One Tree Island Fieldwork Trip

In November of 2017, members of Barefoot Biogeochemistry travelled to One Tree Island to investigate its coral reef metabolism and island groundwater effluent.

Pictured left to right: James Archibald, Brendan Kelaher, Tom Glaze, Emily Shaw, Dirk Erler, Ashly McMahon, Kay Davis, and Isaac Santos.

 

Researchers from three teams within Southern Cross University Lismore and National Marine Science Centre enjoying a sunset. Pictured left to right: James Archibald, Brendan Kelaher, Tom Glaze, Emily Shaw, Dirk Erler, Ashly McMahon, Kay Davis, and Isaac Santos.

Kay Davis recording benthic transects

The metabolism study investigated ecosystem calcification/dissolution and photosynthesis/respiration by measuring variations in reef water chemistry during low-tide periods when the lagoon is isolated from the oceanic zone. We can quantify our target parameters by analysing the water for changes in total alkalinity, pH, dissolved oxygen, and dissolved inorganic carbon. Comparing our results to previous studies will determine whether this island’s reef has changed its metabolic activity in the last 50 years, allowing us to understand how  global and local stressors may have  impacted the corals at One Tree Island. 

We also quantified porewater exchange in the island’s lagoon using the radioactive isotope radon to investigate the influence of groundwater on local carbon, nutrient, phytoplankton, and CDOM dynamics.  We had long days, strange hours, equipment malfunctions, health issues, and a shortage of food, but we also had a lot of fun!

Aerial view of time series station and Barefoot Biogeochemistry researchers to investigate groundwater effluent to lagoon. Left to right: a dancing Isaac Santos and laughing onlookers Kay Davis, James Archibald, Ashly McMahon.

ARC success - Douglas Tait, Damien Maher, Christian Sanders and Scott Johnston

The ARC has recognised early career researcher Dr Douglas Tait with a Discovery Early Career Researcher Award (DECRA) worth $392,650 for the project, ‘Is groundwater the missing nutrient source to the Great Barrier Reef?’ (DE180100535).

With the source of only 30% of the nutrient necessary to sustain life on the Great Barrier Reef the study aims to close this considerable knowledge gap.

Despite billions of dollars being spent on improving water quality in the Great Barrier Reef, nutrient budgets and the sources of pollution remain poorly quantified and instances of harmful algal blooms continue to rise. This project will focus on the discharge of groundwater to coastal waters which has been shown elsewhere to be a major component of coastal nutrient budgets.

Nutrients and pollutants can be stored in underground aquifers for decades before flowing to coastal waters. The project will use a combination of cutting edge technology and modelling to quantify how the legacy of past land use practices affects reef nutrient dynamics. It will provide land and marine managers with crucial information to safeguard this precious resource into the future.

For more information or how you can be involved contact Douglas Tait -douglas.tait@scu.edu.au

Chasing methane

By LUKE JEFFREY

Luke Jeffrey collecting methane ebullition samples.

 

Background: Wetlands are hotspots for biodiversity and are highly efficient at capturing carbon dioxide (greenhouse gas) from the atmosphere. Due to their waterlogging nature, these valuable ecosystems can efficiently bury and store this ‘captured carbon’ within their sediments and are generally considered net carbon sinks. Wetlands however, are also one of the largest natural sources of methane (a more potent greenhouse gas), therefore understanding the drivers and pathways for methane emissions are important for land use management and in relation to climate change.

Cattai wetland

Early morning bliss

 

In early September, the barefoot team returned a third time to Cattai Wetland, to capture ‘drying conditions’ as part of a seasonal PhD dataset and ARC linkage project. The fieldwork team consisted of Dr Douglas Tait, Prof. Scott Johnson, Roz Hagan, volunteer and upcoming IP student; Kylie Macguire and PhD candidate Luke Jeffrey.

Our green house gas research station (also a bird hide)

Camp Cattai

 

This study will look at changes in seasonal freshwater wetland hydrology and vegetation ecotypes, and how these relate to methane emissions to the atmosphere. This will be coupled with a companion study looking at carbon burial rates, to overall assess the carbon sink/ source behaviour of adjacent remediated wetland sites (Cattai Wetland, NSW).

Dark chamber fluxes from freshwater lake

 

To account for diurnal variability of methane and carbon dioxide emissions, the recent fieldwork involved 24 hour continuous sampling of simultaneous vegetation ecotypes (at three ‘periodically inundated’ vegetated areas) as well as the drivers such as soil moisture, soil redox, temperature and sunlight.

Phragmites vegetation flux chamber

Measuring soil redox conditions with geoscience team

 

At the same time we also measured diurnal aquatic carbon dioxide and methane emissions from the adjacent lake (a ‘permanently inundated’ freshwater wetland site) and accounted for both diffusive emissions (water to air), vegetation (lilies) and ebullition (methane bubble).

Methane ebullition bubble catchers ready for deployment

Luke Jeffrey collecting methane ebullition samples

Picarro set up at site A amongst the casuarina forest

three simultaneous piccaro time series stations

Kylie recording the ebullition concentration and isotopes at the fieldlab

Compared to the previous flooded and mosquito plagued conditions of April 17, we encountered rather pleasant 4 degree nights and 30+ degree days, with a small dose of rain and gale force winds during the pack down, as nature reminded us who was boss! A massive thank you to all fieldworkers (Scott, Roz, Doug and Kylie) and lab and equipment preparation involved (Ceylena and Paul), and also Bob from Mid Coast Council for logistics and Matt Damon (aka ‘The Martian’) for inspiration, as the trip, sampling, camp fire songs and return to Earth went as smoothly and as efficiently as possible.

Juncus vegetation flux chamber and picarro timeseries station

Is it sweet for the reef?

By Dr Douglas Tait

A small team of Barefoot Biogeochem’ers recently toured the lower Burdekin riverine area surrounding Ayr in North Queensland, sampling groundwater under cane fields. Collecting samples to analyse for nutrient, metal and pesticide concentrations as well as sampling for tritium, radon and radium to determine the age and movement of the water.

Understanding the impacts of this highly modified and managed landscape on groundwater will be important for predicting effects on the nearby Great Barrier Reef. Early results point to improvements in modern farming methods with lower nutrient concentrations in groundwater close to the surface but historical high use of nitrogen fertilizers is clearly detectable in deeper wells.    

Well maintained wells, friendly farmers and a relaxed community atmosphere made the week of sampling in Australia’s sugar capital a smooth and enjoyable experience. The research will be part of an honours project looking at the age and chemical load of the groundwater in the lower Burdekin region as well as ongoing further research into groundwater movement into the reef via shallow and deep submarine ground water discharge and paleo channels.

China visit opens up new collaborations

Barefoot scientist Dr Damien Maher recently travelled to China to meet with scientists working on mangrove rehabilitation and carbon sequestration projects. Dr Maher visited the mangroves in Gaoqiao, Zhanjiang and Guangdong, where scientists from Tsinghua University have established field sites with eddy covariance towers to measure carbon dioxide fluxes between the atmosphere and the mangroves. A new collaboration between the barefoot group and Tsinghua University (China’s number 2 ranked university) has been established. The extensive aquatic expertise of the barefoot team perfectly complements the outstanding micrometeorological work being undertaken by the Tsinghua group. The aim of the collaboration is to close the mangrove carbon cycle by assessing the coupling and exchanges between the atmosphere, terrestrial and aquatic components of mangrove ecosystems.

The coastal squeeze is a global problem for mangroves, with artificial structures such as this walkway preventing landward migration with rising sea level

All aboard … our research vessel for one of our mangrove tours

Blue caebon (carbon) signage at one of the research stations.

Eddy covariance tower measuring carbon dioxide fluxes between the atmosphere and the mangroves.

At the top of the eddy covariance tower

A distinct demarcation between mangroves and aquaculture ponds.

Sleeping in waders: working in inundated wetlands.

By Luke Jeffrey

Last week barefoot team members Dr. Douglas Tait and Luke Jeffrey spent a week wearing waders at Cattai Wetland, NSW. They were accompanied in the field by Prof. Scott Johnson and Roz Hagan (SCU Geoscience), along with honours student Zach Ford.

Luke Jeffrey about to almost complete the 4 days in waders challenge

The research trip was the first deployment of a seasonal sampling strategy, hoping to initially capture some inundated conditions within the freshwater wetland.

Beautiful Cattai wetland

By chance the fieldwork was conducted just three days after devastating flooding and extremely high rainfall events that occurred on the NE NSW coast c/- ex-tropical cycle Debbie. Needless to say the study site was very soggy, very muddy, completely inundated and swarming with some of the worst mosquitoes on record (McDonnell, 2017), thus making the fieldwork challenging!

The muddy campsite set amongst higher ground.

The sampling strategy aimed to measure and compare seasonal methane ebullition, plant mediated methane and diffusive methane fluxes, between different vegetation habitats, and between permanently and non-permanently inundated wetland environments.

Accounting for sediment and diffusive flux using a sediment chamber.

Honours student Zach Ford measuring diffusing flux rates from Cattai wetland.

Custom built vegetation chambers were deployed as a simultaneous time-series experiment to measure the diurnal flux rates of methane from within 3 different vegetation types. To determine some potential drivers and to complete an integrated methane flux of the system, soil redox conditions were measured (with the help of SCU Geoscience), photosynthetically active radiation (PAR), sediment and diffusive flux rates, as well as ebullition (from the permanently inundated site), were accounted for over a complete 24h cycle.

Time series station A and B with gas tubing amongst the krausii rush two feet underwater.

Time series vegetation chamber A and the associated flux of methane and CO2.

Dr Douglas Tait running some ebullition samples on a picarro

Time series B chamber set amongst the tall phragmites.

Time series station C set amongst the casuarina forest.

The research will form a chapter of Luke Jeffrey’s PhD looking at groundwater and carbon dynamics of modified wetlands, under the supervision of Dr. Douglas Tait, Dr. Damien Maher and Prof. Isaac Santos. The research will also provide data for an ARC linkage project looking into ways of maximising carbon sequestration within freshwater wetlands. 

Some tools of the trade.

Australian Mangrove and Saltmarsh Network Conference

The Australian Mangrove and Saltmarsh Network Conference in Hobart was recently attended by Barefoot Biogeochemistry researchers Damien Maher and James Sippo. The catastrophic mangrove dieback in the Gulf of Carpentaria was one of the central themes of the meeting. The ‘Barefoot’ researchers have been focusing on the changes to the coastal carbon cycle following the large scale mangrove dieback which occurred in December 2015. It was a great opportunity to meet with collaborating researchers from all across Australia to discuss the topic.

The poster session with Judith Rosentreter and James Sippo. (Photo: Judith Rosentreter).

 

The team visited the Tasmanian saltmarshes

 

The scenic Tasmanian coastline

2nd NIES International Forum on

Sustainable Future in Asia

Author: Paul Macklin, PhD Researcher in Bali.

Recently I represented NMSC and SCU at the 2nd NIES International Forum on Sustainable Future in Asia at Udayana University in Bali discussing part of my PhD research on carbon dioxide fluxes in natural and artificial tropical lakes and the ramifications of predicted increases in reservoir construction in tropical regions. Other topics included carbon monitoring, waste management and recycling, biodiversity and environmental risk and health in Southeast Asia. There was a strong focus on exploring ways to link science and policy through discussions and networking while promoting investment at local, national and regional levels.   

 "Photo courtesy of Seiji Narita, official photographer of NIES."

It was also reassuring to see the level of scientific and financial commitment directed towards environmental remediation and monitoring and I was particularly impressed with recent advances in environmental satellite technology by the Japanese Aerospace Exploration Agency (JAXA) particularly with the planned launch of GOSAT 2 (http://global.jaxa.jp/projects/sat/gosat2/). I would like to see future collaborations with JAXA involving comparative in situ carbon dioxide and methane studies comparing our recent methodologies with the high-performance on-board observation sensors of GOSAT 2.

Also I had the chance to explore ways to make my current research here in Bali both easier and more effective while discussing the limitations and alternatives to reservoir construction with stakeholders and other potential collaborators. I made many friends, and developed professional relationships while enjoying some great food!

Dr I Gusti Ngurah Suryaputra, my collaborator from Ganesha University, Singaraja, and myself (photo: Agung Sumastra).

 

*This forum was organized by National Institute of Environmental Studies in collaboration with The University of Tokyo Integrated Research System for Sustainability Science, Udayana University and Bogor Agricultural University in Indonesia, and Asian Institute of Technology in Thailand. My attendance was made possible with conference funding from the Southern Cross University Graduate School. A special thanks to Helen Wolton and Gina Smith Lawson from the Graduate School in Lismore and also to my supervisors Prof Isaac Santos and Dr Damien Maher for their constant support. For more details on the conference see http://ifsfa2017.co.id/

 

The Japan Aerospace Exploration Agency (JAXA) displaying environmental monitoring data (photo: Paul Macklin).

 

Me flexing with (R-L) Dr Remi Chandra, Dr Takuya Saito and Dr Hibiki Noda (photo: Shiho Sato).

ASLO Aquatic Sciences Meeting

A barefoot crew just returned from the ASLO Aquatic Sciences Meeting in Hawaii. Lots of fun, good food, meeting old and new friends, and work during free time. Damien Maher and Isaac Santos chaired sessions on carbon cycling and submarine groundwater discharge. The following presentations were given.

Ashley with poster

Ben with poster

James with poster

In search of SGD in Japan

Barefoot Biogeochemists Isaac Santos and Douglas Tait got out of their comfort zone in Japan. They had to wear slippers in the lab and boots in the field to undertake a study on submarine groundwater discharge and carbon inputs into freezing Obama Bay.  

The research relied on collaboration with Japanese colleagues Dr. Ryo Sugimoto from Fukui Prefectural University and Prof. Makoto Taniguchi from the Research Institute of Humanity and Nature (RIHN), and was part of a visiting research fellowship at RIHN.

The project received outstanding support from Japanese students Shohei Takemoto, Hiroyuki Nishimura and Toshimi Nakajima as well as several colleagues from Kyoto. The highest snowfall in the district in over 40 years added a new challenge to groundwater sampling as well as having to use the research boat as an “ice breaker” to get through surface ice on the bay.

Obama Bay is well known for its abundant fisheries resources that are thought to be ultimately fed by groundwater inputs of nutrients.

Dr Isaac Santos and friends