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151.
This article explores similarities and differences between Internet-mediated climate change advocacy organizations and their legacy counterparts. It relies on a content analysis of advocacy emails produced by Environmental Defense Fund, Natural Resources Defense Council, Sierra Club, Greenpeace USA, League of Conservation Voters, Climate Reality Project, 1Sky, and 350.org. The study finds differences and similarities in strategic Internet use, including greater emphasis by climate groups on high threshold, offline actions; greater emphasis by legacy groups on low threshold, online actions; and high reliance by both framings that demand accountability from political elites. Implications for Internet-mediated and climate advocacy are discussed.  相似文献   
152.
Environmental Science and Pollution Research - In city playgrounds, there is a potential risk of harming children’s health by contamination coming from anthropogenic activities. With the aim...  相似文献   
153.

Social acceptance is fundamental, and directly affects the installation of wind farms. In this paper, the factors that have had the greatest influence on the development of wind energy in the Itsmo region of Tehuantepec, Mexico are identified. The data were collected face to face through a semi-structured questionnaire of 31 people: owners, municipal authorities, opposition groups, and academic members. The results of the interview highlight the social impact, the lack of application, and concerning ILO Convention 169, the abuse of community rights. As a result, people interviewed perceive that the environmental impact of the installation, and operation of wind farms has been ambivalent: positive due to the intrinsic benefits that wind energy generates compared to other energy sources, and negative in terms of affectation by the noise, and the landscape. However, the income received by the owners of land in which wind facilities are located is lower compared to other parts of the world. In general, the facts show a disintegration between the authorities (federal, state, and municipal), universities are isolated from wind projects, communities are not consulted in projects, and large companies are the main beneficiaries.

  相似文献   
154.
The paper applies the Contingent Valuation Method using a visitor survey to determine trip values to three rivers in northeastern Puerto Rico. Sample data were obtained from 984 interviews conducted in 13 sites during the summer months. The trip value is statistically decomposed into components representing natural features and recreation activities. The median net economic value of a river visit without waterfalls or foot trails is $96. Recreation at rivers with both waterfalls and foot trails has a median value of $138 per trip. The presence of waterfalls accounts for $23 and foot trails $19 per trip. This information can be pertinent for managers in selecting recreation site locations and protecting them from competing uses.  相似文献   
155.
Visitor use surveys and water quality data indicates that high visitor use levels of two rivers in Puerto Rico does not appear to adversely affect several water quality parameters. Optimum visitor use to maximize visitor defined satisfaction is a more constraining limit on visitor use than water quality. Our multiple regression analysis suggests that visitor use of about 150 visitors per day yields the highest level of visitor reported satisfaction, a level that does not appear to affect turbidity of the river. This high level of visitor use may be related to the gregarious nature of Puerto Ricans and their tolerance for crowding on this densely populated island. The daily peak visitation model indicates that regulating the number of parking spaces may be the most effective way to keep visitor use within the social carrying capacity.  相似文献   
156.
The Aguadulce aquifer unit in southeastern Spain is a complex hydrogeological system because of the varied lithology of the aquifer strata and the variability of the processes that can take place within the unit. Factorial analysis of the data allowed the number of variables to be reduced to 3 factors, which were found to be related to such physico-chemical processes as marine intrusion and leaching of saline deposits. Variographic analysis was applied to these factors, culminating in a study of spatial distribution using ordinary kriging. Mapping of the factors allowed rapid differentiation of some of the processes that affect the waters of the Gador carbonate aquifer within the Aguadulce unit, without the need to recur to purely hydrogeochemical techniques. The results indicate the existence of several factors related to salinity: marine intrusion, paleowaters, and/or leaching of marls and evaporitic deposits. The techniques employed are effective, and the results conform to those obtained using hydrogeochemical methods (vertical records of conductivity and temperature, ion ratios, and others). The findings of this study confirm that the application of such analytical methods can provide a useful assessment of factors affecting groundwater composition.  相似文献   
157.
Denitrification is applied in the tertiary treatment of wastewater to reduce nitrogen pollution. Fluorescence in situ hybridization (FISH), catalyzed reporter deposition (CARD)-FISH, cloning, and scanning electron microscopy (SEM) were applied to follow the evolution of the microbial composition and structure of granular sludge in chemolithotrophic denitrifying bioreactors fed with nitrate and thiosulfate. FISH oligonucleotide probes for the chemolitoautotrophic denitrifiers Thiobacillus denitrificans and Thiomicrospira denitrificans were designed and their utility tested. CARD-FISH and cloning data showed that bacterial diversity in the biofilms changed during the reactor operation. Chemoorganotrophic fermentative Gram-positive strains in the phyla, Actinobacteria and Firmicutes, were dominant in the methanogenic inoculum, both in terms of biodiversity and in number. Other significant phyla were Bacteroidetes and Chloroflexi. After 6 months of operation, Proteobacteria became dominant (83% of the clones). The diversity of Gram-positive bacteria was partially maintained although their abundance decreased notably. After 110 d of operation, the abundance of Tb. denitrificans cells increased considerably, from 1% to 35% of total DAPI-stained cells and from no isolated clones to 15% of the total clones. Tm. denitrificans only represented a minor fraction of the microorganisms in the sludge (1-4% of the DAPI-stained cells). These findings confirm that Tb. denitrificans was the dominant chemolitoautotrophic denitrifying microorganism in the bioreactors. The Archaeal diversity remained almost unchanged and it was represented mostly by Methanosaeta soehngenii. SEM results indicated a considerable loss in the integrity of the sludge granules during the operation, with risk of sludge buoyancy.  相似文献   
158.
The purpose of this investigation was to examine the proposition that creosote, emplaced in an initially water saturated porous system, can be removed from the system through Pickering emulsion formation. Pickering emulsions are dispersions of two immiscible fluids in which coalescence of the dispersed phase droplets is hindered by the presence of colloidal particles adsorbed at the interface between the two immiscible fluid phases. Particle trapping is strongly favoured when the wetting properties of the particles are intermediate between strong water wetting and strong oil wetting. In this investigation the necessary chemical conditions for the formation of physically stable creosote-in-water emulsions protected against coalescence by bentonite particles were examined. It was established that physically stable emulsions could be formed through the judicious addition of small amounts of sodium chloride and the surfactant cetyl-trimethylammonium bromide. The stability of the emulsions was initially established by visual inspection. However, experimental determinations of emulsion stability were also undertaken by use of oscillatory rheology. Measurements of the elastic and viscous responses to shear indicated that physically stable emulsions were obtained when the viscoelastic systems showed a predominantly elastic response to shearing. Once the conditions were established for the formation of physically stable emulsions a "proof-of-concept" chromatographic experiment was carried out which showed that creosote could be successfully removed from a saturated model porous system.  相似文献   
159.
The study of the ceramic characteristics of sludge ashes, alone or mixed with additives (kaolin, montmorillonite, illitic clay, powdered flat glass) includes characterization of additives, preparation of probes (dry or wet mixed), thermal treatment (up to 1200 degrees C, except melting or deformation) and control (densities, compressive strengths and water absorption). Thermal treatment increases the density and compressive strength of probes (both parameters go through maxima, with later decreases) and decreases the absorption of water. The densification is also revealed by the evolution of the ratio of decrease of volume/loss of mass. The maximum values of compressive strengths were obtained for 25% of illitic clay, montmorillonite and glass powder. Densification concerning probes with sludge ashes alone does not occur with kaolin. Experimental data were adjusted to exponential relationships between compressive strengths and densities for every composition, and also to a general equation for all probes. The apparent density obtained was adjusted to a non-linear dependence with temperature, leading to a maximum in density and permitting calculating the temperature of occurrence of this maximum. The adjustment was not possible for probes containing kaolin, requiring presumably higher temperatures to densify. Water absorption has low values for ashes or kaolin probes, intermediate values for illite and powdered flat glass probes and high values for montmorillonite probes. Excepting with kaolin, ceramic materials with better characteristics than sludge ashes without additives were obtained at lower treatment temperatures.  相似文献   
160.
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