Biology subjects

Lopez-Victoria, M.

Publications and source records attributed to Lopez-Victoria, M..

3 recordsLinked to original sources

bioRxiv2024

Accelerated growth of the scleractinian coral Orbicella faveolata under turbid and polluted water conditions

Cartagena Bay, Colombia, experienced historical changes in water quality, mainly due to dredging and channelization of the Canal del Dique, which connects the bay with the Magdalena River. In 1981 the largest dredging events occurred in the Canal del Dique, which negatively affected the water quality in the bay. In this bay, the coral reef of Varadero depicts high coral diversity and large coral colonies, showing apparent signs of a healthy ecosystem, under highly turbid and polluted waters. Here, we evaluated the potential effects of historical water quality changes and environmental variables on the coral skeletal growth of Orbicella faveolata. We obtained coral growth information from 65 years in the period 1951-2015. Coral skeletal density was 0.73 g cm-3, linear extension 1.02 cm yr-1, and calcification 0.74 g cm-2 yr-1. After 1981, significant changes in coral growth and luminescence were found: skeletal density decreased (9.9%), linear extension increased (6.6%), and skeletal luminescence was less intense (1.6%). In overall, Atlantic Multidecadal Oscillation (AMO) data explained changes in skeletal density (8-10%) and linear extension (7-19%). Air temperature explained changes in skeletal luminescence (22-45%). Water flow of the Canal del Dique did not contribute significantly to any coral growth and luminescence variables. The growth of O. faveolata in Varadero Reef was characterized by low density skeletons and an accelerated linear extension, apparently influenced by the dredging events of 1981. Further research is required to understand coral growth responses and resilience to the conditions of high turbidity, pollution, and low light in Cartagena Bay.

ecology↗

bioRxiv2024

A paleogenomic approach to reconstruct historical responses of coral reefs to anthropogenic change

Coral reefs are declining worldwide due to anthropogenic environmental change. The foundation and health of these ecosystems rely on the harmonious functioning of all members of coral holobionts, i.e., cnidarian host, symbiotic microalgae, and associated microbiome. Coral stress responses often involve shifts in the taxonomic identity of their symbionts and microbiomes. Tracing back changes in coral holobiont composition over prolonged time periods can help us reconstruct health history of reefs and gain a better understanding of coral response to current stressors. Here, we focused on a major Caribbean reef-builder coral, Orbicella faveolata, from Varadero Reef, Colombia. This reef has undergone extensive freshwater sediment discharge and pollution for decades as result of urbanization. We show, for the first time, that paleogenomic and paleoclimatic approaches can be combined to reconstruct historical coral holobiont dynamics potentially associated with anthropogenic disturbances.

molecular biology↗

bioRxiv2021

Physiological and ecological consequences of the water optical properties degradation on reef corals

Degradation of water optical properties due to anthropogenic disturbances is a common phenomenon in coastal waters globally. Although this condition is associated with multiple drivers that affect corals health in multiple ways, its effect on light availability and photosynthetic energy acquisition has been largely neglected. Here, we describe how declining the water optical quality in a coastal reef exposed to a turbid plume of water originating from a man-made channel compromise the functionality of the keystone coral species Orbicella faveolata. We found highly variable water optical conditions with significant effects on the light quantity and quality available for corals. Reduction of light penetration into the water column elicits the development of low-light phenotypes close to theoretical limits of photoacclimation despite their occurrence at shallow depths. Predicted photosynthetic energy depletion with increasing depth is associated with patterns of colony mortality and contraction of the habitable space for the population. A numerical model illustrates the potential effect the progressive degradation of water optical properties on the gradual mortality and population decline of O. faveolata. Our findings suggest that preserving the water optical properties seeking to maximize light penetration into the water column may have an extraordinary impact on coral reefs conservation, mostly toward the deeper portions of reefs.

physiology↗