BCL alumni and graduates

Thesis

A deeper investigation on seaweed potential for carbon sequestration

Global climate change has brought several negative impacts on the environment as well as on varied aspect of communities’ livelihoods. Meanwhile, many researchers have investigated the possibility of ameliorative effort against its effects on both people and the environment. Seaweed is one of a scientifically proven way in carbon capture and storage (CCS) concept which has been taking notice of many researchers. However, some argue whether or not seaweed can be considered for carbon sequestration which is a long-term carbon storage. Ellyn investigated the potential of seaweed carbon to be stored in sea bottom sediment for a long period of time. This will develop a suite of biomarkers that allow both detection and quantification of seaweed carbon in sediments. Moreover, understanding the environmental conditions that may affect carbon sequestration is one of the important targets of this study. Mesocosm experiment would be conducted with respect to the recalcitrant carbon content in seaweed which could restrain the seaweeds decomposition process over time. Finally, the findings will disclose the potential of seaweed as an essential part of “blue carbon” system.

Selected publications

Erlania and I Nyoman Radiarta. 2015. The use of seaweeds aquaculture for carbon sequestration: a strategy for climate change mitigation. Journal of Geodesy and Geomatics Engineering, 2: 109-115.

Erlania and I Nyoman Radiarta. 2015. Distribution of wild seaweeds based on sea bottom characteristics along reef-flat area in Labuhanbua waters, West Nusa Tenggara: management strategy for aquaculture development. Aquaculture Research Journal, 10 (3): 449-45

Thesis

Alejandro’s research focused on analysis of coastal marine habitats in order to quantify the economic and ecological services provided by these ecosystems. He was also interested on ecological and habitat modelling of marine species of economic and conservational interest, in order to help to predict their distribution patterns in the light of changing bio-physical conditions due to climate or other anthropogenic changes.

The global aim of his PhD thesis was to develop local valuations of coastal ecosystem services for marine habitats, and communicate these to stakeholders using spatial maps and other media. His research aimed to quantify the benefits people gain from natural systems, to evaluate the potential impacts of alternative management scenarios, and to perform assessments of the trade‐offs between development and different ecosystem services in southern Australia.

Thesis

Seagrass restoration in Southeast Australia

Oliver’s project focusses on methodologies to best restore intertidal Zostera muelleri seagrass meadows in Western Port Bay (Southeast Australia). Oliver’s work will be completed in partnership with Yi Mei Tan (another BCL member) and will utilise interdisciplinary techniques combining ecology, environmental science, and spatial modelling to identify areas suitable for restoration and how best to approach such restoration. Substantial losses of seagrass in Western Port have occurred in the past 30-50 years with minimal evidence of natural recovery. Oliver’s research will work to reverse these trends by providing insight on the mechanisms preventing natural recovery and how to mitigate these influences.

Selected publications

Dalby, O., Pucino, N., Tan, Y.M., Jackson, E.L., Macreadie, P.I., Coleman, R.A., Young, M.A., Ierodiaconou, D. and Sherman, C.D. 2022. Identifying spatio-temporal trends in seagrass meadows to inform future restoration. Restoration ecology e13787.

Tan, Y.M., Dalby, O., Kendrick, G.A., Statton, J., Sinclair, E.A., Fraser, M.W., Macreadie, P.I., Gillies, C.L., Coleman, R.A., Waycott, M. and Van Dijk, K.J., 2020. Seagrass restoration is possible: Insights and lessons from Australia and New Zealand. Frontiers in Marine Science, 7, p.617.

Thesis

Seagrass restoration: Development of methods for the recovery of intertidal seagrass meadows.

Yi Mei’s project involved the development of restoration and recovery methodology for intertidal seagrass meadows in Western Port Bay (South Eastern Australia). Seagrasses represent a major marine habitat in Western Port Bay, but has seen significant declines over the last 40-50 years. Despite efforts to improve overall conditions within the bay, natural recovery has been slow and some areas have shown no sign of recovery despite improved water quality. Yi Mei’s research explored different tools and techniques, through a combination of field-based trials and mesocosm experiments, to facilitate re-establishment of seagrasses in areas where natural recovery has not occurred and assist more rapid recovery in areas where natural recovery is occurring slowly.   

Selected publications

Dalby, O., Pucino, N., Tan, Y.M., Jackson, E.L., Macreadie, P.I., Coleman, R.A., Young, M.A., Ierodiaconou, D. and Sherman, C.D (2022) Identifying spatio-temporal trends in seagrass meadows to inform future restoration. Restoration ecology e13787.

Tan, Y.M., Dalby, O., Kendrick, G.A., Statton, J., Sinclair, E.A., Fraser, M.W., Macreadie, P.I., Gillies, C.L., Coleman, R.A., Waycott, M. and Van Dijk, K.J., (2020) Seagrass restoration is possible: Insights and lessons from Australia and New Zealand. Frontiers in Marine Science, 7, p.617.

Fortes, M. D., Ooi, J. L. S., Tan, Y. M., Prathep, A., Bujang, J. S., & Yaakub, S. M. (2018). Seagrass in Southeast Asia: a review of status and knowledge gaps, and a road map for conservation. Botanica Marina, 61, 269-288.

Tan, Y. M., Saunders, J. & Yaakub, S. (2018). A proposed decision support tool for prioritising conservation planning of Southeast Asian seagrass meadows: combined approaches based on ecosystem services and vulnerability analyses. Botanica Marina, 61, pp. 305-320

Thesis

Decommissioning Offshore Infrastructure

Australia, together with numerous countries with offshore oil and gas (O&G) activities nearing their end of life, have a substantial and escalating decommissioning dilemma –– to remove or not to remove, and which decommissioning option provide the best environmental outcomes?

Sarah’s PhD research determined whether there is sufficient knowledge and technology, together with supportive regulations, already in place in order for Australia’s offshore O&G operators and regulators to be able to make this determination. And, if/where there was not, detailed recommendations to bridge such gaps based on a wide range of stakeholder views, research, and global best practices.

Selected publications

Watson, Sarah M. “Greenhouse gas emissions from offshore oil and gas activities—Relevance of the Paris Agreement, Law of the Sea, and Regional Seas Programmes” Ocean & Coastal Management 185 (2020): 104942

Thesis

Herbivores as ecosystem engineers in tropical seagrass meadows: Grazing impacts on meadow structure and ecosystem service delivery

Abbi’s work investigated how herbivores affect seagrass meadows around the Great Barrier Reef to understand their impact on the provision of ecosystem services, specifically focusing on how carbon storage in seagrass meadows can be modified by grazing activity. Her research will inform management measures that seek to maintain ecosystem function and understand potential trade-offs in ecosystem service delivery.

Selected publications

Scott, A. L., York, P. H., & Rasheed, M. A. (2021). Spatial and Temporal Patterns in Macroherbivore Grazing in a Multi-Species Tropical Seagrass Meadow of the Great Barrier Reef. Diversity, 13(1), 12.

Scott, A. L., York, P. H., & Rasheed, M. A. (2021). Herbivory has a major influence on structure and condition of a Great Barrier Reef subtropical seagrass meadow. Estuaries and Coasts, 44(2), 506-521.

Scott, A. L., York, P. H., & Rasheed, M. A. (2020). Green turtle (Chelonia mydas) grazing plot formation creates structural changes in a multi-species Great Barrier Reef seagrass meadow. Marine Environmental Research, 162, 105183.

Thesis

Microbiology and greenhouse gas dynamics of inland wetlands

Giuditta’s PhD thesis involved: 1) improving inland wetlands activity efficiency by properly optimizing carbon sequestration as well as reducing to minimum the greenhouse gases release, 2) identifying key microbial communities and genes that are highly considered to be involved in carbon metabolism, 3) providing new standards and major advantages to scientific community through the constant monitoring of carbon fluxes field from the Australian floodplain freshwater wetlands.

Selected publications

Bonetti, G., Trevathan-Tackett, S.M., Carnell, P.E., Treby, S. and Macreadie, P.I., 2021. Local vegetation and hydroperiod influence spatial and temporal patterns of carbon and microbe response to wetland rehabilitation. Applied Soil Ecology, 163, p.103917.

Bonetti, G., Trevathan-Tackett, S.M., Carnell, P.E. and Macreadie, P.I., 2021. The potential of viruses to influence the magnitude of greenhouse gas emissions in an inland wetland. Water Research, p.116875.

Bonetti G, Trevathan-Tackett S, Carnell P, Macreadie PI. 2019. Implication of viral infections for greenhouse gas dynamics in Freshwater Wetlands: Challenges and Perspectives. Frontiers in Microbiology > https://doi.org/10.3389/fmicb.2019.01962.

Thesis

Ashley’s career as a coastal ecologist has focused on understanding anthropogenic impacts to coastal communities in oyster reefs, seagrass, saltmarsh and mangroves. Her thesis developed fundamental knowledge of how coastal catchments should be managed to protect and conserve important coastal vegetated habitats under future climate change.

Selected publications

Whitt, A.A., Coleman, R., Lovelock, C.E., Gillies, C., Ierodiaconou, D., Liyanapathirana, M. and Macreadie, P.I., 2020. March of the mangroves: Drivers of encroachment into southern temperate saltmarsh. Estuarine, Coastal and Shelf Science, p.106776.

Waryszak, P., Gavoille, A., Whitt, A.A., Kelvin, J. and Macreadie, P.I., 2021. Combining gray and green infrastructure to improve coastal resilience: lessons learnt from hybrid flood defenses. Coastal Engineering Journal, pp.1-16.

Macreadie PI, Ewers Lewis C, Whitt A, Ollivier Q, Trevathan-Tackett S, Carnell P, Thomson A, Serrano O (2017) Comment on ‘Geoenginneering with seagrasses: is credit due where credit is given? Environmental Research Letters 13(2)

Thesis

Reducing emission from degraded wetlands

Katy’s thesis involved modeling carbon sources and sinks from freshwater wetland ecosystems of Southeastern Australia. The aim of this project is to identify long-term carbon storage by analyzing carbon sequestration rates of various inland wetland ecosystems. This connection must be studied to gather knowledge of its significance, and to provide information for better wetland ecosystem management practices.

Selected publications

Limpert, K.E., Carnell, P.E. and Macreadie, P.I., 2021. Managing agricultural grazing to enhance the carbon sequestration capacity of freshwater wetlands. Wetlands Ecol Manage.

Limpert KE, Carnell PE, Trevathan-Tackett SM, Macreadie PI.2020. Reducing emissions from degraded floodplain wetlands. Frontiers in Environmental Science.

Thesis

Value of Australian coastal ecosystems for fish and fisheries

Holger’s PhD research valued Australia’s coastal ecosystems in relation to fish production using ecological, social, and economic measures. He systematically gathered and synthesized existing fisheries datasets to summarise interactions between fish and coastal ecosystems. Results were combined with socio-economic analysis to advocate for ecosystem-based decision making.

Selected publications

Jänes, H., Macreadie, P.I., Zu Ermgassen, P.S., Gair, J.R., Treby, S., Reeves, S., Nicholson, E., Ierodiaconou, D. and Carnell, P., 2020. Quantifying fisheries enhancement from coastal vegetated ecosystems. Ecosystem Services, 43, p.101105.
Jänes H, Macreadie PI, Nicholson E, Ierodioconou D, Reeves S, Taylor M, Carnell PE. 2019. Stable isotopes infer the value of Australia’s coastal vegetated ecosystems from fisheries. Fish and Fisheries. https://doi.org/10.1111/faf.12416

Thesis

Blue Carbon Offset Opportunities within the Corangamite Catchment

Quinn investigated opportunities for carbon offsetting within blue carbon ecosystems of the Corangamite Catchment region in Victoria. He quantified blue carbon stocks and fluxe,s and identified possible mechanisms for the future management of these ecosystems that will aid in the mitigation of carbon re-mineralisation (CO2 released to the atmosphere) and climate change.

Selected publications

Ollivier QR, Maher DT, Pitfield C, Macreadie PI (2018) Punching above their weight: Large release of greenhouse gases from small agricultural dams. Global Change Biology. DOI: 10.1111/gcb.14477

Ollivier QR, Maher DT, Pitfield C, Macreadie PI. 2019. Winter emissions of CO2, CH4 and N2O from temperate agricultural dams: fluxes, sources and processes. Ecosphere. https://doi.org/10.1002/ecs2.2914

Thesis

Distribution, drivers and disturbance of “blue carbon” in southeast Australia.

Carolyn’s thesis focused on understanding the dynamics of carbon sequestration in saltmarshes, mangroves, and seagrasses in Australia.  Her research involved undergoing a comprehensive, large-scale sampling campaign of 96 blue carbon ecosystems across a data-deficient region of southeast Australia, applying these data to create predictive models and produce high-resolution carbon stock maps, and using paleoanalytical techniques and laboratory simulations to measure the impacts of ‘reclamation’ and erosion on blue carbon stocks, respectively.

Selected publications

Ewers Lewis, C. J., Young, M. A., Ierodiaconou, D., Baldock, J. A., Hawke, B., Sanderman, J., Carnell, P. E., and Macreadie, P. I. 2020 Drivers and modelling of blue carbon stock variability in sediments of southeastern Australia. Biogeosciences, 17, 2041–2059

Ewers C, Carnell P, Sanderman J, Baldock J, Macreadie P (2017) Variability and vulnerability of coastal ‘blue carbon’ stocks: A case study from southeast Australia. Ecosystems 21: 263-279

Ewers Lewis C, Baldock J, Hawke B, Gadd P, Zawazki A, Heijnis H, Jacobsen G, Rogers K, Macreadie P (2019) Impacts of land reclamation on tidal marsh ‘Blue Carbon’ stocks. Science of the Total Environment 672:427-437