The PAF model: an integrated approach for landfill sustainability

Lab-scale tests were set up to investigate different options for achieving sustainability by reducing long-term landfill emissions. The options which have been studied and compared with the traditional anaerobic landfill for unprocessed refuse were: mechanical-biological pretreatment, landfill aeration with forced and with natural advective air flow (semi-aerobic), flushing. Combination of different options have been experimented. The combination of mechanical-biological Pretreatment, Aeration by the semi-aerobic method and Flushing (PAF model) seems to synergize the advantages of the individual options. The research is ongoing and further studies are necessary in order to assess the full-scale applicability of the model.     

In situ bioremediation of a hydrocarbon polluted site with cyclodextrin as a coadjuvant to increase bioavailability

Bioavailability is one main factor that influences the extent of biodegradation of hydrocarbons. They are very poorly soluble in water and easily adsorbed to clay or humus fractions, so they pass very slowly to the aqueous phase where they are metabolised by microorganisms. Cyclodextrins are natural compounds that form soluble inclusion complexes with hydrophobic molecules and increase degradation rate of hydrocarbons in vitro. In the perspective of an in situ application, we previously checked that -cyclodextrin does not increase eluviation of hydrocarbons through the soil and consequently does not increase the risk of groundwater pollution. The results of an in situ application of -cyclodextrin for bioremediation of a hydrocarbon polluted site are presented. We stated that the combination of bioaugmentation and enhanced bioavailability due to -cyclodextrin was effective for a full degradation.     

Microbial response to heavy metal-polluted soils: community analysis from phospholipid-linked fatty acids and ester-linked fatty acids extracts

Heavy metal pollution of soil is of concern for human health and ecosystem function. The soil microbial community should be a sensitive indicator of metal contamination effects on bioavailability and biogeochemical processes. Simple methods are needed to determine the degree of in situ pollution and effectiveness of remediating metal-contaminated soils. Currently, phospholipid-linked fatty acids (PLFAs) are preferred for microbial profiling but this method is time consuming, whereas direct soil extraction and transesterification of total ester-linked fatty acids (ELFAs) is attractive because of its simplicity. The 1998 mining acid-metal spill of >4000 ha in the Guadiamar watershed (southwestern Spain) provided a unique opportunity to study these two microbial lipid profiling methods. Replicated treatments were set up as nonpolluted, heavy metal polluted and reclaimed, and polluted soils. Inferences from whole community-diversity analysis and correlations of individual fatty acids with metals suggested Cu, Cd, and Zn were the most important in affecting microbial community structure, along with pH. The microbial stress marker, monounsaturated fatty acids, was significantly lower for reclaimed and polluted soil over nonpolluted soils for both PLFA and ELFA extraction. Another stress marker, the monounsaturated to saturated fatty acids ratio, only showed this for the PLFA. The general fungal marker (18:2omega6c), the arbuscule mycorrhizae marker (16:1omega5c), and iso- and anteiso-branched PLFAs (gram positive bacteria) were suppressed with increasing pollution whereas 17:0cy (gram negative bacteria) increased with metal pollution. For both extraction methods, richness and diversity were greater in nonpolluted soils and lowest in polluted soils. The ELFA method was sensitive for reflecting metal pollution on microbial communities and could be suitable for routine use in ecological monitoring and risk assessment programs because of its simplicity and reproducibility.     

Soil erosion under different vegetation covers in the Venezuelan Andes

This comparative study of soil erosion considered different environments in an ecological unit of the Venezuelan Andes. The soils belong to an association of typic palehumults and humic dystrudepts. Soil losses were quantified by using erosion plots in areas covered by four types of vegetation, including both natural and cultivated environments. The highest soil erosion rate evaluated corresponded to horticultural crops in rotation: reaching a value of 22 Mg ha^–1 per year. For apple tree (Malus sylvestris Miller) plots, soil losses reached values of 1.96 Mg ha^–1 per year. Losses from pasture (Pennisetum clandestinum Hochst. ex Chiov.) plots, without livestock grazing, were as high as 1.11 Mg ha^–1 during the second year of the experiment. The highest soil losses generated from plots under natural forest were equal to 0.54 Mg ha^–1 per year. Environmental factors such as total and effective rainfall, runoff, and some soil characteristics as those related to soil losses by water erosion were evaluated. The type of management applied to each site under different land use type and the absence of conservation practices explain, to a large extent, the erosive processes and mechanisms.     

Managing natural resources in the light of climate variability

Natural resource management is central to global efforts to reduce poverty and environmental degradation, and is one of the principal ways in which countries are seeking to advance sustainable development and the implementation of Agenda 21. But these efforts to advance natural resource management are strongly impacted by climate and by seasonal and inter–annual climate variability.
This article aims to further advance understanding of the relationship between natural resource management and climate variability, with particular attention to ways in which natural resource managers at every level — from the household to the national and international levels — can cope more effectively with such variability. In particular, the article provides an overview of the way in which efforts to manage natural resources to reduce poverty and environmental degradation are impacted by natural climate variability. It examines what natural resource managers are doing to cope with these challenges, and discusses the kinds of new approaches and partnerships that are needed to improve their capacity to cope more effectively with climate variability. In doing so, the article touches on the implications of future climate changes for natural resource managers and the way in which their efforts to cope more effectively with climate variability will provide opportunities to gain experience in identifying and adjusting responses to longer–term climate change.     

Climate change-induced salinity variation impacts on a stenoecious mangrove species in the Indian Sundarbans

The alterations in the salinity profile are an indirect, but potentially sensitive, indicator for detecting changes in precipitation, evaporation, river run-off, glacier retreat, and ice melt. These changes have a high impact on the growth of coastal plant species, such as mangroves. Here, we present estimates of the variability of salinity and the biomass of a stenoecious mangrove species (Heritiera fomes, commonly referred to as Sundari) in the aquatic subsystem of the lower Gangetic delta based on a dataset from 2004 to 2015. We highlight the impact of salinity alteration on the change in aboveground biomass of this endangered species that, due to different salinity profile in the western and central sectors of the lower Gangetic plain, shows an increase only in the former sector, where the salinity is dropping and low growth in the latter, where the salinity is increasing.     

Biomass from phytopathogens and culture conditions improve Penicillium chrysogenum antimicrobial activity and antifungal compounds production

The present study evaluated the effect of culture conditions and phytopathogenic strain co-culture on the production of antimicrobial metabolites and antifungal activity of Penicillium chrysogenum R1, which PCR identified. Antimicrobial activity was determined using the Hunter-Hunter experimental design with three factors (pH, incubation temperature, and inoculum, at two levels each). The antifungal metabolites, β 1-3 glucanase and chitinase, produced in the presence of live and inactivated Fusarium oxysporum Fsox C11 biomass, were evaluated using HPLC-MS and GC-MS. Results showed that P. chrysogenum inhibited the growth of five phytopathogenic fungal strains, and the most significant inhibition was observed for F. oxysporum Fsox C11. The best conditions to achieve the highest antifungal activity of the cell-free extract were pH 7, 28°C, 1 × 10⁶ spores/mL, and 144 h of fermentation, observing 86% inhibition of F. oxysporum Fsox C11 growth. Production of antifungal metabolites such as 1,4-benzoquinone imine, viridicatic acid, phenol-5-methyl-2-(1-methyl ethyl), and hydrolytic enzymes β 1-3 glucanase and chitinase was detected. The results define the perspective in designing new processes and products for biocontrol phytopathogens.     

Perceptions of industrial risk and emergency management procedures in Hazmat Logistics: A qualitative mental model approach

In the industrial risk field, Hazmat Logistics research is growing as a sector of special relevance. The road transport of these substances is an activity with an elevated risk, involving drivers, logistics systems, industries, infrastructures, urban areas, etc.In the study of risk and safety of the logistics of hazardous materials there is a special relevance for new and complex elements, as human factors and mental models involved in managing critical incidents ‘‘on the road”. Moreover, the ‘‘emergency management training” of human resources in this field is often limited, and this represents another factor of vulnerability.In collaboration with SBG (one of the leading European Hazmat Logistics corporations), we developed a quali-quantitative study on cognitive representations and semantic perceptions of risk and emergency management procedures in tanker drivers. The main innovation of the study, with the direct involvement of the stakeholder and 47 drivers, is represented by the construction and use of ‘‘ad hoc” psychometrical and knowledge-elicitation, allowing a deeper analysis of workers’ mental models.The application of PCP tools of adapted RepGrid and Landfield Laddering Procedures allows to analyze some of the main qualitative structures of mental models held by drivers about Hazmat Logistics. Through the analysis of these mental models, it could become possible to set up efficient preventive actions for this type of industrial risk. We are going to discuss the consequences of these findings and methodological approaches for the industrial risk-and-safety field.     

Bags with oven-dried moss for the active monitoring of airborne trace elements in urban areas

To define a harmonized methodology for the use of moss and lichen bags as active monitoring devices of airborne trace elements in urban areas, we evaluated the element accumulation in bags exposed in Naples in different spring weather conditions for 6- and 12-weeks. Three different pre-exposure treatments were applied to moss and lichen materials: water-washing, acid-washing and oven-drying. During the different exposure periods in the Naples urban environment the moss accumulated always higher amounts of elements (except Hg) than lichens and the element accumulation increased during wetter weather and higher PM₁₀ conditions. The oven pre-treatment did not substantially modify the morphology and element composition of moss and the exposure in bags of this material for 6-weeks was sufficient to detect the pattern of airborne trace elements.