4 research outputs found
Precisions on the age of the Margas del Forcall Fm in the Oliete sub-basin (NE Iberian Range, Spain) by means of ammonoids and nautiloids
Ammonoids and nautiloids from Margas del Forcall Formation, located in the Oliete sub-basin (Iberian
Chain), were studied. Taphonomic, sedimentologic and biostratigraphic analyses were carried out. The
fossil record of cephalopods is especially abundant in a layer made up of reddish limestone with elongated
nodules that are usually covered by a ferruginous-manganese crust. These nodules are embedded in a
micritc matrix where infaunal tiering is largely preserved. The biostratigraphic study has allowed recognizing
Hambrovi Subzone and proposing a new bioestratigraphic position for this stratigraphic interva
Assessment of Soil Heavy Metal Pollution and the Ecological Risk in an Agricultural Area from Sánchez RamÃrez Province, Dominican Republic
Heavy metal pollution in agricultural soils is one of the main problems in agricultural production worldwide, which threatens human health and the environment. To evaluate the pollution levels of heavy metals and the ecological risks in an agricultural area from Sánchez RamÃrez Province, Dominican Republic, the concentration levels of heavy metals (Fe, Mn, Cr, Ni, Cu, Zn, Pb, and As) were measured using energy-dispersive X-ray fluorescence spectroscopy (EDXRF). Several pollution indices, including the geo-accumulation index (Igeo), enrichment factor (EF), and single pollution index (PI), were used to investigate the pollution status. The spatial distribution of different heavy metals in the studied soils was also determined. The mean concentrations of Fe, Mn, Cr, Ni, Cu, Zn, Pb, and As were 73735, 1616, 426; 34; 20; 200; 43; and 5 mg kg−1, respectively. These results indicated that the mean concentration of Cr, Cu, Zn, and Pb exceeded FAO-recommended levels for healthy agricultural soils. However, the potential ecological risks assessment indicated a low-risk status. The results obtained could help improve soil–rice–environment management practices and prevent heavy metal pollution in this type of production system, protecting the health of the local population and the environment
Projected Hydroclimate Changes on Hispaniola Island through the 21st Century in CMIP6 Models
Climate change might increase the frequency and severity of longer-lasting drought in the Caribbean, including in Hispaniola Island. Nevertheless, the hydroclimate changes projected by the state-of-the-art earth system models across the island remain unknown. Here, we assess 21st-century changes in hydroclimate over Hispaniola Island using precipitation, temperature, and surface soil moisture data from the 6th Phase of the Coupled Model Intercomparison Project (CMIP6). The resulting analysis indicates, as with the previous 5th Phase of CMIP (CMIP5) models, that Hispaniola Island might see a significant drying through the 21st century. The aridity appears to be robust in most of the island following the Shared Socioeconomic Pathways (SSP) 5–8.6, which assumes the “worst case” greenhouse gas emissions into the atmosphere. We find a significant reduction in both annual mean precipitation and surface soil moisture (soil’s upper 10 cm), although it appears to be more pronounced for precipitation (up to 26% and 11% for precipitation and surface soil moisture, respectively). Even though we provide insights into future hydroclimate changes on Hispaniola Island, CMIP6’s intrinsic uncertainties and native horizontal resolution precludes us to better assess these changes at local scales. As such, we consider future dynamical downscaling efforts that might help us to better inform policy-makers and stakeholders in terms of drought risk