Sources and major biogeochemical pathways of organic matter in the mangrove system of Rufiji estuary

Fatty acids were extracted from the surface sediments (10 cm) of three sampling sites of Rufiji estuary to infer their sources and biogeochemical pathways. The fatty acids ranging from C₈ to C₂₄ were distinguished from this study, and were broadly classified into saturated (SFAs), monounsaturated (MUFAs) and polyunsaturated fatty acids (PUFAs). SFAs were found to be the major fraction at station 1 and 3 where as at station 2, MUFAs dominated. A total of 19 fatty acids with a total concentration of 64.91 μg/g dry weight were characterised at station 1. C_16:0 was the most abundant fatty acid contributing 21.94% of total fatty acids (TFAs). C_22:2 was the second most abundant, which accounted for 9.46% of TFAs. Fatty acids ranging from C₁₂ to C₂₄ were identified at station 2. C₂₀ fatty acid was the most abundant fatty acid contributing 21.94%, followed by C_16:0. At station 3, fatty acids ranging from C₈ to C₂₄ were obtained. The PUFA C_20:5n-3 was the most abundant fatty acid contributing 21.65%, followed by C_24:0 (15.00% of TFAs). The ratio of lower molecular weight (LMW) to higher molecular weight (HMW) biomarkers was used as an indicators to distinguish higher plants organic matter from algae-derived fatty acids.     

Bioclimatic modelling of current and projected climatic suitability of coffee (<Emphasis Type="Italic">Coffea arabica</Emphasis>) production in Zimbabwe

Coffee is an important commodity crop in Zimbabwe and many other African countries in terms of its contribution to local and national economies. Coffee production in terms of productivity and quality face severe constraints due to climate change. A study was therefore carried out to understand and quantify the potential impact of climate change on the coffee sector in Zimbabwe using a bioclimatic modelling approach. Current climatically suitable areas were identified and compared with those areas identified to be climatically suitable under projected 2050 climatic conditions. The projected climatic conditions were obtained from climate predictions of two models: CCSM4 model and HadGEM2 model. Coffee production was found to be mostly sensitive to precipitation factors as these were the most important in determining climatic suitability of coffee production in Zimbabwe. The modelling showed that current coffee suitability varies spatially between the four coffee producing districts in Zimbabwe. Chipinge district has the largest area climatically suitable for coffee production followed by Chimanimani district with Mutare district having the smallest. The modelling predicted that there will be a spatial and quantitative change in climatic suitability for coffee production in Zimbabwe by 2050. The greatest changes are projected for Mutare district where over three quarters according to the CCSM4 model and the entire district according to the HadGEM2 model will turn marginal for coffee production. A westward shift in climatic suitability of coffee was observed for Chipinge and Chimanimani district. The models predicted a loss of between 30,000 ha (CCSM4) and 50,000 ha (HadGEM2) in areas climatically suitable for coffee production by 2050 in Zimbabwe. These changes are likely to be driven by changes in the distribution of precipitation received in the coffee areas. The study presents possible adaptation measures that can be adopted by the coffee sector in Zimbabwe and the region to maintain coffee productivity under a changing climate.     

Financing Marine Protected Areas Through Visitor Fees: Insights from Tourists Willingness to Pay in Chile

Tourism is a financing mechanism considered by many donor-funded marine conservation initiatives. Here we assess the potential role of visitor entry fees, in generating the necessary revenue to manage a marine protected area (MPA), established through a Global Environmental Facility Grant, in a temperate region of Chile. We assess tourists’ willingness to pay (WTP) for an entry fee associated to management and protection of the MPA. Results show 97 % of respondents were willing to pay an entrance fee. WTP predictors included the type of tourist, tourists’ sensitivity to crowding, education, and understanding of ecological benefits of the MPA. Nature-based tourists state median WTP values of US$ 4.38 and Sun-sea-sand tourists US$ 3.77. Overall, entry fees could account for 10–13 % of MPA running costs. In Chile, where funding for conservation runs among the weakest in the world, visitor entry fees are no panacea in the short term and other mechanisms, including direct state/government support, should be considered.     

Photodegradation of an azo dye of the textile industry

An advanced oxidation treatment, UV/H2O2, was applied to an azo dye, Hispamin Black CA, widely used in the Peruvian textile industry. Rates of color removal and degradation of the dye have been evaluated. A strongly absorbing solution was completely decolorized after 35 min of treatment, and after 60 min an 82% reduction of the total organic carbon (TOC) was obtained. It has been found that the degradation rate increased until an optimum value, beyond which the reagent exerted an inhibitory effect. The degradation rate was also function of pH.     

Über ein langlebiges Zwischenprodukt der photochemischen Reaktion zwischen Jod und Oxalat

The Science of Nature -     

Environmental Monitoring of Benzene and Alkylated Benzene from Vehicular Emissions

The volatile organic pollutants from direct vehicular exhaust were trapped with activated charcoal, desorbed with carbon disulphide and analysed by GC/MS with tert-butyl benzene as an internal standard. A comparative study was made from the exhaust of 1000 cc, 1300 cc, 1600 cc cars, pickup, lorry(diesel), 125 cc and 70 cc motorbikes. The level of pollutants emitted were in the following order, motorbike(petrol) car(petrol) pickup(petrol) lorry(diesel). The range of highest emission (125 cc motorbike) to the lowest emission (lorry(diesel)) was of the order of 102 for benzene, 6×102 for ethyl benzene, 5×102 for toluene and 3×102 for xylenes. Among cars, those fitted with catalytic convertors emitted a lower level of benzene (2 to 3 times) when compared with those without catalytic convertors. Similar studies on the air in air-conditioned buses, non air-conditioned buses and three metres from the edge of the road shows that they have the same pollutant level. The level of these pollutant as compared to those from direct car exhaust are of the order of 102 times less for benzene, xylene and toluene and 103 times less for ethylbenzene. The levels of benzene, toluene, ethylbenzene and xylenes by the road side and in the buses were found to be lower than the exposure limits of ACGIH, OSHA and EH40.     

Process safety challenges for SMEs in China

While process safety regulations and standards have been in place in western countries for more than two decades, China has only recently started to officially embrace these issues with the adoption of its Process Safety Management (PSM) regulation AQ/T 3034-2010 (SAWS, 2010). However, compliance with this regulatory framework requires substantial resources and may therefore appear too complex to be efficiently implemented by small and medium sized enterprises (SMEs) in the chemical sector. This is of particular relevance as about 99% of chemical companies in China are SMEs, accounting for more than 80% of all chemical accidents. To address this issue, additional local regulations and planning activities related to process safety have been implemented in China, including the establishment of hundreds of chemical industry parks. Some of the process safety problems faced by chemical industry parks are identified and discussed in this paper. To help solve these problems, UNEP's “Responsible Production approach for Chemical Hazards Management along the Value-Chain” is introduced in this paper and suggested as a simplified PSM approach targeted specifically at SMEs which, regardless of handling hazardous chemicals in their daily operations, may not have the knowledge or capacity to efficiently implement PSM and may not fall in the scope of the PSM regulation AQ/T 3034-2010. By introducing PSM to SMEs in a more manageable way, relevant steps can be progressively implemented by companies towards full compliance with the current regulatory framework, contributing to increased safety in chemical industry parks in China.     

Atmospheric carbonaceous aerosols over grasslands of central Europe and a Boreal forest

A labour-intensive analytical technique was applied to atmospheric particulate matter samples collected in a German urban/industrial influenced grassland location (Melpitz) and in a Finnish forest area (Hyyti?l?) in order to achieve a detailed chemical speciation of the organic content. The representative nature of the solvent and water-extractable fractions was determined. The organic compounds identified in the solvent extracts are represented by primary compounds with both anthropogenic and biogenic origin, which mainly derive from the vegetation waxes and from petrogenic sources. Secondary products resulting from the oxidation of volatile organic compounds were also detected. The German meadow presented the highest levels of sugars and acidic compounds in the water extracts, whilst polyols were the most abundant class in the Finnish forest. The major compounds of these classes were malic acid, mannitol, arabitol, glucose and sucrose. Levoglucosan was also found in the water extract.     

Oxygen isotope fractionation between bird bone phosphate and drinking water

Oxygen isotope compositions of bone phosphate (δ¹⁸O_p) were measured in broiler chickens reared in 21 farms worldwide characterized by contrasted latitudes and local climates. These sedentary birds were raised during an approximately 3 to 4-month period, and local precipitation was the ultimate source of their drinking water. This sampling strategy allowed the relationship to be determined between the bone phosphate δ¹⁸O_p values (from 9.8 to 22.5‰ V-SMOW) and the local rainfall δ¹⁸O_w values estimated from nearby IAEA/WMO stations (from ?16.0 to ?1.0‰ V-SMOW). Linear least square fitting of data provided the following isotopic fractionation equation: δ¹⁸O_w = 1.119 (±0.040) δ¹⁸O_p ? 24.222 (±0.644); R ² = 0.98. The δ¹⁸O_p–δ¹⁸O_w couples of five extant mallard ducks, a common buzzard, a European herring gull, a common ostrich, and a greater rhea fall within the predicted range of the equation, indicating that the relationship established for extant chickens can also be applied to birds of various ecologies and body masses. Applied to published oxygen isotope compositions of Miocene and Pliocene penguins from Peru, this new equation computes estimates of local seawater similar to those previously calculated. Applied to the basal bird Confuciusornis from the Early Cretaceous of Northeastern China, our equation gives a slightly higher δ¹⁸O_w value compared to the previously estimated one, possibly as a result of lower body temperature. These data indicate that caution should be exercised when the relationship estimated for modern birds is applied to their basal counterparts that likely had a metabolism intermediate between that of their theropod dinosaur ancestors and that of advanced ornithurines.     

Occupational risk assessment in construction industry – Overview and reflection

The construction industry is plagued by occupational risky situations and poor working conditions. Occupational risk assessment (ORA) on workplace sites is the first and key step to achieve adequate safety levels, particularly to support decision-making in safety programs. Most construction safety efforts are applied informally under the premise that simply allocating more resources to safety management will improve safety on site. Moreover, there are many traditional methods to address ORA, but few have been adapted and validated for use in the construction industry, particularly in the design stage, for which traditional approaches do not give adequate answers. This paper presents a state-of-the-art on ORA traditional methods, for the construction industry, discussing their limitations and pointing advantages of using fuzzy sets approaches to deal with ill-defined situations.