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Australia's navy told to be more visible near resource projects.

Australian scientists have identified causes of a rapid warming in the upper subtropical oceans of the Southern Hemisphere.

Scientists know that low-oxygen dead zones are growing worldwide. New research sheds light on what that will mean for estuary systems if trends continue.

Dead mangrove forests in northern Australia found to emit more methane than live trees.

New study confirms the oceans are warming rapidly.

In the Middle East, reliance on desalination comes at a high cost.

Quantitatively assessing the porewater dissolved inorganic carbon (DIC) cycling in methane-enriched marine sediments is crucial to understanding the contributions of different carbon sources to the global marine carbon pool. In this study, Makran accretionary wedge was divided into Zone 1 (high methane flux area) and Zone 2 (background area). Porewater geochemical compositions (Cl-, SO42-, NH4+, Mg2+, Ca2+, Ba2+, DIC and δ13C-DIC) and a reaction-transport model were used to determine the DIC source and calculate the DIC flux through carbonate precipitation and releasing into overlying seawater in sediments. Zone 1 is characterized by the shallower depth of sulfate-methane transition (SMT), where most of porewater sulfate was consumed by anaerobic oxidation of methane (AOM). In contrast, a relatively low flux of methane diffusion in Zone 2 results in a deeper SMT depth and shallow sulfate is predominantly consumed by organoclastic sulfate reduction (OSR). Based on the porewater geochemical profiles and δ13C mass balance, the proportions of porewater DIC originating from methane were calculated as 51% in Zone 1 and nearly 0% in Zone 2. An increase of porewater DIC concentration leads to authigenic carbonate precipitation. Solid total inorganic carbon (TIC), X-ray diffractometry (XRD) and scanning electron microscopy (SEM) analysis display that carbonate content increases with depth and aragonite appears at or below the depths of SMT. Meanwhile, the flux of DIC released from sediments calculated by the reaction-transport model is 51.3 ~ 90.4 mmol/m2·yr in Zone 1, which is significantly higher than that in Zone 2 (22.4 mmol/m2·yr). This study demonstrates that AOM serves as the dominant biogeochemical process regulating the porewater DIC cycle, which has an important impact on the authigenic carbonate burial and the seawater carbonate chemistry.

Cyclone intensifies, Australia's iron ore mines brace.

Surfing geologist applies science to shark risk.

Marine parks need to cover large swathes of ocean, but they also need to cover the right areas if they are to deliver the best conservation. New research off Australia's northwest suggests how.

Marine parks need to cover large swathes of ocean, but they also need to cover the right areas if they are to deliver the best conservation. New research off Australia's northwest suggests how.