Abstract
The industrial park of Quintero Bay (QB) in the central coast of Chile was established in the 1960s, presents high levels of pollution due to the industrial activity, and it is known as one of the five Chilean “sacrifice zones”. Lessonia spicata is the most important habitat-forming kelp species in the intertidal along the central and south shores of Chile, and currently there are no morphometric and population studies of L. spicata (or other seaweed species) nor studies about the effects of pollution on its development in QB and neighbouring sites. In this context, the aims of this study were (i) to register the abundance and morphological features of L. spicata populations from Ventanas, Horcón and Cachagua (sites with different pollution histories and located only up to 40 km from the QB); ii) to determine the heavy metals (HMs) concentration in seawater and marine sediments; and (iii) to evaluate in vitro the effects of exposure to seawater from the three sampling sites on spore release and early developmental stages, up to the juvenile sporophyte. Results showed that the chronically exposed Ventanas kelp population had the smallest adult individuals in comparison with the other sites. Ventanas and Horcón registered high HMs concentration in the seawater and marine sediments exceeding the international permissible limits (e.g in seawater Cu 20–859 μg L-1; sediments Cu > 50,000 μg kg-1). Unexpectedly in Cachagua, a site often considered unpolluted, high concentrations of Cu and As were also registered in the seawater (859 and 1,484 μg L-1, respectively) and of As in marine sediments (20,895 μg kg-1). Exposure of gametophytes to the seawater from Ventanas resulted in a developmental delay compared to the other treatments; however, low sporophyte production was determined in all treatments. Our results indicate that QB, more notably Ventanas, induce highly negative effects on individual development, and consequently on seaweed populations, which suggest a long-term negative impact on the community structure of these marine zones. Furthermore, the high concentrations of HMs reported here at Cachagua suggest a recent expansion of pollution along the central coast of Chile, evidencing effects on the marine ecosystem health even on sites far from the pollution source.
Highlights
Heavy metals (HMs) are inorganic pollutants naturally present in the environment, which have increased significantly due to anthropogenic action [1]
There are many factors involved in the fitness and development of seaweeds such as L. spicata, especially in terms of pollution impact evaluations
One unexpected result of this work is that the HMs concentration of Cu and As in seawater and sediment samples was above the international normative in all three sampling sites
Summary
Heavy metals (HMs) are inorganic pollutants naturally present in the environment, which have increased significantly due to anthropogenic action [1]. These metals generate alterations in the normal metabolism, development, and fitness of animals, plants and seaweeds, depending on their concentration, distribution and speciation [2,3,4]. Species of the genus Undaria and Lessonia, are sensitive to high concentrations of HMs, principally Cu, which trigger oxidative stress, cell damage and negative effects on spore release, germination and gametophyte development [4, 16,17,18,19,20]. Contreras-Porcia et al 2020 [17] demonstrated that binary and tertiary mixtures of Cu, Cd, and polycyclic aromatic hydrocarbons (PAHs) have negative synergistic effects on spore settlement of the kelps Lessonia spicata and M. pyrifera
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
