Four-decade (1977-2017) landscape tale of tourist reservoir hotspot El Piñol-Guatapé, Colombia.

Efficient management of land use/land cover (LULC) features is vital for a balanced sustainable ecosystem. Thus, this work aimed to document the LULC changes in the less studied El Peñol-Guatapé reservoir, Antioquia, Colombia, especially in the reservoir area due to the construction of a hydro-electric power plant. For this study, Landsat images of 1977, 1986, 1997, and 2017 were used and the results indicated an increase in the settlement area and road networks by 0.10 and 0.60%, respectively, while during 1986 to 2017, cropland, plantation, dense forest, and open forest areas presented an increase of 0.52, 1.06, 2.87 and 2.61%, respectively. However, the marshy vegetation, scrub forest and fallow land decreased to - 0.51, - 3.79 and - 4.29%, respectively, in the same period. The water body before and after the completion of reservoir project denoted an increase from 13.1 km2 in 1977 to 45.7 km2 in 1986. This study provides a first-hand report on LULC dynamics in this tourism dominated municipalities that will serve as a reference for ecosystem management to reconcile the conflicts between different LULC classes in ecologically enriched regions.

Rare earth element enrichments in beach sediments from Santa Rosalia mining region, Mexico: An index-based environmental approach.

Baseline data on concentration, fractionation, pollution level and ecological risk index for seventeen beach sediments from Santa Rosalia mining region of Baja California Sur, Mexico were assessed. Higher concentrations of Rare Earth Elements (REEs) (mean. 341.49 µg/g) indicated that it is higher than most of the mining regions around the world. Normalization pattern showed enrichment of Eu (>4) and calculated geochemical indices revealed that light and middle REEs are moderately polluted with most of the sampling points located closer to the river discharge. Potential Ecological Risk Index (PERI) showed that Eu (20.2), Tb (20.88), and Lu (28.57) pose moderate ecological risk to the soil at selected stations (10, 11, 15 and 16) with a risk index value ranging from 245 to 359. Pearson's correlation matrix suggested that all REEs are highly correlated (r2 0.95) with each other having similar geochemical characteristics and indicating identical source due to continuous mining activity.

Coastline variability of several Latin American cities alongside Pacific Ocean due to the unusual "Sea Swell" events of 2015.

This study aims to report the short-term coastline dynamics and inundation limits of coastal cities along the Eastern Pacific due to the sea swell events that occurred during April to May 2015. The multi-temporal satellite datasets from Landsat such as Enhanced Thematic Mapper (L7 ETM+) and Operational Land Imager/Thermal Infrared Sensor (L8 OLI/TIRS) of different periods before and after the swell events were used to identify the shoreline changes. The satellite images were pre-processed using ERDAS imagine 9.2, and the coastline was digitized in ArcGIS 10.4.1 for ten cities spread across from Mexico to Chile (in Pacific coast) using the spectral water indices, and the shoreline change rate and erosion/accretion pattern at each transect were estimated using the statistical parameters embedded in Digital Shoreline Analysis System (DSAS). The maximum erosion and accretion were observed in El Salvador (268 m) and Huatulco (Mexico) (115 m), respectively. Likewise, the maximum inundation was observed in El Salvador with 268 m and Acapulco (Mexico) with 254 m, and the tide gauge data suggest a possible relation to the bathymetry and the geomorphological conditions of the coast. Overall, the results indicate that the Eastern Pacific Ocean side sea swell events has led to extreme coastal flooding in recent years due to the increase in the mean sea level and the unpredictable variation in El Niño/Southern Oscillation events. Graphical abstract.