Seagrass species form important marine and estuarine habitats providing valuable ecosystem services and functions. Coastal zones that are increasingly impacted by anthropogenic development have experienced substantial declines in seagrass abundance around the world. Australia, which has some of the world's largest seagrass meadows and is home to over half of the known species, is not immune to these losses. In 1999 a review of seagrass ecosystems knowledge was conducted in Australia and strategic research priorities were developed to provide research direction for future studies and management. Subsequent rapid evolution of seagrass research and scientific methods has led to more than 70% of peer reviewed seagrass literature being produced since that time. A workshop was held as part of the Australian Marine Sciences Association conference in July 2015 in Geelong, Victoria, to update and redefine strategic priorities in seagrass research. Participants identified 40 research questions from 10 research fields (taxonomy and systematics, physiology, population biology, sediment biogeochemistry and microbiology, ecosystem function, faunal habitats, threats, rehabilitation and restoration, mapping and monitoring, management tools) as priorities for future research on Australian seagrasses. Progress in research will rely on advances in areas such as remote sensing, genomic tools, microsensors, computer modeling, and statistical analyses. A more interdisciplinary approach will be needed to facilitate greater understanding of the complex interactions among seagrasses and their environment.

Mangrove soils represent a large sink for otherwise rapidly recycled carbon (C). However, widespread deforestation threatens the preservation of this important C stock. It is therefore imperative that global patterns in mangrove soil C stocks and their susceptibility to remineralization are understood. Here, we present patterns in mangrove soil C stocks across hemispheres, latitudes, countries and mangrove community compositions, and estimate potential annual CO 2 emissions for countries where mangroves occur. Global potential CO 2 emissions from soils as a result of mangrove loss were estimated to be ∼7.0 Tg CO 2 e yr −1 . Countries with the highest potential CO 2 emissions from soils are Indonesia (3,410 Gg CO 2 e yr −1) and Malaysia (1,288 Gg CO 2 e yr −1). The patterns described serve as a baseline by which countries can assess their mangrove soil C stocks and potential emissions from mangrove deforestation.

Seagrasses are well known for the important ecological roles they play in coastal marine waters worldwide. However, the severe rate of decline observed in seagrasses this century is expected to accelerate with climate change. Conservation efforts can be improved by quantifying physiological thresholds of seagrasses and using these estimates in modeling to forecast changes in distribution. This study examines the response of eelgrass (Zostera marina L.) across current temperatures to look for early warning signs of vulnerability and to evaluate the ways we determine critical thresholds for survival. Whole eelgrass ramets, collected from three beds in Morro Bay, California, were used to develop photosynthesis-irradiance (P-I) curves from 10-20°C. Productivity was not affected by changes in temperature when traditionally measured as the light- saturated photosynthetic rate to dark respiration rate (P:R) ratio. However, photosynthesis in light-limited conditions declined at higher temperatures, suggesting a decrease in productivity when coupled with the increased respiration rates observed at higher temperatures. Irradiance thresholds increased with temperature; critical irradiance was the most sensitive to increases in temperature due to the inclusion of overnight energy use, which also increases with temperature. Measurements of root and rhizome respiration, overnight respiration, and variation across eelgrass beds reveal that these are important components to consider when calculating survival thresholds to use in modeling. Differences in physiological responses across beds suggest that some eelgrass beds operate more efficiently than others in current conditions and are likely to be more resilient to the progressing stressors of climate change. Management of eelgrass in the face of climate change will require reliable distribution forecasts, and therefore accurate estimates of physiological thresholds, to guide mitigation and restoration efforts.