After a few quiet months without input from Early Career Researchers, it’s great to welcome Danielle Marchant to the WTT blog. Danielle obtained her degree in Biological Sciences at Bournemouth University where she was interested in multiple stressors and their effects on ecological processes. Her research project focused on the effects of warming on two different types of algae, the toxic Microcystis aeruginosa and green alga Chlorella vulgaris. From there, she went on to the Freshwater & Marine Ecology MSc at QMUL, studying the effects of warming on N2 cycling by algal biomass in a mesocosm experiment that has been running for 15 years. Danielle crossed paths with WTT’s Prof in Practice, Jonny Grey, during a residential field course in the Lake District which Jonny helps organise. Over to Danielle:-
Here I am, a year to the day that I officially started my PhD. It is safe to say that the journey so far hasn’t been all fun and games, and it seems like everything that could go wrong did go wrong! I am still here though, and still loving every second of my research experience. My PhD is part of the EU INTERREG France (Channel) England project “Preventing Plastic Pollution” co-financed by the European Regional Development Fund. We are seeking to better understand and reduce the implications of plastic pollution in aquatic environments. Previous research has focused on the implications of larger macroplastics, such as fishing nets, plastic bottles and bags, on marine mammals, because the entanglement and ingestion of this larger marine debris is more obvious and apparent than the influence of smaller micro particles. However, these micro particles are highly abundant in all aquatic ecosystems and have been found to have detrimental effects on aquatic organisms. I will focus on the effects of microplastics on freshwater communities and ecosystems.
During my first year, due to the coronavirus pandemic, I spent a lot of time working on a meta-analysis. I looked at the effects of microplastics on chemical toxicity to aquatic organisms, one of the most widely debated subjects in microplastic research. After spending the first few months working at home on my computer, it was so nice to be able to get out and set up our mesocosm facility at the River Laboratory, Dorset.
Several PhD students, including myself, will look at the implications of microplastics, bio-based bioplastics and their interactive effect with eutrophication (nutrient enrichment) on various aspects of freshwater communities and ecosystem functioning. I will largely focus on community structure, the cycling of carbon and nitrogen, as well as the interactions between phytoplankton and zooplankton in terms of resource use and uptake. Scaling up from laboratory experiments to these mechanistic experiments feels very daunting, but also super exciting.
So far, the meta-analysis, setting up and planning of the mesocosms went relatively well. The lab work, not so much. It took a lot of time to figure out the culturing of the freshwater zooplankton species, Daphnia magna. The population would collapse almost every other week and I couldn’t find an explanation as to why! It took a fair few months to get healthy cultures, but now I am finally working on my first dose-response laboratory experiments. I hope to use a variety of functional groups in the future, to determine the effects of microplastics on a variety of freshwater organisms. I am looking at a range of environmental concentrations, and a range of higher concentrations where it is expected that there will be an observable effect on ecotoxicological responses of freshwater macroinvertebrates (Asellus aquaticus, Gammarus sp.), zooplankton (Calanoid sp.) and phytoplankton (e.g., Chlorella vulgaris). Using these concentrations will help me to disentangle the “true” effects of microplastics in the environment, as compared with many previous studies that used only exceptionally high concentrations of microplastics to produce an observable response.
Hopefully I will have some very cool results to share with you all soon. To follow the journey of the PPP project, you can visit preventingplasticpollution.com and follow us on social media. Facebook: https://www.facebook.com/preventingplasticpollution.eu/ , Instagram: plastic_eu and Twitter: @Plastic_EU.