A study published in the scientific journal Ecosphere and applied to species from the northern and southern hemispheres observed the influence of “vertical” environmental variants, over other gradients in coastal areas.

To verify the influence of these environmental variations, two dominant marine species in their corresponding environment were also studied. © Alexis Catalán.

Daniela Jofré, IDEAL Center. On temperate rocky shorelines, environmental stress caused by tides produces a large “vertical” variation in the abundance and diversity of marine species. Along the coasts, environmental factors such as wave exposure or productivity generate “horizontal” biological variation that, when measured at wide sampling intervals (up to hundreds of kilometers,) generally exceeds vertical biological variation.

“The question we asked ourselves was how does vertical and horizontal biological variation compare when the latter is measured in environmentally similar habitats, and whether this comparison gave similar results between the coasts of the Northwest Atlantic and the Southeast Pacific,” said Dr. Nelson Valdivia, ecologist at the Center for Dynamic Research of High Latitude Marine Ecosystems (IDEAL) of the Austral University of Chile (UACh) and co-author of the study.

The research led by Alexis Catalán, doctoral student in Marine Biology at the UACh, considered that these types of environments maintain a fairly marked variation at the vertical level, due to the fact that on the surface they present very unfavourable conditions for marine organisms, while descending to the sea and due to the characteristics of this element, currents allow the arrival of nutrients and improve the conditions for marine species.

To verify the influence of these environmental variations, two dominant marine species in their corresponding environment were also studied. The first of these is known as “rock algae” (Ascophyllum nodosum,) commonly found in the northern hemisphere (Europe and the United States.) The second species of study was the maico mussel (Perumytilus purpuratus,) a bivalve geographically distributed from Ecuador to the Strait of Magellan by the Pacific Ocean, bordering the entire coast of our country.

Both species tend to inhabit the intertidal zone in large numbers, so any change in their abundance affects their entire ecosystem. © Alexis Catalán.

Both species tend to inhabit the intertidal zone in large numbers, so any change in their abundance affects their entire ecosystem. In addition, both A. nodosum and P. purpuratus are constantly being influenced by vertical gradient environmental variabilities.

“Although the two communities and species are different and are in different geographic locations, they showed similar patterns of variation,” said Dr. Valdivia, who is also an academic at the Institute of Marine and Limnological Sciences (ICML) of the UACh.

The study establishes that the landscape of the intertidal zone depends significantly on this vertical pattern. “When projects are built in coastal areas that imply, for example, a change in the waves, a strong impact is generated on the present ecosystem, so these variables must be taken into account,” concluded Dr. Valdivia.

The research was published in the scientific journal Ecosphere.