Researchers from the Repopulation and Culture Department, Aquaculture Research Division of IFOP, study the potential benefits and interactions of co-cultivation of extractive species under the small-scale aquaculture (APE) scheme in the environment and as a development alternative for artisanal fishermen and fish farmers. One study topic focuses on areas affected by high levels of nutrients produced by human activities (eutrophication), where bivalve molluscs could help reduce the load of organic matter and control the abundance of microalgae through filtration, while the macroalgae capture and consume inorganic nutrients. Also, macroalgae can be used as bioremediators of environments affected by heavy metal contamination generated by industrial waste, for example. "This line of research is being addressed as one of the objectives of the study" Comprehensive Program for the Development of Algae Aquaculture for Artisanal Fishermen and Small-scale Aquaculture ", which is part of the Permanent Program on Fisheries and Aquaculture, which is carried out in by virtue of the agreement between the Undersecretariat of Economy and Smaller Companies and the IFOP, the scientific and technical counterpart being the Undersecretariat of Fisheries and Aquaculture, indicated the Head of the Department of Repopulation and Culture, Dr. Francisco Cárcamo.

 

 

Another line of research undertaken by members of the department focuses on mitigating the effects of climate change on small-scale aquaculture. In this context, if bivalves and macroalgae are cultivated together, they could benefit each other since some of their biological processes can be coupled. For example, ocean acidification (reduction of ocean surface pH) is a phenomenon generated by the diffusion of atmospheric CO2 into seawater. This reduction in pH produces an accelerated dissolution of the shells of the bivalves at the same time that it hinders their formation (calcification), which affects the growth of these organisms. Macroalgae, during photosynthesis, use CO2 from seawater, causing an increase in pH, which favors calcification in bivalves. At the same time, macroalgae need nutrients and CO2 to grow, which are excreted into the environment as waste by bivalves. This is the main theme of the project (FONDECYT initiation 11190297) led by Dr. Pablo Leal, whose experiments are being carried out at the Laboratory of Marine Resources and Resources (ARMlab), located at the Hueihue Experimental Center, Ancud.

 

 

Finally, Dr. Luis Henríquez has led the study of the potential positive effects of small-scale aquaculture on local ecosystems, such as the formation of emerging habitats. In general, these emerging habitats are born after the shedding of bivalves and macroalgae that fall to the sea floor. This could increase the abundance and richness of species under cultivation centers compared to contiguous areas without cultivation centers. This is relevant since the species found in these new habitats include species of ecological and economic importance that could eventually be managed and exploited, in addition to providing larvae of said species. However, it should be noted that the positive effect on the local ecosystem is limited to smaller farms and extractive species that do not require artificial feeding, such as bivalves and macroalgae, and under site-specific physical conditions.

 

In summary, an important part of the research carried out by the Department of Repopulation and Culture is aimed at providing scientific-technical bases to support the development and sustainability of small-scale aquaculture in Chile with benefits for the environment and for fishermen and farmers.