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521.
During drinking water treatment and distribution, chlorine reacts with organic matter occurring in water to form various chlorination by-products (CBPs) such as trihalomethanes (THMs) and haloacetic acids (HAAs). This paper presents the occurrence of THMs and HAAs in different water distribution systems (DS) of the same region and their modelling for exposure assessment purposes. This study was conducted in eight DS supplying chlorinated water to the population of Québec City, Canada. These systems differ in type of water source (i.e. surface, ground or mixed water), in treatment applied at the plant, and in size and structure of the DS. Two spatio-temporal databases for THMs and HAAs were implemented, one for model development and the other for model validation. The analysis of the data demonstrates significant seasonal and spatial variations of these compounds. A multi-level statistical modelling approach was applied to estimate the ranges for occurrence of THMs and HAAs in the eight DS (i.e. a single model for the study region for each CBP species). The modelling approach integrates available or easily measurable parameters. For both THMs and HAAs, a two-level model considering a sampling-site random effect was selected among various models initially developed. The model capacity for estimating the presence of THMs and HAAs in drinking water and its usefulness for exposure assessment purposes in the studied region was demonstrated.  相似文献   
522.
Platanus is a major cause of pollen allergy in many Spanish cities. The present paper reports an analysis of Platanus pollen season throughout the Andalusia region (southern Spain), which has among the highest pollen counts and the highest incidence of Platanus-related allergies in Europe. The main aim was to analyze pollen season trends from 1992 to 2010 in Andalusia; models were also constructed to forecast the start of the season. Daily pollen counts were recorded using Hirst-type volumetric spore-traps. Pollen season start-dates were very similar at all sites, usually occurring in March. The pollen season was delayed over the study period. The Pollen-season duration and Pollen index generally increased throughout the study period. The starting date for temperature accumulation was around the 10th February, although the threshold temperatures varied by site. The regional model for Andalusia failed to provide sufficiently accurate results compared with sub-regional or local models. For modeling purposes, three sub-regions are recommended: Inland, East Coast and West Coast.  相似文献   
523.
This study aimed to evaluate the presence of ultraviolet filters (UV-Fs), benzotriazoles, pyrethroids and per- and polyfluoroalkyl substances (PFASs) in freshwater and wastewater from the northern Antarctic Peninsula region. All water samples analyzed contained UV-Fs residues and high concentrations were detected in anthropogenic impacted sites (< LOD up to 1300 ng/L). Likewise, benzotriazoles were detected in all water samples (< LOQ–920 ng/L). Regarding suspended particulate matter, almost all UV-Fs and all benzotriazoles were measured at concentrations ranging from < LOQ to 33 µg/g dry weight. Pyrethroids were also detected (< LOQ–250 ng/L) and their presence implies the existence of a gateway to the Antarctica Peninsula from other regions. The data confirmed the presence of PFASs (< LOD–7500 ng/L) in this area, in agreement with previous studies. In light of these results, extended monitoring in Antarctica should be carried out to perform a reliable environmental risk assessment leading to propose recommendations to minimize the anthropic impact.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01404-x) contains supplementary material, which is available to authorized users.  相似文献   
524.
Environmental Science and Pollution Research - Biomass burning from grassland, forests, and agricultural waste results in large amounts of gases and particles emitted to the atmosphere, which...  相似文献   
525.
During the 2007–2008 global food crisis, the prices of primary foods, in particular, peaked. Subsequently, governments concerned about food security and investors keen to capitalize on profit-maximizing opportunities undertook large-scale land acquisitions (LASLA) in, predominantly, least developed countries (LDCs). Economically speaking, this market reaction is highly welcome, as it should (1) improve food security and lower prices through more efficient food production while (2) host countries benefit from development opportunities. However, our assessment of the debate on the issues indicates critical voices in both the media and academic discourse. This article aims to provide a philosophical law and economics analysis. We draw on John Rawls’s Theory of Justice, focusing on Rawls’s background institutions for distributive justice (§43) to evaluate LASLA form an ethical angle. Approaching LASLA into Sub Saharan LDCs as a socio-economic reform redistributing land from the local population of LDCs to investors, we acknowledge that they bear a highly desirable potential. Often, though, they cannot be regarded as ethically correct in practice as the insignificant improvements for local populations and sometimes even human rights violations contradict Rawls’s principles of justice. Then investigating whether and how international law can help overcome the shortcomings, we conclude that even though respective mechanisms exist in the current state of international law, it is hardly possible that it will produce more just outcomes in the near future.  相似文献   
526.
527.
Because volcanic soils store large amounts of soil organic carbon (SOC), they play a far more important role in the carbon (C) cycle than their limited global coverage suggests. We analysed the C released as CO2 from a range of volcanic soils under natural conditions and analysed the influence of environmental variables (moisture and temperature), substrate availability (as assessed from the contents of various SOC fractions and the inputs of plant residues from litterfall), respiratory agents (roots, microorganisms and decomposing enzymes) and other pedological features of the topsoils (0–30 cm depth) on the CO2 efflux rates over a 2-year experimental period. High CO2 efflux rates (419 g C-CO2 m?2 y?1 as the average for Andisols) were obtained that were related to significant decreases in the amount of SOC stored. CO2 release was strongly controlled by soil moisture, although it was inhibited in the Andisols with the highest moisture levels (above 50 kg m?2 in topsoil). It was not responsive to the availability of decomposing microorganisms or enzymes and appeared more related to the inputs of easily decomposable plant residues than to the amount of either labile or recalcitrant SOC. Among the SOC pools, only the water-soluble C in saturated paste extracts (WSCse) of air-dried soil samples was consistently correlated with the CO2 efflux rates. The desiccation of Andisols appeared to induce the release of previously stabilised SOC, which was readily mineralised when the moisture conditions became favourable. The results of this study indicate that SOC storage in Andisols is highly vulnerable to drying-wetting processes even in unmanaged natural ecosystems and that microclimate conditions can be critical for successful C sequestration in these soils.  相似文献   
528.
529.
Journal of Material Cycles and Waste Management - Food waste is a serious problem worldwide. There is a lot of waste in the food sector, while we still have a significant percentage of people who...  相似文献   
530.
Previous studies have identified the tropopause height (TH) as a promising fingerprint of climatic change. In the present paper, we report variations in TH for the Eurasian region over the period 1973–1998 and analyse the influence of the Northern Annular Mode (NAM) on these variations. As previous studies indicate that the greatest increases in TH occur in the extratropics, we focused our attention on this area. We applied a set of homogenization procedures to radiosonde data and considered three different scenarios that take into account change points and the main volcanic eruptions over the study period. Our results demonstrate that the number of stations with positive TH trends is very sensitive to the quality of data and the methods used to remove inhomogeneities. Consequently, when change points were included in the analysis, the number of stations with positive trends decreased markedly. Furthermore, stratospheric NAM appears to control TH in stations located at latitudes higher than 55°N.Electronic supplementary materials  Supplementary material is available for this article at and is accessible to authorized users.  相似文献   
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