Particulate matter levels in a South American megacity: the metropolitan area of Lima-Callao,Peru

The temporal and spatial trends in the variability of PM₁₀ and PM_2.5 from 2010 to 2015 in the metropolitan area of Lima-Callao, Peru, are studied and interpreted in this work. The mean annual concentrations of PM₁₀ and PM_2.5 have ranges (averages) of 133–45 μg m^?3 (84 μg m^?3) and 35–16 μg m^?3 (26 μg m^?3) for the monitoring sites under study. In general, the highest annual concentrations are observed in the eastern part of the city, which is a result of the pattern of persistent local winds entering from the coast in a south-southwest direction. Seasonal fluctuations in the particulate matter (PM) concentrations are observed; these can be explained by subsidence thermal inversion. There is also a daytime pattern that corresponds to the peak traffic of a total of 9 million trips a day. The PM_2.5 value is approximately 40% of the PM₁₀ value. This proportion can be explained by PM₁₀ re-suspension due to weather conditions. The long-term trends based on the Theil-Sen estimator reveal decreasing PM₁₀ concentrations on the order of ?4.3 and ?5.3% year^?1 at two stations. For the other stations, no significant trend is observed. The metropolitan area of Lima-Callao is ranked 12th and 16th in terms of PM₁₀ and PM_2.5, respectively, out of 39 megacities. The annual World Health Organization thresholds and national air quality standards are exceeded. A large fraction of the Lima population is exposed to PM concentrations that exceed protection thresholds. Hence, the development of pollution control and reduction measures is paramount.     

Towards a sustainable energy future—exploring current barriers and potential solutions in Thailand

Renewable energy is considered an indispensable basis of sustainable energy systems as electricity generation from renewable sources results in low emissions of greenhouse gases compared to fossil fuel based electricity and contributes to sustainable development. However, effective strategies and conducive institutional settings are needed for advancement of such clean electricity systems. Although Thailand, as a nation, has a huge potential for renewable energy utilization, its total amount of electricity generation from renewables is relatively small and could be enlarged substantially. Lack of policy mechanisms, institutional development and financing exist as major barriers for Thailand in this regard. Investigation of the nation’s current energy strategy implementation shows that relevant energy and development policies are at different stages of implementation and institutional settings are continuously evolving. This paper argues that further significant efforts could be made towards advancement of renewable electricity and thus achievement of energy sustainability in Thailand. Resource planning, effective policy and institutions, focussed planning for energy sustainability and implementation of the Clean Development Mechanism (CDM) under the Kyoto Protocol could facilitate further advancement of renewables for the nation.     

Spatial–temporal variability of epibenthic assemblages on subtidal biogenic reefs in the northern Adriatic Sea

Spatial distribution and temporal variation of epibenthic assemblages of coralligenous biogenic rocky outcrops occurring in the northern Adriatic Sea (45°04′–45°24′N; 12°23′–12°43′E) were investigated by photographic sampling from 2003 to 2006 at 12 randomly selected sites. The dominant reef-forming organisms were the encrusting calcareous algae (Lithophyllum stictaeforme, Lithothamnion minervae and Peyssonnelia polymorpha), while the main bioeroders were boring sponges (Cliona viridis, C. celata, C. thoosina, C. rhodensis, Piona vastifica) and the bivalve Gastrochaena dubia. Composition of the assemblages varied thorough years and among sites. Spatial heterogeneity, at local and regional scale, prevailed over temporal variation. This variability was related both to the geo-morphological features of the outcrops and to environmental variables. Sites clearly differed in the percent cover of reef builder and bioeroder species while only limited temporal variation within site was found. Some taxa revealed complex intra-site temporal trends. These results provide valuable information on the diversity and variability of epibenthic assemblages of the northern Adriatic coralligenous reefs, essential for the management and conservation of these unique biogenic habitats.     

Factors determining the hatching success of Antarctic krill <Emphasis Type="Italic">Euphausia superba</Emphasis> embryo: lipid and fatty acid composition

The present study addresses the effect of maternal diet on hatching success and condition of embryos and larvae of Antarctic krill Euphausia superba. Lipid and fatty acid content and composition were determined in field and laboratory samples. Developmental stages analyzed in embryos included: multiple-cell, gastrula, and limb-bud stages. Larval stages analyzed included: nauplius I, nauplius II, and metanauplius. Laboratory-reared embryos were spawned by gravid females incubated under three feeding groups: (1) phytoplankton mixture, (2) phytoplankton mixture and minced clam, and (3) phytoplankton mixture, minced clam, and commercial larval food. Hatching success was highest in group 3 (100%), lowest in group 1 (0%), and highly variable in field samples (0–48%). Lipid decreased slightly in embryos during embryonic development, while large decreases in lipid were found during nauplius development. High levels of 18:2(n-6), 20:4(n-6), and 22:6(n-3) observed with group 3 samples coincided with high hatching success in krill embryos. The ratio of 22:6(n-3)/20:5(n-3) also correlated to hatching success of embryos. The fatty acid profile of embryos in group 3 was similar to that of the field-collected embryos, reflecting the contribution of the commercial larval food in the maternal diet. In our study, the maternal diet was found to influence the fatty acid composition of embryos and in turn affects the hatching success of krill. Specific polyunsaturated fatty acids appeared to play important roles in embryogenesis in krill.     

Opportunities and challenges for mangrove carbon sequestration in the Mekong River Delta in Vietnam

Increasing value is attributed to mangroves due to their considerable capacity to sequester carbon, known as ‘blue carbon’. Assessments of opportunities and challenges associated with estimating the significance of carbon sequestered by mangroves need to consider a range of disciplinary perspectives, including the bio-physical science mangroves, social and economic issues of land use, local and international law, and the role of public and private finance. We undertook an interdisciplinary review based on available literature and fieldwork focused on parts of the Mekong River Delta (MRD). Preliminary estimates indicate mangrove biomass may be 70–150 t ha^?1, but considerably larger storage of carbon occurs in sediments beneath mangroves. These natural stores of carbon are compromised when mangroves are removed to accommodate anthropogenic activities. Mangroves are an important resource in the MRD that supplies multiple goods and services, and conservation or re-establishment of mangroves provides many benefits. International law and within-country environmental frameworks offer increasing scope to recognize the role that mangrove forests play through carbon sequestration, in order that these might lead to funding opportunities, both in public and private sectors. Such schemes need to have positive rather than negative impacts on the livelihoods of the many people living within and adjacent to these wetlands. Nevertheless, many challenges remain and it will require further targeted and coordinated scientific research, development of economic and social incentives to protect and restore mangroves, supportive law and policy mechanisms at global and national levels, and establishment of long-term financing for such endeavours.     

Lipid and protein utilisation during early development of yellowtail kingfish (<Emphasis Type="Italic">Seriola lalandi</Emphasis>)

The pelagic yellowtail kingfish Seriola lalandi has become a target species for aquaculture in Asia and Australasia. Australasian production is reliant on larviculture from eggs of captive brood stock; however, knowledge regarding the nutritional requirements of larvae of this species is still scarce, particularly in relation to lipids. As a first step in establishing these requirements, eggs and larvae from captive S. lalandi brood stock were examined for differences in total protein, total lipid and lipid classes between individual spawning events, over the spawning season, and during larval development from fertilisation to 15 days post hatch. Results indicate that total protein egg⁻¹ varied significantly between individual spawning events within a season, but neither total lipid nor total protein egg⁻¹ varied significantly across the spawning season. Brood stock egg lipids were made up of approximately 60% phospholipid, 25% wax and/or sterol esters (WE), 15% triacylglycerol (TAG), and small amounts of sterols and free fatty acids. During the early larval period, both WE and TAG were utilised concurrently for energy. The larvae experienced very high mortality around 5–7 days post hatch, which coincided with very low levels of all neutral lipid classes. Although many other factors may also influence larval mortality, these results indicate that lipid provisioning may be an important factor in larval survival during the critical period around first-feeding in this species. Examination of ratios of TAG:ST, often used as a condition index in fish larvae, suggested that some of the larvae were suffering from starvation. However, as egg-derived WE appears to provide a significant source of energy during the early larval period in S. lalandi, it is suggested that WE should be included in any index of larval nutritional state.     

Taxing Meat: Taking Responsibility for One’s Contribution to Antibiotic Resistance

Antibiotic use in animal farming is one of the main drivers of antibiotic resistance both in animals and in humans. In this paper we propose that one feasible and fair way to address this problem is to tax animal products obtained with the use of antibiotics. We argue that such tax is supported both by (a) deontological arguments, which are based on the duty individuals have to compensate society for the antibiotic resistance to which they are contributing through consumption of animal products obtained with the use of antibiotics; and (b) a cost-benefit analysis of taxing such animal products and of using revenue from the tax to fund alternatives to use of antibiotics in animal farming. Finally, we argue that such a tax would be fair because individuals who consume animal products obtained with the use of antibiotics can be held morally responsible, i.e. blameworthy, for their contribution to antibiotic resistance, in spite of the fact that each individual contribution is imperceptible.     

Determinants of Farmers’ Adoption of Improved Soil Conservation Technology in a Middle Mountain Watershed of Central Nepal

This study explores different socio-economic and institutional factors influencing the adoption of improved soil conservation technology (ISCT) on Bari land (Rainfed outward sloping terraces) in the Middle Mountain region of Central Nepal. Structured questionnaire survey and focus group discussion methods were applied to collect the necessary information from farm households. The logistic regression model predicted seven factors influencing the adoption of improved soil conservation technology in the study area including years of schooling of the household head, caste of the respondent, land holding size of the Bari land, cash crop vegetable farming, family member occupation in off farm sector, membership of the Conservation and Development Groups, and use of credit. The study showed that technology dissemination through multi-sectoral type community based local groups is a good option to enhance the adoption of improved soil conservation technology in the Middle Mountain farming systems in Nepal. Planners and policy makers should formulate appropriate policies and programs considering the farmers' interest, capacity, and limitation in promoting improved soil conservation technology for greater acceptance and adoption by the farmers.