Interest in Baccharis linearis has increased as an alternative for assisted phytostabilization due to its spontaneous colonization of tailings dumps. The search for a novel fast-vegetative propagation technique to accelerate its coverage on mine tailings is a promising research area for sustainable mine closure plans. In this study, we determined the optimal proportion of compost and tailings as growing media to promote fast B. linearis propagation through a compound layering technique. The assessed growing substrates were: 100% tailings, 70% tailings + 30% compost, and 50% tailings + 50% compost. After 84 days of growth, the change in number and height of layering branches, root and shoot dry mass, percentage of ground coverage, and substrate chemical properties were assessed. The main results showed that compound layering of B. linearis is possible with compost addition. The growth of new roots and layering branches was significantly improved by either 30% or 50% compost addition into tailings, due to chemical improvements of substrate (higher nutrients and pH and decreased copper bioavailability). The study confirms that the compound layering of B. linearis may be an effective and novel technique for speeding the reclamation of post-operative mine tailings, which is improved by the incorporation of compost.

Predation shapes marine benthic communities and affects prey species population dynamics in tropic and temperate coastal systems. However, information on its magnitude in systematically understudied Arctic coastal habitats is scarce. To test predation effects on the diversity and structure of Arctic benthic communities, we conducted caging experiments in which consumers were excluded from plots at two intertidal sedimentary sites in Svalbard (Longyearbyen and Thiisbukta) for 2.5 months. Unmanipulated areas served as controls and partial (open) cages were used to estimate potential cage effects. At the end of the experiment, we took one sediment core from each plot and quantified total biomass and the number of each encountered taxon. At both sites, the experimental exclusion of predators slightly changed the species composition of communities and had negligible effects on biomass, total abundance, species richness, evenness, and Shannon Index. In addition, we found evidence for cage effects, and spatial variability in the intensity of the predation effects was identified. Our study suggests that predators have limited effects on the structure of the studied intertidal macrobenthic Arctic communities, which is different from coastal soft‐bottom ecosystems at lower latitudes.

Although Quintero-Puchuncaví Bay, Chile, is a coastal area historically known to be subject to multiple industrial pressures, few studies have focused on the associated risks to marine ecosystems and, through edible species, to human health. We studied concentrations of Cd, Cr, Cu, Mn, Pb, V, Zn, and Hg in marine species and sediments from Quintero-Puchuncaví Bay and a reference site. Results were compared with seafood safety guidelines, and target hazard quotients (THQs) were evaluated. Sediments and biota from the impacted area generally exhibited higher metal concentrations. Zinc (Zn) and copper (Cu) levels were the highest across all species, particularly in crustaceans, reflecting both physiological requirements and anthropogenic inputs. Cadmium (Cd) concentrations were higher in pelagic species from the impacted bay, but no differences were found in sediments or benthic species, suggesting the influence of upwelling conditions. Comparison with seafood safety guidelines revealed that Cd and Pb concentrations exceeded permissible limits in crabs, fish, and mussel species, and THQ ≥ 1 values were found for Cd concentrations in benthic species from the impacted bay, highlighting potential risks to consumers. The absence of permissible thresholds for certain environmentally relevant metals in Chilean regulations underscores the need to align with international standards, certainly to protect coastal ecosystems and human health.

The rapid expansion of seawater reverse osmosis (SWRO) desalination has raised concern about the effects of brine discharges on coastal marine ecosystems. This study evaluated stress biomarkers in two benthic species with contrasting physiological strategies, the red seaweed Rhodymenia corallina and the sea anemone Anthothoe chilensis, following field transplantation near a desalination brine discharge in northern Chile. Biomarkers of photosynthetic performance, oxidative stress, antioxidant defense, and osmoregulation were assessed after 24 h, 48 h, and 5 d of exposure. R. corallina showed limited photosynthetic changes, moderate oxidative damage, and reduced antioxidant reserves, whereas A. chilensis showed reduced oxidative damage and maintained antioxidant and osmotic homeostasis. The Biomarker Response Index (BRI) revealed moderate alteration at 24 h followed by lower scores at later times. These distinct response patterns reveal marked species-specific sensitivity to brine exposure and support the value of integrating multiple biomarkers to characterize physiological responses. Given their ecological relevance and suitability for field transplantation in desalination-impacted areas, these findings support the evaluation of R. corallina and A. chilensis as candidate biomonitors for desalination environmental monitoring.