Mg. Gonzalez-Sepulveda, Elizabeth

2018, Leclerc, Jean-Charles, Viard, Frédérique, Gonzalez-Sepulveda, Elizabeth, Diaz-Peralta, Christian, Neira Hinojosa, José, Pérez Araneda, Claudia, Silva, Francisco, Brante-Ramirez, Antonio

Growing coastal urbanization together with the intensification of maritime traffic are major processes explaining the increasing rate of biological introductions in marine environments. To investigate the link between international maritime traffic and the establishment of non-indigenous species (NIS) in coastal areas, biofouling communities in three international and three nearby local ports along 100 km of coastline in south-central Chile were compared using settlement panels and rapid assessment surveys. A larger number of NIS was observed in international ports, as expected in these ‘invasion hubs’. However, despite a few environmental differences between international and local ports, the two port categories did not display significant differences regarding NIS establishment and contribution to community structure over the studied period (1.5 years). In international ports, the free space could be a limiting factor for NIS establishment. The results also suggest that local ports should be considered in NIS surveillance programs in Chile.

2019, Tume-Zapata, Pedro, Gonzalez-Sepulveda, Elizabeth, Reyes, Felipe, Fuentes Espoz, Juan Pablo, Roca, Nuria, Bech, Jaume, Medina, Guillermo

Urban soils are a key component of urban ecosystems as they support biodiversity, provide foundation for infrastructure and play an important role in maintaining the environmental quality, being both a sink and a source of pollutants that have an effect in human health. The objectives of this study were (1) to determine the concentrations background of As, Co, Cr, Cu, Ni, Pb, V and Zn in the urban soils of Hualpen (Chile); (2) to assess the level of contamination in the urban soil based on different pollution indices; (3) to identify natural or anthropogenic sources in order to determine a spatial pattern of the pollutants and (4) to assess the health risks of trace metals in surface soils of Hualpen. A total of 153 samples were collected from the study area as follows: 51 topsoil samples (TS) (0–10 cm), 51 subsoil samples (SS) (10–20 cm) and 51 deep soil samples (DS) (150 cm). Multivariate statistics combined with spatial analysis were implemented in order to distinguish the sources. Several simple and robust statistical methods were applied to datasets in order to explore their potential in the evaluation of a useful and robust background values. The degree of contamination along with pollution indices were also evaluated. The median soil pseudo total concentrations of the elements were as follows: As 3 mg kg−1, Co 15 mg kg−1, Cr 14 mg kg−1, Cu 25 mg kg−1, Ni 36 mg kg−1, Pb 5 mg kg−1, V 97 mg kg−1 and Zn 51 mg kg−1. Multivariate analysis suggests that Cr, Pb, V and Zn are contributed by external sources. The spatial distribution of these elements displays a spatial pattern extending along industrial environments and emission sources. While the other elements show a spatial pattern with a few anthropogenic hot spots dispersed across Hualpen, they were influenced by both anthropogenic and geogenic inputs. The estimate background values determined with the DS samples with median absolute deviation (MAD) method were for As 5 mg kg−1, Co 20 mg kg−1, Cr 18 mg kg−1, Cu 33 mg kg−1, Ni 45 mg kg−1, Pb 3 mg kg−1, V 108 mg kg−1 and Zn 48 mg kg−1. The ecological indices register a moderate to considerable contamination in some soil samples. It was noted that the soils of Hualpen pose no carcinogenic risk, neither by inhalation nor by ingestion.

2018, Tume-Zapata, Pedro, Gonzalez-Sepulveda, Elizabeth, King-St-Onge, Robert, Cuitiño, Lucas, Bech, Jaume, Roca, Núria

Purpose: The objectives of this study were (1) to determine the concentrations and background concentrations of Ba, Co, Cr, Mn, and Ni in the urban soils of Talcahuano (Chile); (2) assess the level of contamination in the urban soils based on different pollution indexes; and (3) to identify natural or anthropogenic sources in order to obtain a spatial distribution of the pollutants. Material and methods: A total of 420 samples were collected from the study area as follows: 140 topsoil samples (TS) (0–10 cm), 140 subsoil samples (SS) (10–20 cm), and 140 deep soil samples (DS) (150 cm). The soils were characterized, and the concentrations of Ba, Co, Cr, Mn, and Ni were analyzed by atomic absorption photospectrometry following aqua regia digestion. Correlations and principal component analysis combined with spatial analysis were implemented in order to distinguish the sources and their classification as geogenic or anthropogenic. Several simple and robust statistical methods were applied to datasets in order to explore their potential in the evaluation of a useful and robust background values. The degree of contamination along with the geoaccumulation index, enrichment factor, and contamination factor were also evaluated. Results and discussion: The median concentrations obtained for various elements includes Ba 461 mg kg−1, Co 82.7 mg kg−1, Cr 134 mg kg−1, Mn 311 mg kg−1, and Ni 56.1 mg kg−1. In general, the concentrations of Ba, Co, Cr, Mn, and Ni decrease with depth. Correlations and principal component analysis suggest that Cr, Mn, and Ni are contributed by external sources. The spatial distribution of Cr, Mn, and Ni in TS displays a spatial pattern extending along industrial environments and emission sources. Conclusions: The estimated background values determined with the iterative 2σ-technique includes 536 mg kg−1 for Ba, 95.9 mg kg−1 for Co, 208 mg kg−1 for Cr, 464 mg kg−1 for Mn, and 90.5 mg kg−1 for Ni. The geochemical index, enrichment factor, and the contamination factor register a moderate to considerable contamination in some soil samples.

2015, Ahumada, Ramón, Gonzalez-Sepulveda, Elizabeth, Diaz-Peralta, Christian, Silva, Nelson

The spatial distribution of heavy metals content (Ba, Cd, Cu, Pb, Sr and Zn) in sediments of the Baker Fjord and surrounding channels in the central region of the Chilean fjords (47°45'S, 48°15'S) is analyzed. The aim of the study was characterized the patterns of abundance and distribution of these metals in surface sediments. The area corresponds to a poorly studied zone with low human activity. Distribution patterns would be influenced by rainfall conditions (local erosion), fluvial (continental sediments carried by rivers), glacier (glacier flour) and estuarine circulation. Cluster analysis allows differentiation among the sampled sites and group with similar characteristics. Finally, the concentrations found were contrasted with average values of metamorphic rocks and show with some certainty that the values found for calendar for this area and the greatest concentrations are the result of natural enrichment.

2018, Tume-Zapata, Pedro, Gonzalez-Sepulveda, Elizabeth, King-St-Onge, Robert, Monsalve, Victor, Roca, Núria, Bech, Jaume

The objective of this study is to ascertain the spatial distribution of Cu, Pb and Zn in order to determine the degree of contamination in urban soils from Talcahuano (Chile) and to identify the influence of possible contamination sources. A total of 420 samples were collected from the study area based on the following criteria: 140 topsoil samples (TS) (0–10 cm), 140 subsoil samples (SS) (10–20 cm) and 140 deep soil samples (DS) (150 cm). The soils were characterized for their physical characteristics such as grain size distribution, pH, organic matter content etc. and the concentrations of Cu, Pb and Zn were analyzed by Atomic Absorption Photospectrometry following Aqua Regia digestion. Correlations combined with spatial analysis were implemented in order to distinguish the sources of the trace metals and whether they are geogenic or anthropogenic of origin. Several simple and robust statistical methods were applied to the data sets in order to evaluate useful and robust background values. The degree of contamination along with the geoaccumulation index, enrichment factors and contamination factors were also evaluated. The median concentrations obtained for the studied trace metals includes: Cu 23.1 mg kg− 1, Pb 10.2 mg kg− 1 and Zn 56.7 mg kg− 1. In general, the concentrations of Cu, Pb and Zn decrease with depth however, in certain sites the subsoil samples (SS) levels show higher concentrations than topsoil samples (TS). A possible explanation could be related to the uncontrolled clandestine landfill sites using both construction material debris and/or industrial solid wastes. Correlation analysis suggests that Cu, Pb and Zn are contributed by external sources. The spatial distribution of Cu, Pb and Zn in topsoil samples (TS) displays a spatial pattern extending along major roadway environments and emission sources. Estimated background values determined with the iterative 2σ-technique yields 43.7 mg kg− 1 for Cu, 17.5 mg kg− 1 for Pb and 91.7 mg kg− 1 for Zn respectively. The geochemical index, enrichment factor and the contamination factor all register a moderate to high contamination level in some of the soil samples.