Evolution of building façade road traffic noise levels in Flanders

The evolution of daytime fa?ade noise levels by road traffic at 250 dwellings in Flanders is assessed. Three identical man-operated measurement campaigns have been conducted in the years 1996, 2001 and 2009, during fall. A practical methodology has been developed, based on short time noise measurements and context observations at these locations. The uncertainty introduced by short-term sampling has been quantified as a function of the noise level. Furthermore, a correction is proposed for measuring at a random moment during daytime. Analysis of the data showed that road traffic noise levels hardly changed globally over this period of 13 years. The distribution of changes in noise level at corresponding measurement locations is nevertheless rather wide-all improvements are equally compensated by increases in noise levels at other locations. The percentage of the dwelling fa?ades exposed to daytime noise levels above 65 dBA has increased slightly between 1996 and 2001, but seems to stagnate in 2009. In spite of the increased interest and actions of policy makers during the past decades, noise exposure caused by road traffic at dwelling fa?ades is a persistent problem.     

Methods,fluxes and sources of gas phase alkyl nitrates in the coastal air

The daily and seasonal atmospheric concentrations, deposition fluxes and emission sources of a few C3–C9 gaseous alkyl nitrates (ANs) at the Belgian coast (De Haan) on the Southern North Sea were determined. An adapted sampler design for low- and high-volume air-sampling, optimized sample extraction and clean-up, as well as identification and quantification of ANs in air samples by means of gas chromatography mass spectrometry, are reported. The total concentrations of ANs ranged from 0.03 to 85 pptv and consisted primarily of the nitro-butane and nitro-pentane isomers. Air mass backward trajectories were calculated by the Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model to determine the influence of main air masses on AN levels in the air. The shorter chain ANs have been the most abundant in the Atlantic/Channel/UK air masses, while longer chain ANs prevailed in continental air. The overall mean N fluxes of the ANs were slightly higher for summer than those for winter-spring, although their contributions to the total nitrogen flux were low. High correlations between AN and HNO₂ levels were observed during winter/spring. During summer, the shorter chain ANs correlated well with precipitation. Source apportionment by means of principal component analysis indicated that most of the gas phase ANs could be attributed to traffic/combustion, secondary photochemical formation and biomass burning, although marine sources may also have been present and a contributing factor.     

Evaluating exposure to land degradation in association with repetitive armed conflicts in North Lebanon using multi-temporal satellite data

Repetitive armed conflicts may be directly and indirectly responsible for severe biophysical modification to the environment. This, in turn, makes land more susceptible to degradation. Mapping and monitoring land degradation are essential for designing and implementing post-conflict recovery plans and informed policy decisions. The aim of this work was to evaluate the effect of repetitive armed conflicts on land degradation along the coastal zone of North Lebanon using multi-temporal satellite data. The specific objectives were to (1) identify a list of indicators for use in conjunction with satellite remote sensing, (2) monitor land cover change throughout repetitive events of armed conflicts and (3) model the effect of repetitive armed conflicts on land degradation. The methodology of work comprised the use of multi-temporal Landsat images and literature review data in GEographic Object-Based Image Analysis (GEOBIA) approach. The work resulted in the development of (1) a list of indicators to be employed, (2) land cover change detection maps with the use of multi-temporal Landsat images and, consequently, a fire risk associated with changes in vegetation cover throughout repetitive armed conflict events, and (3) an integrated approach for modelling the effect of repetitive armed conflicts on land degradation with the use of a composite land degradation index (CLDI). The final synthetic map showed four classes of exposure to land degradation associated with repetitive armed conflicts. Data collected from field visits showed that the final classification results highly reflected (average of 90 %) the effect of repetitive armed conflicts on the different classes of exposure to land degradation.     

Airborne particulate matter and BTEX in office environments

Total suspended particulate (TSP), PM(2.5) and BTEX were collected in nine offices in the province of Antwerp, Belgium. Both indoor and outdoor aerosol samples were analysed for their weight, elemental composition, and water-soluble fraction. Indoor TSP and PM(2.5) concentrations ranged from 7-31 microg m(-3) and 5-28 microg m(-3), with an average of 18 and 11 microg m(-3), respectively. Of all the elements analysed in indoor TSP, more than 95% was represented by Al, Si, K, Ca, Fe, Cl and S, accounting for 12% of the TSP by mass. The other elements showed significant enrichment relative to the earth's crust. The water-soluble ionic fraction accounted for almost 30% of the sampled indoor TSP by weight, and was enriched by anthropogenic activities. It was shown that the indoor PM levels varied among the offices, depending on the ventilation pattern, location, and occupation density of the office. Indoor BTEX levels ranged together from 5-47 microg m(-3) and were considerably higher than the corresponding outdoor levels. It was observed that some recently constructed and renovated buildings were clearly burdened with elevated levels for toluene, ethyl benzene, and xylenes, while outdoor air was found to be the main source for BTEX levels at the 'older' offices.     

Pesticide residues in soils, sediments, and vegetables in the Red River Delta, northern Vietnam

This study assessed pesticide residues in soils, sediments, and vegetables in the Xuan Khe and Hop Ly communes located along the Chau Giang River in the Red River Delta, northern Vietnam. Samples were collected from agricultural areas within and outside of embankments built to prevent flooding. In Xuan Khe, the soils outside of the embankment were more clayey with higher organic matter contents compared with the inside, due to selective deposition during river flooding. Many of the soils contained significant amounts of pesticides including dichlorodiphenyltrichloroethane (DDT), dicofol, isoprothiolane, and metalaxyl although their levels were below the maximum allowable concentration set by the Vietnamese government. The spectrum of DDT derivatives found suggested that the source of DDTs was not contaminated dicofol. Soils in Hop Ly resembled soils in Xuan Khe but were relatively sandy; one field showed appreciable contents of DDT derivatives. The ratios of (p,p ^′-dichlorodiphenyldichloroethylene + p,p ^′-dichlorodiphenyldichloroethane)/∑DDT in the surface and subsurface soils in Hop Ly were 0.34 and 0.57, suggesting that the DDTs originated from recent application. Pesticide residues in soils were not likely to translocate into vegetable crops, except for metalaxyl. High concentrations of cypermethrins in kohlrabi leaves could be ascribed to foliar deposition.     

Analysis of indoor gaseous formic and acetic acid, using radial diffusive samplers

A diffusive sampling method for the determination of gaseous acetic and formic acids, using a radial symmetry diffusive sampler, has been optimised for a 7-day exposure time in this study. Sampling rate determinations were performed on data obtained from a dynamic exposure chamber, simulating the indoor conditions of an empty, closed, room, at room temperature and minimal wind speed. Analysis has been performed by means of ion chromatography. The sampling rates for formic acid concentrations of 128 microg m(-3) and 1248 microg m(-3) were determined to be 91.2 +/- 3.9 ml min(-1) and 111.6 +/- 2.8 ml min(-1), respectively. The acetic acid sampling rate was independent of the concentration in the range 160 microg m(-3)-1564 microg m(-3), and amounted to 97.3 +/- 3.1 ml min(-1). Experimentally determined sampling rates showed deviations of 3% for acetic acid, and 3-21% for formic acid, in relation to theoretically derived values. The blank values were as low as 1.69 +/- 0.07 microg for formic acid and 1.21 +/- 0.14 microg for acetic acid, and detection limits lower than 0.5 microg m(-3) could be achieved, which is an improvement of 98-99% compared to previously validated diffusive sampling methods. This study describes the first step of an extended validation program in which the applicability of these types of samplers for the measurement of organic acids will be validated and optimised for the environmental conditions typical for museum showcases.     

Presence of pesticide residues on produce cultivated in Suriname

Agricultural pesticides are widely used in Suriname, an upper middle-income Caribbean country located in South America. Suriname imported 1.8 million kg of agricultural pesticides in 2015. So far, however, national monitoring of pesticides in crops is absent. Reports from the Netherlands on imported Surinamese produce from 2010 to 2015 consistently showed that samples exceeded plant-specific pesticide maximum residue limits (MRLs) of the European Union (EU). Consumption of produce containing unsafe levels of pesticide residues can cause neurological disorders, and particularly, pregnant women and children may be vulnerable. This pilot study assessed the presence of pesticide residues in commonly consumed produce items cultivated in Suriname. Thirty-two insecticides (organophosphates, organochlorines, carbamates, and pyrethroids) and 12 fungicides were evaluated for their levels in nine types of produce. Pesticide residue levels exceeding MRLs in this study regarded cypermethrin (0.32 μg/g) in tomatoes (USA MRL 0.20 μg/g), lambda-cyhalothrin (1.08 μg/g) in Chinese cabbage (USA MRL 0.40 μg/g), endosulfan (0.07 μg/g) in tannia (EU MRL 0.05 μg/g), and lindane (0.02 and 0.03 μg/g, respectively) in tannia (EU MRL 0.01 μg/g). While only a few pesticide residues were detected in this small pilot study, these residues included two widely banned pesticides (endosulfan and lindane). There is a need to address environmental policy gaps. A more comprehensive sampling and analysis of produce from Suriname is warranted to better understand the scope of the problem. Preliminary assessments, using intake rate, hazard quotient, and level of concern showed that it is unlikely that daily consumption of tannia leads to adverse health effects.     

Settlement of <Emphasis Type="Italic">Macoma balthica</Emphasis> larvae in response to benthic diatom films

The role of multi-species benthic diatom films (BDF) in the settlement of late pediveliger larvae of the bivalve Macoma balthica was investigated in still-water bioassays and multiple choice flume experiments. Axenic diatom cultures that were isolated from a tidal mudflat inhabited by M. balthica were selected to develop BDF sediment treatments characterized by a different community structure, biomass, and amount of extracellular polymeric substances (EPS). Control sediments had no added diatoms. Although all larvae settled and initiated burrowing within the first minute after their addition in still water, regardless of treatment, only 48–52% had completely penetrated the high diatom biomass treatments after 5 min, while on average 80 and 69% of the larvae had settled and burrowed into the control sediments and BDF with a low diatom biomass (<3.5 μg Chl a g⁻¹ dry sediment), respectively. The percentage of larvae settling and burrowing into the sediment was negatively correlated with the concentration of Chl a and EPS of the BDF. This suggests higher physical resistance to bivalve penetration by the BDF with higher diatom biomass and more associated sugar and protein compounds. The larval settlement rate in annular flume experiments at flow velocities of 5 and 15 cm s⁻¹ was distinctly lower compared to the still-water assays. Only 4.6–5.8% of the larvae were recovered from BDF and control sediments after 3 h. Nonetheless, a clear settlement preference was observed for BDF in the flume experiments; i.e., larvae settled significantly more in BDF compared to control sediments irrespective of flow speed. Comparison with the settlement of polystyrene mimics and freeze-killed larvae led to the conclusion that active selection, active secondary dispersal and, at low flow velocities (5 cm s⁻¹), passive adhesion to the sediment are important mechanisms determining the settlement of M. balthica larvae in estuarine biofilms.     

The role of the Alliance of Small Island States (AOSIS) in the negotiation of the United Nations Framework Convention on Climate Change (UNFCCC)

The United Nations Framework Convention on Climate Change (UNFCCC), which was signed by some 153 countries at the Earth Summit in Rio de Janeiro, Brazil in 1992, represented a singular triumph for the geographically dispersed group of island states and low-lying coastal developing countries, located in the Pacific, Atlantic and Indian Oceans, as well as in the Caribbean, South China and Mediterranean Seas, and known as the Alliance of Small Island States (AOSIS). This article focuses on the goals of AOSIS during the negotiations leading up to the adoption of the UNFCCC. For the first time in the history of the United Nations, a group of small states, hitherto relegated to the sidelines, was able to develop a specific negotiating agenda addressing areas which are of overriding concern to them and succeeded in having those concerns incorporated in a legally binding Convention of historic importance. As this article reveals, AOSIS set itself 12 negotiating goals during the negotiating rounds leading up to the UNFCCC, and 10 of these 12 goals were realized. Nevertheless, AOSIS, whose member states are most vulnerable to the possible adverse effects of climate change, was particularly concerned about those provisions of the UNFCCC that were either watered-down significantly, made largely meaningless or excluded altogether. These include: the absence of definite targets or specific timetables for the significant reduction of carbon dioxide by the industrialized countries of the North; the lack of permanent and clear financing arrangements in particular the lack of definitive financial provisions for adaptive response measures to the adverse impacts of climate change such as sea-level rise; and the absence of a specific provision for the implementation of coastal zone management schemes for those countries most vulnerable to sea-level rise. As the UNFCCC moves into the implementation phase, AOSIS should and must build on its past success. To do so, it will need to develop clearly defined initiatives aimed at strengthening the commitments for financing and insurance, and to seek inclusion of a provision to develop and finance coastal zone management schemes for the most vulnerable small states. While the article covers the AOSIS negotiating period up to and including the Earth Summit in June 1992, we nevertheless postulate some possible objectives which the AOSIS group might wish to consider in what is sure to be an intensive post-Earth Summit phase of the UNFCCC, leading up to the first Conference of the Parties of that Convention.