It is estimated that Microalgae produce up to 50% of the oxygen we breathe, making them a valuable resource to all terrestrial species including ourselves. Additionally, as one out of every seven people on Earth depends on seafood for their daily protein requirements, understanding the microalgae at the root of the marine food web is important to a large number of people's survival. In recent years, it has been proposed that shifts in planktonic populations and species diversity correlate to the rise of water temperatures and acceleration of marine climate, pointing to the possibility of a large impact on the entire marine biome. This is why marine scientists worldwide are making these tiny organisms the focus of their research.
The analysis of the ocean surface water communities is at the heart of the marine scientists' work. Traditionally, this process required collecting in-person samples during expensive and time intensive boat expeditions to evaluate later. Jupiter Research Foundation, however, is developing a compound microscope system that travels on an autonomous, unmanned Wave Glider and allows in-situ water sampling, immediately screening for microorganisms or other particles. The microscope then takes date/time/geolocation stamped pictures of anything it finds and sends these pictures back to the lab in near real-time.
Not only is this approach significantly less expensive than the traditional sampling process, providing budget for a larger number of autonomous expeditions, it also provides a greater spatial temporal range of sampling to produce better informed predictions of future microalgae patterns.
Another unique feature of the Autonomous Microscope is its combined use of darkfield microscopy and PS2 Fluorescence to produce both striking and recognizable images. Although the microscope prototype originally utilized brightfield, it was found that darkfield imaging ultimately aids in the distinguishment of phytoplankton and zooplankton and yields optical concentration of samples by allowing multiple exposures per image. Darkfield microscopy illuminate the membranes or edges of an object against a black background by configuring the condenser to pass only the light scattered by the specimen through the lens objective. This is opposed to brightfield microscopy where light is directed by the condensor through the specimen and then continues through the lens objective. The PS2 chlorophyll reaction takes place when a specific wavelength of blue light is focused down on the specimen, stimulating the species' chloroplasts to flouresce in a red wavelength then captured by the microscope's camera. What results are images of starkly outlined organismal membranes enclosing red organelles.
Currently, Jupiter’s microscope team is working to produce solutions to other problems and inquiries that arise when dealing with an autonomous plankton sampler. These include biofouling of the lens, imaging of larger and smaller specimens, and the creation of a photo library to automatically identify recorded organisms.
- In an initial pilot project and proof of concept, a microscope equipped Wave Glider participated in the Fall CANON 2014 experiments.
- Based on that experience and many lessons learned during that event, we improved the robustness and quality/quantity of pictures taken and joined Spring CANON 2015 alongside the Monterey Bay Aquarium Research Institute (MBARI). At the center of this event stood an investigation into the Harmful Algal Blooms (HABs) that occur every spring in the Bay and are triggered by the seasonal upwelling of cold nutrient-rich deep water for which the Northern Californian Coast is known.
- At OCEANS 2016, we presented the microscope system to a broader technical and scientific audience. Please find a .pdf of our technical paper here.
- Then we ground-truthed the system. Collaborating with MBARI and using microbeads as well as lab grown Pseudo-Nitzschia sp. cultures, we were able to verify that size measurements as well as density observations were correlating the properties of the cultures we used. This important finding concluded the development of the brightfield capabilities of our system and we refocused on darkfield.
- Our next mile stone is the launch of the fully verified darkfield, fluorescence microscope system.
For more about this project, please contact us at Autonomous-Microscope@jupiterfoundation.org