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Townsville, Australia

The Australian Institute of Marine Science is a tropical marine research centre located primarily at Cape Ferguson, North Queensland, Australia. Established in 1972, by the Commonwealth of Australia, the institute's primary function is research for sustainable use and protection of the marine environment. The Institute investigates topics from broad-scale ecology to microbiology.AIMS is committed to the protection and sustainable use of Australia's marine resources. Its research programs support the management of tropical marine environments around the world, with a primary focus on the Great Barrier Reef World Heritage Area, the pristine Ningaloo Marine Park in Western Australia and northwest Australia.AIMS' headquarters are located on a 207-hectare coastal site 50km from Townsville, Queensland, in a scientific zone surrounded by National Park and Marine Reserve. The location was selected because of its proximity to the geographical centre of the Great Barrier Reef and access to clean seawater. This strategic position provides a fast transition from the sea to the laboratory, a key advantage in marine science.Two smaller offices, in Perth, Western Australia, and Darwin, Northern Territory, provide direct links for research partners and clients in these regions. Wikipedia.

Impairment of the photosynthetic machinery of the algal endosymbiont (zooxanthellae) is the proximal driver of the thermal breakdown of the coral-algae symbiosis (coral bleaching). Yet, the initial site of damage, and early dynamics of the impairment are still not well resolved. In this perspective essay, I consider further a recent hypothesis which proposes an energetic disruption to the carbon-concentrating mechanisms (CCMs) of the coral host, and the resultant onset of CO2-limitation within the photosynthetic dark reactions as a unifying cellular mechanism. The hypothesis identifies the enhanced retention of photosynthetic carbon for zooxanthellae (re)growth following an initial irradiance-driven expulsion event as a strong contributing cause of the energetic disruption. If true, then it implies that the onset of the bleaching syndrome and setting of upper thermal bleaching limits are emergent attributes of the coral symbiosis that are ultimately underpinned by the characteristic growth profile of the intracellular zooxanthellae; which is known to depend not just on temperature, but also external (seawater) nutrient availability and zooxanthellae genotype. Here, I review this proposed bleaching linkage at a variety of observational scales, and find it to be parsimonious with the available evidence. Future experiments are suggested that can more formally test the linkage. If correct, the new cellular model delivers a valuable new perspective to consider the future prospects of the coral symbiosis in an era of rapid environmental change, including: (i) the underpinning mechanics (and biological significance) of observed changes in resident zooxanthellae genotypes, and (ii) the now crucial importance of reef water quality in co-determining thermal bleaching resistance. © 2012 Author(s). Source

Alongi D.M.,Australian Institute of Marine Science
Annual Review of Marine Science

Mangroves are ecologically and economically important forests of the tropics. They are highly productive ecosystems with rates of primary production equal to those of tropical humid evergreen forests and coral reefs. Although mangroves occupy only 0.5 of the global coastal area, they contribute 10-15 (24 Tg C y-1) to coastal sediment carbon storage and export 10-11 of the particulate terrestrial carbon to the ocean. Their disproportionate contribution to carbon sequestration is now perceived as a means for conservation and restoration and a way to help ameliorate greenhouse gas emissions. Of immediate concern are potential carbon losses to deforestation (90-970 Tg C y -1) that are greater than these ecosystems' rates of carbon storage. Large reservoirs of dissolved inorganic carbon in deep soils, pumped via subsurface pathways to adjacent waterways, are a large loss of carbon, at a potential rate up to 40 of annual primary production. Patterns of carbon allocation and rates of carbon flux in mangrove forests are nearly identical to those of other tropical forests. Copyright © 2014 by Annual Reviews. Source

Illuminating slices from massive coral skeletons under ultraviolet light can reveal bright luminescent lines in nearshore corals affected by freshwater river flows. The occurrence and intensity of these lines in long-lived corals can then be used to reconstruct past river flow and rainfall, extending the instrumental records of past tropical climate variability considerably. Earlier studies from the Great Barrier Reef, Australia, have used visual assessments of luminescent line intensity to develop semi-quantitative (though potentially subjective) indices of spatial and temporal variations in freshwater flows. Annual visual assessments and relative coral luminescence intensity (measured by fluorescence spectroscopy) and growth variables are first compared for 89 Porites coral colonies from 30 reefs throughout the length and breadth of the GBR. This demonstrates that simple visual assessments can provide useful information, in the absence of quantitative measurements, of this proxy freshwater tracer. The annual range of measured luminescence between the preceding winter minimum and summer maximum, rather than annual average or annual maximum luminescence is shown to be the most robust measure of freshwater flow. Second, from analyses of the coral colony data and over 40-century-long or longer coral core records, attention is drawn to a potential age artefact in annual average and annual maximum measured coral luminescence. These variables show a significant decline through time, similar to the observed decline in average skeletal density. Although the reasons for this decline are unknown, it could compromise interpretation of long-term variations in freshwater flows and subsequent climatic inferences. This artefact does not appear to affect the annual luminescence range which, it is concluded, is a robust proxy for inter-annual variations in river flow and rainfall. © 2010 Springer-Verlag. Source

Wooldridge S.A.,Australian Institute of Marine Science

The consideration of 'mutual benefits' and partner cooperation have long been the accepted standpoint from which to draw inference about the onset, maintenance and breakdown of the coral-algae endosymbiosis. In this paper, I review recent research into the climate-induced breakdown of this important symbiosis (namely 'coral bleaching') that challenges the validity of this long-standing belief. Indeed, I introduce a more parsimonious explanation, in which the coral host exerts a 'controlled parasitism' over its algal symbionts that is akin to an enforced domestication arrangement. Far from being pathogenic, a range of well-established cellular processes are reviewed that support the role of the coral host as an active 'farmer' of the energy-rich photoassimilates from its captive symbionts. Importantly, this new paradigm reposes the deleterious bleaching response in terms of an envelope of environmental conditions in which the exploitative and captive measures of the coral host are severely restricted. The ramification of this new paradigm for developing management strategies that may assist the evolution of bleaching resistance in corals is discussed. © 2010 Wiley Periodicals, Inc. Source

De'Ath G.,Australian Institute of Marine Science

The multinomial diversity model, MDM, is a new method for relating Shannon diversity to complex environmental, spatial, and temporal predictors. It is based on a parameterized formulation of Shannon entropy and diversity, and a novel link between entropy and the log-likelihood of the multinomial model. The MDM relates diversity to the predictors by minimizing the entropy of the estimated species values. Model effects can be expressed as changes in entropy. Entropy can be partitioned within and between sites, species, and models, and changes in entropy can be attributed to model predictors. All entropies translate into diversity for meaningful ecological interpretation. This greatly enhances our capacity to model complex data sets, and yet also provide simple interpretations. By formulating diversity as a statistical model and working in terms of entropy, diversity is simplified both conceptually and analytically, and diversity analyses are extended beyond traditional simple hierarchies of α, β, γ, and measures of turnover. The MDM inherits the properties of generalized linear models, and thus proven methods can be used for model selection and graphical and numerical interpretation. A weighted version of the Shannon diversity model is proposed in order to extend the MDM to non-Shannon diversities. Two example analyses, based on simulated and field data, illustrate the theoretical concepts and the analytical methods. © 2012 by the Ecological Society of America. Source

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