approach experimentally assess effects diuron on photosynthetic...

Abstract The toxicity of herbicide degradation (transformation) products is rarely taken into account, even though these are commonly detected in the marine environment, sometimes at concentrations higher than parent compounds. Here we assessed potential contribution by transformation five photosystem II herbicides to coral symbionts ( Symbiodinium sp.), green algae Dunaliella sp., and prawn Penaeus monodon ) larvae. Concentration-dependent inhibition photosynthetic efficiency ∆F/F m ′) was...

This experimental study aimed to determine the acceptability of scallop kropek as aroma, color, flavor, texture and general well its in three formulations made up 1/4 cup paste ¾ tapioca flour (Formulation A); ½ B; and, ¼ C). It also significant difference acceptability. The respondents this were 15 HRM students, Home makers Kropek vendors who responded a sensory evaluation score sheet using modified five-point hedonic scale research instrument. statistical tool used was mean standard...

Photosystem II (PSII) herbicides have been detected in nearshore tropical waters such as those of the Great Barrier Reef and may add to pressure posed by runoff containing sediments nutrients threatened seagrass habitats. There is a growing number studies into potential effects on seagrass, generally using large experimental setups with potted plants. Here we describe successful development an acute 12-well plate phytotoxicity assay for PSII herbicide Diuron isolated Halophila ovalis leaves....

Abstract Coal is a principal fossil fuel driving economic and social development increases in global coal shipments have paralleled expansion of the industry. To identify potential harm associated with chronic marine contamination, three taxa abundant tropical ecosystems (the coral Acropora tenuis , reef fish Acanthochromis polyacanthus seagrass Halodule uninervis ) were exposed to five concentrations (0–275 mg l −1 suspended dust (<63 μm) over 28 d. Results demonstrate that exposure can...

Abstract Over 30 herbicides have been detected in catchments and waters of the Great Barrier Reef (GBR) their toxicity to key tropical species, including coral endosymbiotic algae Symbiodiniaceae, is not generally considered current water quality guideline values (WQGVs). Mutualistic symbionts family Symbiodiniaceae are essential for survival scleractinian corals. We tested effects nine GBR-relevant on photosynthetic efficiency (ΔF/F m ′) specific growth rate (SGR) over 14 days cultured...

The Great Barrier Reef (GBR) is threatened by climate change and local pressures, including contaminants in nearshore habitats. This study investigated the combined effects of a GBR-relevant contaminant, herbicide diuron, under current two future scenarios on coral Acropora millepora. All physiological responses tested (effective quantum yield (ΔF/Fm′), photosynthesis, calcification rate) were negatively affected with increasing concentrations diuron. Interactive between diuron observed for...