Impact of gold mining associated with mercury contamination in soil,biota sediments and tailings in Kenya

This work considered the environmental impact of artisanal mining gold activity in the Migori–Transmara area (Kenya). From artisanal gold mining, mercury is released to the environment, thus contributing to degradation of soil and water bodies. High mercury contents have been quantified in soil (140 μg kg^?1), sediment (430 μg kg^?1) and tailings (8,900 μg kg^?1), as expected. The results reveal that the mechanism for transporting mercury to the terrestrial ecosystem is associated with wet and dry depositions. Lichens and mosses, used as bioindicators of pollution, are related to the proximity to mining areas. The further the distance from mining areas, the lower the mercury levels. This study also provides risk maps to evaluate potential negative repercussions. We conclude that the Migori–Transmara region can be considered a strongly polluted area with high mercury contents. The technology used to extract gold throughout amalgamation processes causes a high degree of mercury pollution around this gold mining area. Thus, alternative gold extraction methods should be considered to reduce mercury levels that can be released to the environment.     

Comparative study of the urban quality of life in Cuban first-level cities from an objective dimension

The urban quality of life (UQoL) from objective dimension was analyzed in the main Cuban cities. An Urban Quality of Life Index (UQoLI) was developed in collaboration with 60 experts (five in each city). These experts belong to one of two categories: in charge of the planning of the city and members of the Municipal Council of Administration. One hundred and forty-two directors of the Local District Administration also participated in the analysis. The UQoLI includes three dimensions: social services, economic performance, and urban services, the importance of which is weighed according to expert criteria. A Ranking of the studied cities, sorted by the UQoLI, shows a tendency of increase it UQoL in the west even and central regions. This tendency contradicts one of the foundations of the Cuban sustainable development framework, i.e., equity.     

An assessment of the metabolic profile implied by agricultural change in two rural communities in the North of Argentina

The soy expansion model in Argentina generates structural changes in traditional lifestyles, which can be associated with different biophysical and socioeconomic impacts. To explore this issue, we apply an innovative method for integrated assessment—the multi-scale integrated analysis of societal and ecosystem metabolism framework—to characterize two communities in the Chaco Region, Province of Formosa, North of Argentina. These communities have recently experienced the expansion of soy production, altering their economic activity, energy consumption patterns, land use and human time allocation. The integrated characterization presented in the paper illustrates the differences (biophysical, socioeconomic and historical) between the two communities that can be associated with different responses. The analysis of the factors behind these differences has important policy implications for the sustainable development of local communities in the area.     

Perception of the effects of climate change in winter and summer tourist areas: the Pyrenees and the Catalan and Balearic coasts,Spain

In this study, we compare the perception of climate change in two different tourist settings of northeastern Spain: the Catalan Pyrenees and the Catalan Mediterranean coast and the Balearic Islands. We carried out a survey of 906 cases (506 in the coastal areas of Catalonia and the Balearic Islands and 400 in the Catalan Pyrenees) asking residents on those areas to assess the possible effects of climate change on tourist-related activities. While the existence of climate change and of its estimated impacts is widely accepted, we observe statistically significant differences in most of the questions between residents in the coastal areas and residents in the Pyrenees. In general terms, respondents from the Pyrenees display a much higher concern regarding the economic impacts of climate change on tourism. On the other hand, the results also show that some demographic groups, such as women, members of large households, or unemployed, tend to present higher levels of concern. This study may give new hints on which tourist modalities and which groups are more concerned for the impacts of climate change in Mediterranean tourist environments and could translate into more targeted adaptive and mitigation practices.     

Dispersing Bacterial Cellulose Nanowhiskers in Polylactides via Electrohydrodynamic Processing

In the present study, hybrid electrospun polylactide (PLA) fibers reinforced with highly dispersed crystalline bacterial cellulose nanowhiskers (BCNW) in solution concentrations up to 15 wt% were developed and characterized. The overall aim was to encapsulate dispersed BCNW in fibers to be later re-dispersed in virgin PLA by melt compounding. Initially, the suitability of three different solvents [1,1,1,3,3,3-hexafluoro-2-propanol (HFP), acetone–chloroform and chloroform/polyethylene glycol (PEG)] for fiber production was evaluated and solutions containing 5 wt% BCNW were used to generate electrospun hybrid PLA fibers. These fibers presented a homogeneous morphology, as assessed by scanning electron microscopy, and transmission electron microscopy images demonstrated that BCNW were well distributed along the fibers. Differential scanning calorimetry analyses showed that the incorporation of PEG into the fibers resulted in a T_g drop due to a plasticization effect and decreased thermal stability as a result of low interactions between the matrix and the BCNW. Subsequently, fibers were produced from the selected solutions (HFP and acetone–chloroform) containing up to 15 wt% BCNW. As a result of the great increase in the viscosity of the solutions, lower solids contents were required, leading to a better dispersion and incorporation degree of BCNW within the fibers. HFP was found to be a more suitable solvent, since higher incorporation levels were estimated by X-ray diffraction and improved matrix–filler interactions were suggested by a slight increase in the T_g of the fibers.     

Behaviour of oxyfluorfen in soils amended with edaphic biostimulants/biofertilizers obtained from sewage sludge and chicken feathers. Effects on soil biological properties

We studied the behaviour of oxyfluorfen herbicide at a rate of 4 l ha^?1 on biological properties of a Calcaric Regosol amended with two edaphic biostimulants/biofertilizers (SS, derived from sewage sludge; and CF, derived from chicken feathers). Oxyfluorfen was surface broadcast on 11 March 2013. Two days after application of oxyfluorfen to soil, both biostimulants/biofertilizers (BS) were also applied to the soil. An unamended soil without oxyfluorfen was used as control. For 2, 4, 7, 9, 20, 30, 60, 90 and 120 days of the application of herbicide to the soil and for each treatment, the soil dehydrogenase, urease, β-glucosidase and phosphatase activities were measured. For 2, 7, 30 and 120 days of the application of herbicide to the soil and for each treatment, soil microbial community was determined. The application of both BS to soil without the herbicide increased the enzymatic activities and soil biodiversity, mainly at 7 days of beginning the experiment. However, this stimulation was higher in the soil amended with SS than for CF. The application of herbicide in organic-amended soils decreased the inhibition of soil enzymatic activities and soil biodiversity. Possibly, the low-molecular-weight protein content easily assimilated by soil microorganisms is responsible for less inhibition of these soil biological properties.     

Agro-industrial wastes as effective amendments for ecotoxicity reduction and soil health improvement in aided phytostabilization

Aided phytostabilization is a technology that uses metal tolerant plants and organic and/or inorganic amendments to reduce soil metal bioavailability, while improving soil health. Our objective was to determine the effects of the application of amendments [sheep manure (SHEEP), poultry litter (POULTRY), cow slurry (COW), and paper mill sludge mixed with poultry litter (PAPER)], together with the growth of a metallicolous Festuca rubra L. population, on (i) chemical and microbial indicators of soil health and (ii) soil ecotoxicity, during the aided phytostabilization of a Zn/Pb contaminated mine soil. Amendment application led to an increase in soil pH, organic matter content, and inorganic salts, resulting in a decrease in Pb and Zn CaCl₂-extractable concentrations in soil, which, in turn, contributed to lower ecotoxicity and a stimulation of plant growth and soil microbial communities. The factor most affecting the metal extractability was probably soil pH. POULTRY was the best amendment in terms of increasing plant growth, chlorophylls content, and soil microbial biomass and activity, but resulted in higher levels of phytoavailable Pb and Zn. SHEEP and PAPER were more effective at reducing metal CaCl₂-extractability and, consequently, led to lower values of metal accumulation in plant tissues, thereby reducing the risk of metals entering into the food chain. When combined with the application of organic amendments, the metallicolous F. rubra population studied here appears an excellent candidate for aided phytostabilization. Our results indicate that the application of organic amendments is essential for the short-term recovery of highly contaminated metalliferous soils during aided phytostabilization.     

Testing instrumental and downscaled reanalysis time series for temperature trends in NE of Spain in the last century

In the context of climatic temperature studies, more often than not a time series is affected by artificial inhomogeneities. To overcome such limitation, we propose a new simple methodology in which promising results point not only toward the detection of unknown inhomogeneous periods but also toward the possibility of reconstructing the uncertain portion of the series. It is based on a parsimonious statistical downscaling (Multiple Linear Regression) of the large-scale 20CR reanalysis data. This method is successfully applied upon two long-range temperature series from a couple of centennial observatories (Ebre and Fabra, NE of Spain) which do not have nearby suitable temperature series to compare with. Results of trend analysis point to a clear signal of warming, with a larger rate of increase for the maximum temperature (respect to the minimum one), for the more recent decades (respect to the whole available period), and for the original series (respect to the reconstructed ones).     

Let’s play transformations! Performative methods for sustainability

Coping with global environmental change demands new forms of civic engagement and interaction able to transform passive audiences attending to the drama of unsustainability into committed actors for sustainability. This entails linking diverse sources of scientific knowledge with personal experiences, emotion and ethical judgments. In this paper, we assess the potential as well as the limitations of innovative theatre-based participatory tools and methods aimed at supporting sustainability learning and agent transformation. To this aim, we first review a series of experiences using theatrical performance and introduce the notion of performative methods. Second, we assess to what extent these new approaches can be of relevance in environmental action research and sustainability science, practice and learning. Finally, we list a series of key research questions to further guide methodological innovation in this promising area of sustainability science and practice. Our findings show a growing and successful use of such methodologies worldwide, both in academia and in implementation-oriented approaches. An increasing number of topics and complexity is being embraced by these methods, offering a fertile ground for innovation in participatory sustainability science.