SANTA CRUZ DE TENERIFE, 27th February (EUROPA PRESS) –
The Research Group on Marine Biology at the University of La Laguna (BOTMAR ULL) has recently released the first scientific article in the journal ‘Frontiers in Marine Science’ detailing the process of colonization of the lava deltas of the Tajogaite volcano.
These novel marine environments represent an excellent natural laboratory for studying ecological processes that are challenging to reproduce in controlled settings, such as the primary succession of an ecosystem following the conclusion of a volcanic eruption.
Observations indicate that fish have been the quickest to populate this new habitat, followed by invertebrates and, at a slower pace, macroalgae.
The publication is authored by Carlos San Gil Hernández, Daniel Álvarez Canali, Javier Reyes, Julián Rodríguez, and Marta Sansón Acedo, who leads the BORMAL ULL group.
During these primary succession processes, all organism communities start from zero as they colonize a completely sterile substrate without any existing life forms. In these initial evolutionary stages, unique demographic events occur, often as a result of minimal competition and species interaction.
Consequently, it is possible to encounter communities and populations of organisms in these habitats that are scarce or absent in more mature ecosystems. This study specifically examined the development of intertidal and subtidal communities at 2, 4, 5, and 7 months post the eruption’s end. The sampling included macroinvertebrates and algae in the intertidal zone, and fish, macroinvertebrates, and algae in the subtidal zone.
To evaluate and confirm the progression of this new ecosystem, the lava delta of the San Juan Volcano (1949) was selected as a control reference area.
ECOSYSTEM’S EVOLUTION
The colonization of the deltas has been swift, with 64% of the species present in the control area already reaching the new lava flows. With the increasing inclusion of species, the complexity of the communities has been progressively rising with all of them following the same trajectory: converging towards communities resembling those established in the control area, albeit at varying rates of change over time for each cluster.
After seven months, fish were the quickest, exhibiting slight differences between the lava deltas and the control area. Following them, invertebrate communities have undergone the most rapid changes, whereas the evolution of macroalgae communities has been slower. Thus, different organism communities are at different succession stages, some more advanced while others are still in primary stages.
Fish have been the earliest arrivals as adults from unaffected surrounding areas ventured to colonize the deltas. Conversely, colonization by invertebrates, mainly via currents carrying larvae or diaspores like algae, has been a slower process.
Another characteristic of primary successions is the significant changes in the specific composition of communities, where certain pioneer species are replaced by other species towards the end of succession. This shift has only been witnessed with algae, while the species dominating the deltas in fish and invertebrates are the same as those prevailing in mature, undisturbed ecosystems.
BOTMAR ULL has been conducting research in the delta region since February 2022, with the most recent periodic monitoring campaign concluded a few weeks ago. Since the eruption’s end, the group has conducted over 150 dives in the area to study the gradual colonization of these habitats.
Nonetheless, their studies extend far beyond this recently published work, encompassing various experiments and samplings to comprehend the settlement patterns and genetic structure of the species establishing themselves there. Additionally, technical dives are carried out to gather data at greater depths where recreational diving limits access.
In recent expeditions, the group has initiated the study of marine communities in areas recording anomalies in the carbon and pH systems. This project is supported and funded by the Ministry of Science, Innovation and Universities, through the Knowledge Generation Projects scheme; the Cabildo of La Palma, in collaboration with the University of La Laguna, ‘Campus Oceano’; and the Canary Islands Ocean Platform which provides logistical support for these investigations under its DELTA project.
