Excess seawater nutrients, enlarged algal symbiont densities and bleaching sensitive reef locations: 2. A regional-scale predictive model for the Great Barrier Reef, Australia

Abstract A series of related research studies over 15 years assessed the effects of prawn trawling on sessile megabenthos in the Great Barrier Reef, to support management for sustainable use in the World Heritage Area. These large-scale studies estimated impacts on benthos (particularly removal rates per trawl pass), monitored subsequent recovery rates, measured natural dynamics of tagged megabenthos, mapped the regional distribution of seabed habitats and benthic species, and integrated these results in a dynamic modelling framework together with spatio-temporal fishery effort data and simulated management. Typical impact rates were between 5 and 25% per trawl, recovery times ranged from several years to several decades, and most sessile megabenthos were naturally distributed in areas where little or no trawling occurred and so had low exposure to trawling. The model simulated trawl impact and recovery on the mapped species distributions, and estimated the regional scale cumulative changes due to trawling as a time series of status for megabenthos species. The regional status of these taxa at time of greatest depletion ranged from ∼77% relative to pre-trawl abundance for the worst case species, having slow recovery with moderate exposure to trawling, to ∼97% for the least affected taxon. The model also evaluated the expected outcomes for sessile megabenthos in response to major management interventions implemented between 1999 and 2006, including closures, effort reductions, and protected areas. As a result of these interventions, all taxa were predicted to recover (by 2–14% at 2025); the most affected species having relatively greater recovery. Effort reductions made the biggest positive contributions to benthos status for all taxa, with closures making smaller contributions for some taxa. The results demonstrated that management actions have arrested and reversed previous unsustainable trends for all taxa assessed, and have led to a prawn trawl fishery with improved environmental sustainability.

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The contribution of coral reef-derived dimethyl sulfide to aerosol burden over the Great Barrier Reef: a modelling study

10.5194/acp-2021-507 ◽

2021 ◽

Author(s):

Sonya Fiddes ◽

Matthew Woodhouse ◽

Steve Utembe ◽

Robyn Schofield ◽

Joel Alroe ◽

...

Keyword(s):

Coral Reef ◽

Great Barrier Reef ◽

Time Scales ◽

Dimethyl Sulfide ◽

Regional Scale ◽

Cloud Formation ◽

Barrier Reef ◽

Anthropogenic Aerosol ◽

Daily Time

Abstract. Coral reefs have been found to produce the sulfur compound dimethyl sulfide (DMS), a climatically relevant aerosol precursor predominantly associated with phytoplankton. Until recently, the role of coral reef-derived DMS within the climate system had not been quantified. A study preceding the present work found that DMS produced by corals had negligible long-term climatic forcing at the global-regional scale. However, at sub-daily time scales more typically associated with aerosol and cloud formation, the influence of coral reef-derived DMS on local aerosol radiative effects remains unquantified. The Weather Research and Forecasting – chemistry model (WRF-Chem) has been used in this work to study the role of coral reef-derived DMS at sub-daily time scales for the first time. WRF-Chem was run to coincide with an October 2016 field campaign over the Great Barrier Reef, Queensland, Australia, against which the model was evaluated. After updating the DMS surface water climatology, the model reproduced DMS and sulfur concentrations well. The inclusion of coral reef-derived DMS resulted in no significant change in sulfate aerosol mass or total aerosol number. Subsequently, no direct or indirect aerosol effects were detected. The results suggest that the co-location of the Great Barrier Reef with significant anthropogenic aerosol sources along the Queensland coast prevents coral reef derived-aerosol from having a modulating influence on local aerosol burdens in the current climate.

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NEW FRONTIERS IN ENVIRONMENTAL MANAGEMENT

The APPEA Journal ◽

10.1071/aj95047 ◽

1996 ◽

Vol 36 (1) ◽

pp. 673

Author(s):

R.A. Kenchington ◽

P. Taylor

Keyword(s):

Great Barrier Reef ◽

Resource Use ◽

Regional Scale ◽

Barrier Reef ◽

Multiple Use ◽

Marine Park ◽

Wide Range ◽

Multiple Use Management ◽

Environment And Development ◽

Management Approaches

Historically much of the debate about the environment and development has been conducted as a series of tactical adversarial encounters from which the champions of environment or development emerge as winners or losers.The concept of sustainable development calls for a different approach in which sectors which have traditionally treated each other as opponents work together to achieve mutually acceptable and enduring outcomes. A wide range of societal goals can be met by integrating social and environmental systems through regional scale multiple use planning.This paper discusses the broad applicability of multiple use management approaches through internationally accepted models and by the example of the Great Barrier Reef Marine Park.The paper outlines the complementary responsibilities of the Australian Nature Conservation Agency (ANCA), the Great Barrier Reef Marine Park Authority and other Commonwealth agencies and the scope for them to work with the Petroleum and other industries to develop sustainable multiple use solutions to complex resource use and conservation issues.

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