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931.
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. 相似文献
932.
Many ecotoxicological studies have addressed the effects of contaminant exposure at various levels of biological organization. However, little information exists on the effects of toxicants on wildlife populations. Here we examined exposure of populations of the greater white-toothed shrew Crocidura russula (Soricomorpha, Soricidae) occupying two protected Mediterranean sites (a polluted area, the Ebro Delta, and a control site, Garraf Massif). Bioaccumulation of selected elements (Pb, Hg, Cd, Zn, Cu, Fe, Mn, Cr, Mo, Sr, Ba, and B), a body condition index (BCI) and fluctuating asymmetry (FA) were used to assess the chronic exposure to environmental pollution. BCI was correlated neither to metal concentrations nor to FA, suggesting that this fitness measure only reflects environmental disturbances at a local level. However, shrews from the polluted area showed higher concentrations of metals and metalloids (Pb, Hg, B, and Sr) and greater shape FA than specimens from the reference area. A correlation between FA was found for both first and second principal component vectors suggesting that developmental instability increases as a result of exposure to multiple pollutants. Our results corroborate the suitability of C. russula as a bioindicator of environmental quality and show that FA is an appropriate index to examine impact of developmental stressors in populations inhabiting disturbed areas. 相似文献
933.
The present study evaluates the tolerance and accumulation potential of Vitis vinifera ssp. sylvestris under moderate and high external Cu levels. A greenhouse experiment was conducted in order to investigate the effects of a range of external Cu concentrations (0–23 mmol L−1) on growth and photosynthetic performance by measuring gas exchange, chlorophyll fluorescence parameters and photosynthetic pigments. We also measured the total copper, nitrogen, phosphorus, sulphur, calcium, magnesium, iron, potassium and sodium concentrations in the plant tissues. All the experimental plants survived even with external Cu concentrations as high as 23 mmol L−1 (1500 mg Cu L−1), although the excess of metal resulted in a biomass reduction of 35%. The effects of Cu on growth were linked to a reduction in net photosynthesis, which may be related to the effect of the high concentration of the metal on photosynthetic electron transport. V. vinifera ssp. sylvestris survived with leaf Cu concentrations as high as 80 mg kg−1 DW and growth parameters were unaffected by leaf tissue concentrations of 35 mg Cu kg−1 DW. The results of our study indicate that plants of V. vinifera ssp. sylvestris from the studied population are more tolerant to Cu than the commercial varieties of grapevine that have been studied in the literature, and could constitute a basis for the genetic improvement of Cu tolerance in grapevine. 相似文献
934.
935.
Air sparging (AS) was explored for remediation of a petroleum contaminated semi-confined groundwater system in NE China. Physical, hydro-chemical and hydraulic behaviors in subsurface environment during AS were investigated with support of modeling to understand the hydrogeo-chemical impacts of AS on the aquifer. The responses of groundwater, dissolved oxygen and temperature indicated that the radius of influence of AS was up to 8–9 m, and a 3D boundary of the zone of influence (ZOI) was accordingly obtained with volume of 362 m3. Water mounding unlike normal observations was featured by continuous up-lift and blocked dissipation. AS induced water displacement was calculated showing no obvious spreading of contaminant plume under this AS condition. Slug tests were employed before and after AS to reveal that the physical perturbation led to sharp increase in permeability and porosity. Modeling indicated that the regional groundwater flow field was not affected by AS except the physical perturbation in ZOI. Hydro-chemically increase of pH and Eh, and reduction of TDS, electrical conductivity and bicarbonate were observed in ZOI during AS. PHREEQC modeling inferred that these chemical phenomena were induced by the inorganic carbon transfer during air mixing. 相似文献
936.
This study reports a combined method using solid phase extraction (SPE), followed by solid phase microextraction (SPME) to concentrate different pesticides, including chlorinated, organophosphorus, triazines, pyretroids and chloroacetamides, present at trace levels in water samples. Identification and quantification was carried out by gas chromatography coupled to Mass Spectrometry (GC–MS). The optimized methodology showed LOQs at ng L?1 levels (ranging 0.2–3.5 ng L?1) in addition to acceptable precision and robustness (recoveries ranged 63–104%, RSD from 4% to 23%), presenting a novel method to reach trace levels, similar to that obtainable using EC detector, with structural confirmation by MS during the analysis of a wide range of environmental pollutants.This method was applied to the study of temporal and spatial distribution of pesticides in the Suquía River basin (Córdoba-Argentina). As expected, highest levels of agrochemicals were observed in areas with intensive agricultural practices, being atrazine (max. = 433.9 ng L?1), alpha-cypermetrine (max. = 121.7 ng L?1) and endosulfan sulfate (max. = 106.7 ng L?1) predominant. In urban areas, the prevalent pesticide was alpha-cypermethrine. These results draw attention to the need of pesticide monitoring programs in rivers, considering both urban and rural sections. 相似文献
937.
María Nazaret González-Alcaraz Héctor Miguel Conesa José Álvarez-Rogel 《Chemosphere》2013,90(10):2512-2519
The aim of this study was to assess the effectiveness of combining liming and vegetation for the phytomanagement of strongly acidic, saline eutrophic wetlands polluted by mine wastes. Simulated soil profiles were constructed and four treatments were assayed: without liming + without plant, without liming + with plant, with liming + without plant and with liming + with plant. The plant species was the halophyte Sarcocornia fruticosa. Three horizons were differentiated: A (never under water), C1 (alternating flooding–drying conditions) and C2 (always under water). The soluble Cd, Cu, Mn, Pb and Zn concentrations were measured regularly for 18 weeks and a sequential extraction procedure was applied at the end of the experiment. Liming was effective (between ~70% and ~100%) in reducing the soluble Zn, Cu and Pb. In contrast, soluble Mn and Cd increased with liming, especially in the treatment with liming + with plant, where the concentrations were 2-fold higher than in the non-limed treatments. The amendment increased the contents of Zn, Mn and Cd bound to potentially-mobilisable soil fractions at the expense of the most-environmentally-inert fractions. Hence, the combined use of liming and vegetation may increase the long-term environmental risk of metals solubilisation. 相似文献
938.
Daniel F. Valenzuela-Cota Génesis V. Buitimea-Cantúa Maribel Plascencia-Jatomea Francisco J. Cinco-Moroyoqui Aarón A. Martínez-Higuera 《Journal of environmental science and health. Part. B》2013,48(8):647-654
The aim of this study was to investigate the in vitro effect of an antifungal fraction obtained from Jacquinia macrocarpa plant (JmAF) in the generation of reactive oxygen species (ROS) and the activity of the catalase (CAT) and superoxide dismutase (SOD) enzymes from Fusarium verticillioides, as well as their influence in the viability of the fungus spores. The compounds present in the JmAF were determined by gas chromatography/quadrupole time-of-flight mass spectrometry (GC/QTOF-MS). The effect of the exposition to JmAF on the generation of ROS, as well as in the CAT and SOD activities in F. verticillioides, was determined. The main compounds detected were γ-sitosterol, stephamiersine, betulinol and oleic acid. JmAF showed very high ability in inhibiting the spore viability of F. verticillioides, and their capacity to cause oxidative stress by induction of ROS production. JmAF induced the highest ROS concentration and also inhibited CAT and SOD activities. The results obtained in this study indicate that JmAF is worthy of being considered for the fight against phytopathogenic fungi. 相似文献
939.
Ballesteros ML Bianchi GE Carranza M Bistoni MA 《Journal of environmental science and health. Part. B》2007,42(4):351-357
Toxicity tests using adult specimens of Jenynsia multidentata were carried out during 96 hours in order to determine the lethal concentration (LC50) of endosulfan. Histological alterations were determined in gills and liver. Gill damage was quantified as secondary lamellae thickness. The 96 hr LC50 values were significantly different between males (0.719 microg x L(-1)) and females (1.317 microg x L(-1)). The sex difference was attributed to the dimorphism in the lipid content in females (2.16%) and males (1.79%). Histological alterations in gills included hypertrophy and lifting of the epithelium of the secondary lamellae and aneurisms. These alterations caused a significant increase of the secondary lamellae thickness in treatment versus control fish. Finally, reversible histological alterations (such as hydropic degeneration and dilation of sinusoids) were observed in the liver of exposed fish as well as an irreversible change such as necrosis at the highest concentrations. 相似文献
940.
This paper introduces a new portable intelligent electronic nose system developed especially for measuring and analysing livestock
and poultry farm odours. It can be used in both laboratory and field. The sensor array of the proposed electronic nose consists
of 14 gas sensors, a humidity sensor, and a temperature sensor. The gas sensors were especially selected for the main compounds
from the livestock farm odours. An expert system called “Odour Expert” was developed to support researchers’ and farmers’
decision making on odour control strategies for livestock and poultry operations. “Odour Expert” utilises several advanced
artificial intelligence technologies tailored to livestock and poultry farm odours. It can provide more advanced odour analysis
than existing commercially available products. In addition, a rank of odour generation factors is provided, which refines
the focus of odour control research. Field experiments were conducted downwind from the barns on 14 livestock and poultry
farms. Experimental results show that the predicted odour strengths by the electronic nose yield higher consistency in comparison
to the perceived odour intensity by human panel. The “Odour Expert” is a useful tool for assisting farmers’ odour management
practises.
Supported by Ontario Pork, Natural Sciences and Engineering Research Council (NSERC), and Ontario Ministry of Agriculture
and Food (OMAF) of Canada. 相似文献