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321.
The aim of this work is the analysis of the dynamics in cultural landscapes, focused on the spatial distribution of changes in land cover and landscape patterns, and their possible linkages. These dynamics have been analyzed for the years 1957 and 2000 in a sector of the north of Galicia (NW Spain) characterized with diverse landscapes. Afforestation processes linked to agriculture abandonment and forestry specialization were the main processes observed in the study area, with the exception of the southern mountainous sector that was dominated by ploughing of scrubland for conversion into grassland, reflecting a specialization in livestock production. The structural changes that have taken place in most of the study area were related to the heterogeneity aspects, although the mountainous sectors were characterized by changes in heterogeneity and fragmentation. According to the tests performed, the comparison of the spatial distribution of both dynamics showed a certain statistical significance, reflecting the interrelationship between patterns and processes. This approach could be useful for the identification of areas with similar characteristics in terms of spatial dynamics so as to define more effective and targeted landscape planning and management strategies.  相似文献   
322.
The province of Siena, Italy, enacted a new garbage plan (NGP) with the objective of increasing separate waste collection (SWC), shutting down six landfills and increasing incineration. The aim of the paper is to evaluate costs and benefits of the NGP. The hypothesis is that willingness to pay (WTP) should reflect the value to the community of having better environmental quality, according to the Contingent Valuation literature. The paper reports the results of a contingent valuation (CV). The sample was divided into two subsets: firms and households. Through the information gathered via a detailed questionnaire, parametric and non-parametric estimates were elaborated to analyse the WTP of the population for the benefits flowing from increased SWC, increased incineration and shutting down of landfills. These values were expressed as a share of the tax actually paid. Although a small subset of firms and households valued increasing incineration less positively, requesting compensation, on the whole interviewees (with large differences between firms and households) had a net positive WTP for the provisions included in NGP. Parametric estimation procedures enabled us to analyse the economic as well as social and demographic factors affecting these results. These elements are useful for computing a value for the waste charge that also reflects external effects. Finally, we estimated household income elasticity of WTP for the increase in SWC and found less than one: environmental quality is not a luxury good.  相似文献   
323.
Atrazine (2-chloro-4-ethylamino-6-isopropylamino-s-triazine) was degraded using cobalt-peroximonosulfate (Co/PMS) advanced oxidation process (AOP). Three Co concentrations (0.00, 0.25 and 0.50 mM) and five peroximonosulfate (PMS) concentrations (0, 5, 8, 16 and 32 mM) were tested. Maximum degradation reached was 88% using dark Co/PMS in 126 minutes when 0.25 mM of cobalt and 32 mM of PMS were used. Complete atrazine degradation was achieved when the samples were irradiated by the sun under the same experimental conditions described. Tests for identification of intermediate products allowed identification and quantification of deethylatrazine in both dark and radiated conditions. Kinetic data for both processes was calculated fitting a pseudo-first order reaction rate approach to the experimental data. Having kinetic parameters enabled comparison between both conditions. It was found that the kinetic approach describes data behavior appropriately (R2 > or = 0.95). Pseudo-kinetic constants determined for both Co/PMS processes, show k value of 10(-4) for Co/PMS and a k value of 10(-3) for Co/PMS/ultraviolet (UV). This means, that, with the same Co/PMS concentrations, UV light increases the reaction rate by around one order of magnitude than performing the reaction under dark conditions.  相似文献   
324.
The effect of physical–chemical slurry treatment on the mobility and transformation of nitrogen and organic matter from pig slurry after soil application is evaluated. Two different pig slurries (one treated by stripping with air at pH = 9 and another non-treated) were applied at the top of a soil column, containing approximately 100 kg of soil. Effluents were monitored measuring concentration values of ammonia, nitrites, nitrates and total organic carbon (TOC). The breakthrough curves were modelled using STANMOD and HYDRUS 1D codes. Low concentrations of ammonia were detected in the effluent recovered at the bottom of the soil profile for both types of slurry. Nitrate concentration in effluent was lower and more homogenous over time when applying stripping treated pig slurry. In N modelling, adsorption of ammonia by soil proved an important process, nitrite and nitrate adsorption being less significant, although not negligible. Transformation from ammonia to nitrite controls the kinetics of the nitrification process. Total organic carbon in the column effluent was higher in the experiment using treated pig slurry, which can be attributed to organic matter solubilisation in the stripping treatment process.  相似文献   
325.
Aerobiological research into airborne pollen diversity and seasonal variations in pollen counts has become increasingly important over recent decades due to the growing incidence of asthma, rhinitis and other pollen-related allergic conditions. Airborne pollen in Guadalajara (Castilla-La Mancha, Spain) was studied over a 6-year period (2008–2013) using a Hirst-type volumetric spore trap. The highest pollen concentrations were recorded from February to June, coinciding with the pollen season of the pollen types that most contribute to the local airborne pollen spectrum: Cupressaceae (32.2 %), Quercus (15.1 %), Platanus (13.2 %), Olea (8.3 %), Populus (7.8 %) and Poaceae (7.2 %). These are therefore critical months for allergy sufferers. The pollen calendar was typically Mediterranean and comprised 25 pollen types. Between January and March, Cupressaceae pollen concentrations exceeded allergy risk thresholds on 38 days. Other woody species such as Olea and Platanus have a shorter pollen season, and airborne concentrations exceeded allergy risk thresholds on around 13 days in each case. Poaceae pollen concentrations attained allergy risk levels on 26 days between May and July. Other highly allergenic pollen types included Urticaceae and Chenopodiaceae-Amaranthaceae, though these are less abundant than other pollen types in Guadalajara and did not exceed risk thresholds on more than 3 and 5 days, respectively.  相似文献   
326.
At Seveso plants, duty holders must have a complex system for assessing and managing risks. The pillars of this system are the safety report and the safety management system, with a number of underlying documents. The strength of the system is the high standardization of these documents. Regulations, standard codes and guidelines define content, structure and formats. The weakness is the high complexity. Managers and workers perceive documents as difficult to understand and far from actual operations. Major threats for the credibility of documents (and therefore for the safety systems) come from the continuous organizational and technical changes, which in a short time can make most documents obsolete; as well as by near misses, which continuously show the holes in safety systems. A big effort is required to follow up the plant changes and the near misses. In order to help safety managers, a new software has been developed. At Seveso plants, it has been possible build an integrated digital representation, because all documents are perfectly structured. This representation may be used both for updating the relevant documents after a change and to improve documents after a near miss or an accident. In this way, safety documents are always up to date and trustworthy and the huge knowledge, which is usually hidden inside safety documents, is clearly revealed and revived. The approach is basically “knowledge based” and the intention is to provide safety managers with an easy and simple tool. IRISonLine is a software that has been developed by ISPESL to provide safety managers of “Seveso” establishments with a tool for improving the management of change and of near misses.  相似文献   
327.
Sulfonamides (SAs) have become one of the antibiotic families most frequently found in all kind of environmental waters. In the present work, the presence of 16 SAs and one of their acetylated metabolites in different water matrices of the Ebro River basin has been evaluated during two different sampling campaigns carried out in 2007 and 2008. Influent and effluent samples from seven wastewater treatment plants (WWTPs), together with a total of 28 river water samples were analyzed by on-line solid phase extraction-liquid chromathography-tandem mass spectrometry (on-line SPE-LC-MS/MS). Sulfamethoxazole and sulfapyridine were the SAs most frequently detected in WWTPs (96-100%), showing also the highest concentrations, ranging from 27.2 ng L(-1) to 596 ng L(-1) for sulfamethoxazole and from 3.7 ng L(-1) to 227 ng L(-1) for sulfapyridine. Sulfamethoxazole was also the SA most frequently detected in surface waters (85% of the samples) at concentrations between 11 ng L(-1) and 112 ng L(-1). In order to assess the effectiveness of the wastewater treatment in degrading SAs, removal efficiencies in the seven WWTPs were calculated for each individual SA (ranging from 4% to 100%) and correlated to the corresponding hydraulic retention times or residence times of the SAs in the plants. SAs half-lives were also estimated, ranging from to 2.5 hours (sulfadimethoxine) to 128 h (sulfamethazine). The contribution of the WWTPs to the presence of SAs depends on both the load of SAs discharging on the surface water from the WWTP effluent but also on the flow of the receiving waters in the discharge sites and the dilution exerted; WWTP4 exerts the highest pressure on the receiving water course. Finally, the potential environmental risk posed by SAs was evaluated calculating the hazard quotients (HQ) to different non-target organisms in effluent and river water. The degree of susceptibility resulted in algae>daphnia>fish. Sulfamethoxazole was the only SA posing a risk to algae in effluent water, with an HQ>7.  相似文献   
328.
Environmental Science and Pollution Research - Since COVID-19 pandemic, indoor air quality control has become a priority, and the development of air purification devices effective for disinfecting...  相似文献   
329.
Fire-retardant formulations are increasingly used by fire managers to control wildland fires. Their extensive use requires an assessment of their impacts in those ecosystems that could be affected by them. Recent studies indicate the potential for environmental impacts when accidentally delivered to surface waters. Yet the response of temporary wetlands, such as vernal pools, typical in Mediterranean areas, is unknown. This study reports on the emergence response of a wetland population of Daphnia curvirostris Eylmann (Cladocera, Crustacea) from sediments that were treated with a commercial fire retardant (Fire-Trol 934). Three application levels were used: 1, 3 and 5 L m(-2). The low and medium levels are in the range of manufacturer's recommendations of use in the field based on the fuel characteristics. The high level simulates local elevated concentrations that may result from inhomogeneous retardant delivery. Results indicate that emergence success decreases with increasing application rate, leading to a complete failure with application levels of 5 L m(-2). This suggests that benthic-pelagic interactions in temporary wetlands-often the primary way by which recolonization of isolated wetlands occurs-can be significantly impacted by fire retardants once they fill with fall/winter rains, thereby serving as a sensitive indicator of fire-retardant contamination. Results highlight a research need for establishing of criteria for effective, but environmentally safe use of fire retardants in the environment.  相似文献   
330.
Environmental Science and Pollution Research - Large amounts of residues generated by agricultural, urban and industrial activities are dumped daily on the soil. This practice deserves special...  相似文献   
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