Erratum to: 36th International Symposium on Intensive Care and Emergency Medicine

[This corrects the article DOI: 10.1186/s13054-016-1208-6.]

PORTRAYING CHEMICAL PROPERTIES OF BEDROCK FOR WATER QUALITY AND ECOSYSTEM ANALYSIS: AN APPROACH FOR THE NEW ENGLAND REGION PORTRAYING CHEMICAL PROPERTIES OF BEDROCK FOR WATER QUALITY AND ECOSYSTEM ANALYSIS: AN APPROACH FOR THE NEW ENGLAND REGION

ABSTRACT A classification scheme has been developed to describe bedrock geologic rock units in terms of lithologic units with similar chemical features (termed lithochemical units) that portray the relative reactivity of their constituent minerals to dissolution and other weathering reactions. The lithochemical classification, as developed for the New England Region, consists of 26 lithologic types, which are defined on mineralogy, weathering characteristics, and structural setting. The 26 units can be summarized into 6 major categories, arranged in order of decreasing weatherability or attack by natural waters: (1) carbonate-rich rocks, (2) clastic sedimentary rocks restricted to rift basins, (3) mafic igneous rocks and their metamorphic equivalents, (4) ultramafic rocks, (5) metamorphosed, noncalcareous clastic sedimentary rocks, and (6) felsic igneous and plutonic rocks and their metamorphic equivalents. This classification was developed to provide the USGS National Water Quality Assessment (NAWQA) Program with a scheme to use bedrock geologic data for analysis of the water-quality characteristics of surface water and shallow ground water

A Comparison of Data-Driven Groundwater Vulnerability Assessment Methods

Increasing availability of geo-environmental data has promoted the use of statistical methods to assess groundwater vulnerability. Nitrate is a widespread anthropogenic contaminant in groundwater and its occurrence can be used to identify aquifer settings vulnerable to contamination. In this study, multivariate Weights of Evidence (WofE) and Logistic Regression (LR) methods, where the response variable is binary, were used to evaluate the role and importance of a number of explanatory variables associated with nitrate sources and occurrence in groundwater in the Milan District (central part of the Po Plain, Italy). The results of these models have been used to map the spatial variation of groundwater vulnerability to nitrate in the region, and we compare the similarities and differences of their spatial patterns and associated explanatory variables. We modify the standard WofE method used in previous groundwater vulnerability studies to a form analogous to that used in LR; this provides a framework to compare the results of both models and reduces the effect of sampling bias on the results of the standard WofE model. In addition, a non-linear Generalized Additive Model has been used to extend the LR analysis. Both approaches improved discrimination of the standard WofE and LR models, as measured by the c-statistic. Groundwater vulnerability probability outputs, based on rank-order classification of the respective model results, were similar in spatial patterns and identified similar strong explanatory variables associated with nitrate source (population density as a proxy for sewage systems and septic sources) and nitrate occurrence (groundwater depth).JRC.H.6-Digital Earth and Reference Dat

Containing Arsenic-Enriched Groundwater Tracing Lead Isotopic Compositions Of Common Arsenical Pesticides In A Coastal Maine Watershed Containing Arsenic-Enriched Ground Water

Arsenical pesticides and herbicides were extensively used on apple, blueberry, and potato crops in New England during the first half of the twentieth century. Lead arsenate was the most heavily used arsenical pesticide until it was officially banned. Lead arsenate, calcium arsenate, and sodium arsenate have similar Pb isotope compositions: 208Pb/207Pb = 2.3839-2.4722, and 206Pb/207Pb = 1.1035-1.2010. Other arsenical pesticides such as copper acetoarsenite (Paris green), methyl arsonic acid and methane arsonic acid, as well as arsanilic acid are widely variable in isotope composition. Although a complete understanding of the effects of historical use of arsenical pesticides is not available, initial studies indicate that arsenic and lead concentrations in stream sediments in New England are higher in agricultural areas that intensely used arsenical pesticides than in other areas. The Pb isotope compositions of pesticides partially overlap values of stream sediments from areas with the most extensive agricultural use. The lingering effects of arsenical pesticide use were tested in a detailed geochemical and isotopic study of soil profiles from a watershed containing arsenic-enriched ground water in coastal Maine. Acid-leach compositions of the soils represent lead adsorbed to mineral surfaces or held in soluble minerals (Fe- and Mn-hydroxides, carbonate, and some micaceous minerals), whereas residue compositions likely reflect bedrock compositions. The soil profiles contain labile Pb (acid-leach) showing a moderate range in 206Pb/207Pb (1.1870-1.2069), and 208Pb/207Pb (2.4519-2.4876). Isotope values vary as a function of depth: the lowest Pb isotope ratios (e.g., 208Pb/206Pb) representing labile lead are in the uppermost soil horizons. Lead contents decrease with depth in the soil profiles. Arsenic contents show no clear trend with depth. A multi-component mixing scheme that included lead from the local parent rock (Penobscot Formation), lead derived from combustion of fossil fuels, and possibly lead from other anthropogenic sources (e.g., pesticides), could account for Pb isotope variations in the soil profiles. In agricultural regions, our preliminary data show that the extensive use of arsenical pesticides and herbicides can be a significant anthropogenic source of arsenic and lead to stream sediments and soils