Schlagwort: coral

  • Explore the depths with the PiCam Marine

    Explore the depths with the PiCam Marine

    Reading Time: 3 minutes

    This article from The MagPi issue 74 highlights the use of the Raspberry Pi Zero to build a marine camera for coral exploration. Get your copy of The MagPi in stores now, or download it as a free PDF here.

    Raspberry Pi Picam Marine

    The crew took 20 000 photos in total during the cruise.

    Ecologists in Germany are deploying camera-equipped Pi Zero Ws off the coast of Norway to discover more about coral activity. Dr Autun Purser works in the Deep Sea Ecology and Technology group of the Alfred Wegener Institute. The group has a keen interest in cold-water corals, which are found in most European seas.

    Raspberry Pi Picam Marine

    Besides coral, they identified dozens of crabs.

    “In the last three decades, we’ve started to understand these can form reefs whenever conditions are suitable for growth,” explains Autun. “During our cruise in the Skagerrak, we intended to map corals and see when, and under what conditions, they did most feeding.”

    Feeding time

    Their aim was to continue the development of “cheap camera systems which can be used for a range of applications in the deep sea, down to depths of at least 6000 metres. We investigated the use of Pi Zero W computers and [Raspberry Pi Camera Modules] to record video snippets of both the seafloor and any scientific devices that we place underwater, and we found the small size of the computers to be of great benefit to us.”

    Raspberry Pi Picam Marine

    The PiCam Marines are sent underwater in the deployment basket of a submarine. The captain, crew, and scientists aboard RV Poseidon cruise POS526 were also essential for the initial deployments.

    The Pi Zero Ws and cameras are placed in strong, waterproof pressure containers, and powered by Li-ion batteries that can withstand the cold deep ocean conditions. “The WiFi connectivity allowed us to set up a router on deck to both initiate our cameras and, on retrieval from the sea-floor, download our collected images without having to reopen the pressure housings,” reveals Autun.

    He and two colleagues programmed the camera system using Python 3 to turn on an LED light and take a maximum resolution image, at set times. It has proven “capable of imaging individual corals from 2 m distance, allowing us to tell if the tentacles were actively extended or not.”

    Website: LINK

  • Protecting coral reefs with Nemo-Pi, the underwater monitor

    Protecting coral reefs with Nemo-Pi, the underwater monitor

    Reading Time: 3 minutes

    The German charity Save Nemo works to protect coral reefs, and they are developing Nemo-Pi, an underwater “weather station” that monitors ocean conditions. Right now, you can vote for Save Nemo in the Google.org Impact Challenge.

    Nemo-Pi — Save Nemo

    Save Nemo

    The organisation says there are two major threats to coral reefs: divers, and climate change. To make diving saver for reefs, Save Nemo installs buoy anchor points where diving tour boats can anchor without damaging corals in the process.

    In addition, they provide dos and don’ts for how to behave on a reef dive.

    The Nemo-Pi

    To monitor the effects of climate change, and to help divers decide whether conditions are right at a reef while they’re still on shore, Save Nemo is also in the process of perfecting Nemo-Pi.

    Nemo-Pi schematic — Nemo-Pi — Save Nemo

    This Raspberry Pi-powered device is made up of a buoy, a solar panel, a GPS device, a Pi, and an array of sensors. Nemo-Pi measures water conditions such as current, visibility, temperature, carbon dioxide and nitrogen oxide concentrations, and pH. It also uploads its readings live to a public webserver.

    The Save Nemo team is currently doing long-term tests of Nemo-Pi off the coast of Thailand and Indonesia. They are also working on improving the device’s power consumption and durability, and testing prototypes with the Raspberry Pi Zero W.

    web dashboard — Nemo-Pi — Save Nemo

    The web dashboard showing live Nemo-Pi data

    Long-term goals

    Save Nemo aims to install a network of Nemo-Pis at shallow reefs (up to 60 metres deep) in South East Asia. Then diving tour companies can check the live data online and decide day-to-day whether tours are feasible. This will lower the impact of humans on reefs and help the local flora and fauna survive.

    Coral reefs with fishes

    A healthy coral reef

    Nemo-Pi data may also be useful for groups lobbying for reef conservation, and for scientists and activists who want to shine a spotlight on the awful effects of climate change on sea life, such as coral bleaching caused by rising water temperatures.

    Bleached coral

    A bleached coral reef

    Vote now for Save Nemo

    If you want to help Save Nemo in their mission today, vote for them to win the Google.org Impact Challenge:

    1. Head to the voting web page
    2. Click “Abstimmen” in the footer of the page to vote
    3. Click “JA” in the footer to confirm

    Voting is open until 6 June. You can also follow Save Nemo on Facebook or Twitter. We think this organisation is doing valuable work, and that their projects could be expanded to reefs across the globe. It’s fantastic to see the Raspberry Pi being used to help protect ocean life.

    Website: LINK