During the CBR5 campaign (in February), the team, with the precious help from Suttakkua diving, has deployed some instruments to collect data on the temperatures, light exposure and currents on the Coralligenous area in Marzamemi.
The Suttakkua boat, ready to set sailProf. Basso (right) and prof. Rosso (left), inspecting the currentometer before leaving the pier
The currentometer has been set on the sea floor (using some heavy ballast), where he will measure the direction and strenght of the currents. Then, other instruments will measure the water temperature and sunlight changing throughout the many months that they will be underwater.
The currentometer and its ballast before deployment (the ballast is neutral towards the environment avoiding polluting the seafloor)Nunzio Pietralito of the Suttakkua diving ready to deploy the currentometer at sea. An unexpected gift… Coralligenous algae have grown over a plastic bottle on the seafloor. Studying the rate of growth on various surfaces is a very effective methods of learning how these algae live.
During the CBR4 campaign the staff from the University of Catania (with the help of Suttakkua diving) has recovered a sediment core off the Marzamemi coast. The analysis of the sediments of this area could give us extremely important information on the Coralligenous colonization and growth.
The corer before deploymentRiccardo Leonardi (University of Catania) deploying the corer on site. portion of one of the recovered core, you can see the coarse sediments with sand, maerls and dead Posidonia leaves
A fundamental step of the research is understanding what species contribute to the formation of the bioconstructions. We are consolidating previous knowledges about the role of the different taxa, which are the constructors, the bafflers, the binders, the dwellers and the destroyers, but we are also having knew interesting discoveries!
Densely colonized block of coralligenous.
At the University of Catania we are focusing on serpulids, bryozoans, foraminifers and ostracods, finding a lot of species, of which some were unexpected!
Prof. Sanfilippo (left) and prof. Rosso (right) (University of Catania) observe the samples under the stereomicroscope.Example of a sample obtained from scratching.Serpulid (Serpula vermicularis) covered with an encrusting bryozoan.Coralligenous surface with interaction between different encrusting organisms (bryozoan, which forms the greater cover and pink arborescent foraminifera), perforating sponge (purple points).Tubes of serpulids (Semivermilia crenata) covering a bryozoan (Onychocella marioni).
For our second analysis we had to go a little deeper and cut the build ups entirely.
To cut such a big chunk of rock is no small feat and it did require impressive gear to accomplish.
Luckily, we had the help of Mario Airoldi company. The extremely skilled workers there were able to cut the build-ups without effort with the help of a giant circular saw, usually employed to cut big rock pieces.
The build up is placed in position after the saw is mounted on its arm
Thanks to the flawless cut we were able to recover all the material in beautiful cuts, that are ready to unveil all their knowledge to us.
For our second analysis we had to go a little deeper and cut the build ups entirely.
The cut sequence of the build-up. A huge amount of water for the cut. The saw is extremely precise and cut the carbonate build-ups effortlessly.
Let’s start the new year with some good news and awesome pictures!
We are now analyzing the amazing coralligenous samples collected during the CBR2 campaign.
In order to study the build-ups, we have to look at them, not only from the outside, but also from the inside.
To do so, we have employed a double approach: firstly, a non-invasive analysis and secondly an invasive one.
The first analysis is a C-T Scan of the build-ups, utilizing the C-T machine at the San Gerardo Hospital in Monza, usually utilized for patients. We thank Dr. De Ponti and her staff for their help.
The CT machine is about to receive a very “peculiar” patient.
The analysis produced a series of pictures that show the inside of the coralligenous build-ups.
The coralligenous build-ups x-ray images. The various gradation of grey indicate differences in material density. It is also possible to see bivalves remains inside the build-up (red arrow)
While collecting samples and analyzing the seafloor, we are also developing and testing the corer that will eventually be used on the project’s ROV to drill the coralligenous in its native environment. This work is carried on by the researchers at the University of Calabria.
Panoramic view of a blok of the calcareous tufa
Comparison between a coralligenous sample (left) and a calcareous tufa sample (right). Note the similar framework of the two samples despite the different origin of the materials.
To avoid testing the drill on the precious coralligenous samples, the drilling test is performed on calcareous tufa (selected for its geomechanical similarity with the coralligenous). The area selected for the collection of the samples is «Pietra Gna’zzita» near the Longobucco village (Calabria, Italy).
The prototype consists in a brushless gearmotor (with two speed ratio) manufactured by 3D printing technologies (plastic and metal) mounted on a linear slider fixed on a stainless-steel frame.
Prototype 3D model
The test bench is designed to simulate drilling in a controlled environment (the water tank), using a 63mm diamond core drill. Several tests allow to evaluate the operating parameters of the coring system (rpm, feed rate, etc.) and the mechanical resistance of samples characterized by large cavities. A wi-fi interface has been used to monitor the motor control unit and record log data.
Corer Unit in water tank, with the 63mm diamond core drill
Sample 1: homogenous calcareous tufa
Sample 1: core D 55 mm x L 300 mm (collected in 2 steps to verify core breaking procedure)
The results allow to measure the optimal operating parameters to identify the requirements of the system and optimize the design process of the mechatronic platform to be installed on the ROV.
Teachers and students of the International Master’s Degree in Marine Sciences collaborate with the Intergovernmental Oceanographic Commission – UNESCO, for the design and public presentation of the Ocean and Climate Village space at PreCOP26 at the Milano Triennale https://all4climate2021.org/.
The PreCOP is the preparatory ministerial meeting that precedes the COP (Conference of the Parties), the United Nations climate summit. This year PreCOP26 will be hosted in Milan and COP26 will be held in Glasgow.
The Ocean and Climate Village is an educational space where children and families can learn about the message and objectives of the Decade of the Sea, with a focus on climate change and the Mediterranean Sea. The village is designed as a cluster of educational activities for different age groups, from the youngest to the adults.
A second phase of the CBR3 campaign. The researchers of the University of Milano-Bicocca (you can see in the picture, Alessandra Savini and Luca Fallati in scuba gear!) are doing the photogrammetry. They are taking a series of continuous pictures of the seafloor at 30 m depth with the high-definition camera.
Once again Suttakkua diving aided the CBR3 campaign.
This dim-light environment fosters the ideal conditions for the coralligenous to thrive, but there are still many unknown to the understanding of this amazing ecosystem. The photogrammetry will create a 3D model that is going to be integrated with the sea bottom profile (acquired during the CBR1 campaign), allowing us to shed more light on the geology and geomorphology of the seafloor.
Follow us on Instagram @cresciblureef #CBR to see other amazing video of the CBR3 campaign.
Here we are, the CBR3 has started and with it the first attempt to photogrammetry on the coralligenous. In the picture you can see Alessandra Savini and Luca Fallati (of the University of Milano-Bicocca) working at ca. 10 m depth, with the indispensable help of the Suttakkua diving.
They are swiping the sea floor testing the high-definition camera. After the test they will go to higher depths searching for the coralligenous and use the camera there. The objective is to integrate the acquired images with the sea bottom profile, thus creating a reliable 3D model for the analyses. We will use this 3D model, with the samples acquired during the CBR2, to better understand the geological and geomorphological conditions under which the coralligenous grows.
Follow us on Instagram @cresciblureef #CBR to see other amazing video of the CBR3 campaign.
After five days of intense work, we can announce: we got it!
Riccardo Leonardi (technician at the University of Catania) and our local collaborators from Suttakkua diving did 5 dives, during which they were able to collect two amazing coralligenous build-ups we identified at 36 m of water depth. They also collected the sediments from surrounding area and small surface samples from other near-by coralligenous structures. In addition, they placed the Concretion Accretion Unit (CAU) which will help us in understanding how and when different organisms are able to encrust. The coralligenous structure are 40 and 56 cm in height. They show a high biodiversity at surface, with fleshy algae, erected bryozoans, mollusks, serpulids and for sure calcareous algae. Below this surface aspect, the structures are both very compact (and heavy) and dominated by calcareous algae, bryozoans and serpulids.
Stay tuned! We cannot wait to start the study of these amazing samples!
