Plankton Practice

We are currently in the process of setting up our one-year project funded by India’s Department of Biotechnology (DBT) to promote the use of foldscopes in research (#IndiaFoldscopePhase1). Our proposed project #aims to not only understand diurnal and seasonal #plankton dynamics but also plans to establish predictive relationships between satellite-derived ocean surface metrics and in-situ measurements (#AndamanPlankton).

In order to meet our project objectives we will be filtering 1000s of litres of seawater using fine mesh plankton nets and these filtered samples will be analysed for phytoplankton and zooplankton species richness and diversity as well as chlorophyll content. Given the wide size range of the marine plankton we are interested in (2 – 20000 µm), our #methods will employ both foldscopes and dissection microscopes. The foldscopes will be very valuable for taking high resolution photos and currently we have been practicing creating slides. Shared here are few of the earliest images and videos to come out of this work.

Since some of the zooplankton may be very large (200 – 2000 µm), we realised we needed thicker #slides with deeper wells, so using a plastic sheet (approximately 2000 µm or 2 mm thick) we created our own frame on which to mount drops of filtered sample in-between two pieces of clear tape. While phytoplankton, on the other hand, we fixed in the foldscope provided paper slides. So far our limited slide making experience has often almost always resulted in leakage or pesky air bubbles. Furthermore we find using live samples can be tricky – at times the critters move around way too fast for accurate ID. We are looking to improve slide design as well as try agents (like glycerin) to increase fluid viscosity without killing the organisms to make it easier to ID them. Suggestions are highly welcome! We have a lot of seawater to process and thus rely on streamlining our effort and efficiency!

So far, during our practice sessions with the foldscope, we have #found nematodes and mites in pond freshwater; and copepods, diatoms, planktonic gastropods and polychaete larvae from seawater. Watching all these guys jump and explore right under your smart phone is an exciting experience. Our humid island environment has made the foldscope bend a bit – making it all the more challenging to focus, and thus we have only started work with one DBT provided Foldscope microscope and are saving the rest in climate controlled conditions for later on.

We eagerly await the start of this project and are simultaneously working on securing sampling equipment and government permissions to sample in the seas neighbouring our research base ( #Partnerships with satellite oceanographers, marine biologists and biological oceanographers at INCOIS, Pondicherry University and NIOT are also being sought to achieve programme goals.

#IndiaFoldscopePhase1 – DBT Foldscope Category B Project Details:
Project Title: Integrating microscopy and satellite oceanography to understand the dynamics of planktonic communities around the Andaman Islands
Principal Investigator: Mahima Jaini, Marine Research Officer, Dakshin Foundation
Location: Andaman Nicobar Environment Team, Wandoor, South Andaman, India

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