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Abstract Seagrass meadows are critically important coastal habitats, but they are undergoing rapid global declines linked to degradation of coastal catchments and the expansion of development in coastal zones, which can lead to increased deposition of terrigenous sediments onto seagrass meadows. In the Asia-Pacific region, which includes the Great Barrier Reef, direct sedimentation effects are recognised as the major threat to seagrass growth and survival. However, tolerance to burial varies among species. Understanding thresholds for burial tolerance at the species-level is therefore critical to effective management of human impacts on seagrass meadows. This research examined the effects of sedimentation on two tropical seagrass species, Zostera muelleri and Halophila ovalis in an experimental mesocosm and field setting. The research suggests that shoot density in these species declines significantly at burial depths of 5–7.5 mm in a mesocosm setting, with very low levels of growth observed above 10 mm burial depth. Fine sediments (including fine sands, silts and clays) appear to have a greater negative effect on shoot density in both species, compared to coarser sandy sediments. In situ , the effect of burial is less pronounced and is likely to be mitigated by a range of factors, including clonal integration. These species also demonstrate different adaptations to burial disturbance, including by resisting burial effects (Z. muelleri) or by regenerating from the buried rhizome after disturbance (H. ovalis). Highlights • We tested the burial tolerance of two tropical seagrasses using estuarine sediments. • In a mesocosm setting, shoot density declines significantly at 5–7.5 mm burial depth. • Growth is very limited at burial depths of 10 mm or greater. • Fine sands and muds (<250 μm) have the strongest suppression effect. • The different adaptations of these species to burial disturbance are discussed. [ABSTRACT FROM AUTHOR]

Seagrass meadows in many parts of the globe are threatened by a range of processes including port development, dredging and land clearing in coastal catchments, which can reduce water clarity and increase sedimentation pressure. As rates of seagrass loss increase, there is an urgent need to understand the potential impacts of development on these critical species. This research compares the effects of shading and burial by fine sand on two seagrass species Zostera muelleri and Halophila ovalis in Port Curtis Bay, an industrial harbour located on the continental margin adjacent to the Great Barrier Reef Heritage Area, Australia. The research finds that shading in combination with burial causes a significant decline in growth rates in both species, but that burial ≥ 10 mm reduces growth rates to a greater extent than shading. The paper concludes by discussing the implications of these findings for port management and impact assessment. [ABSTRACT FROM AUTHOR]

In 1996, the incoming Book Review Editor, Steven R. Brechin, published a note outlining his hopes for the role and the most pressing concerns facing the readership of I Society and Natural Resources i . Steven cataloged an explosion of publications exploring the environment-society nexus. Moreover, as Steven noted, the work we do at the society-environment nexus remains critical. [Extracted from the article]

Conflicts between industrial development and environmental conservation can be particularly acute when such development occurs in the vicinity of World Heritage sites. A key example is the Great Barrier Reef World Heritage Area ( GBRWHA) in northeastern Australia, where a 2012 review by the World Heritage Council found that rapid port development inshore of the coral reef posed significant risks to local marine ecosystems. Such instances pose pressing challenges for decision-makers seeking to manage World Heritage sites for multiple values and needs, including those of key stakeholder groups, such as local communities. There is increasingly a societal expectation that public decision-making takes into account local views and priorities, and that companies seek a 'social license to operate'. This research explored local community attitudes toward port development associated with the export of liquefied natural gas ( LNG) and coal through the GBRWHA. Using data drawn from a survey and interviews, the research examined how a range of geographical factors, including proximity to gas infrastructure and the perceived impacts and risks of development to the local community, economy and environment shape community perceptions of the industry. Findings suggest that local attitudes toward gas and coal terminal development inshore of the GBRWHA are shaped predominantly by community perceptions of environmental impacts and risks associated with such infrastructure, in contrast to a broader public narrative that focuses largely on economic benefits. A complex combination of other factors, including social impacts, personal environmental values, community trust in industry, and equity in decision-making and distribution of the risks and benefits of industrial development also contribute. Placed in a broader, global context, the findings have important implications for public decision-making processes in Australia and elsewhere as they suggest that, for local communities, the perceived impacts of gas development on the environment may overshadow the benefits of industry. [ABSTRACT FROM AUTHOR]