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71.
Considering tobacco smoke as one of the most health-relevant indoor sources, the aim of this work was to further understand its negative impacts on human health. The specific objectives of this work were to evaluate the levels of particulate-bound PAHs in smoking and non-smoking homes and to assess the risks associated with inhalation exposure to these compounds. The developed work concerned the application of the toxicity equivalency factors approach (including the estimation of the lifetime lung cancer risks, WHO) and the methodology established by USEPA (considering three different age categories) to 18 PAHs detected in inhalable (PM10) and fine (PM2.5) particles at two homes. The total concentrations of 18 PAHs (ΣPAHs) was 17.1 and 16.6 ng m?3 in PM10 and PM2.5 at smoking home and 7.60 and 7.16 ng m?3 in PM10 and PM2.5 at non-smoking one. Compounds with five and six rings composed the majority of the particulate PAHs content (i.e., 73 and 78 % of ΣPAHs at the smoking and non-smoking home, respectively). Target carcinogenic risks exceeded USEPA health-based guideline at smoking home for 2 different age categories. Estimated values of lifetime lung cancer risks largely exceeded (68–200 times) the health-based guideline levels at both homes thus demonstrating that long-term exposure to PAHs at the respective levels would eventually cause risk of developing cancer. The high determined values of cancer risks in the absence of smoking were probably caused by contribution of PAHs from outdoor sources.  相似文献   
72.
Small farmers who supply the city of Bogotá with food are facing many challenges that are jeopardizing their livelihoods and by extension, the food security of Colombia’s capital. We expect future changes in climatic conditions to exacerbate the plight of the small farmers and this is expected to compromise Bogota’s food security even further. This paper specifically seeks to assess the impact of climate change (CC) on the livelihoods of smallholders who supply Bogota with most of its food. In our multidisciplinary methodology, we translated the exposure to CC into direct impact on crops and assessed sensitivity and adaptive capacity using the sustainable rural livelihoods framework. The results show that rainfall (by average of 100 mm) and temperature (by average of 2.1 °C) will increase over the study area, while the future climate suitability of the most important crops such as mango (Mangifera indica), papaya (Carica papaya), corn (Zea mays) and plantain (Musa balbisiana) shows a decrease of 19 % to 47 % climate suitability by the year 2050. The assessment of sensitivity and adaptive capacity demonstrates that farmers participating in a farmers’ market, initiated by several local and international non-governmental organizations (NGOs), are less vulnerable to CC than farmers who sell through intermediaries. Those farmers selling directly to consumers in the farmers’ market have a higher adaptive capacity (3 on a scale of 3) in social and financial capital than those selling to intermediaries with less adaptive capacity (1 on a scale of 3). In light of the reduction in overall climatic suitability of some of the major crops and the change of geographic location of suitability for others, there are likely to be serious threats for Bogotá’s food security, the ecological landscape around the city, and farmers’ livelihoods. We further conclude that unless proper adaptation measures are implemented, the geographical shift in climate suitability may also force farmers to shift their crops to higher elevations including remaining forests and páramos (the Colombian alpine tundra ecosystems), which may be threatened in the near future.  相似文献   
73.
The Watershed Flow and Allocation model (WaterFALL®) provides segment‐specific, daily streamflow at both gaged and ungaged locations to generate the hydrologic foundation for a variety of water resources management applications. The model is designed to apply across the spatially explicit and enhanced National Hydrography Dataset (NHDPlus) stream and catchment network. To facilitate modeling at the NHDPlus catchment scale, we use an intermediate‐level rainfall‐runoff model rather than a complex process‐based model. The hydrologic model within WaterFALL simulates rainfall‐runoff processes for each catchment within a watershed and routes streamflow between catchments, while accounting for withdrawals, discharges, and onstream reservoirs within the network. The model is therefore distributed among each NHDPlus catchment within the larger selected watershed. Input parameters including climate, land use, soils, and water withdrawals and discharges are georeferenced to each catchment. The WaterFALL system includes a centralized database and server‐based environment for storing all model code, input parameters, and results in a single instance for all simulations allowing for rapid comparison between multiple scenarios. We demonstrate and validate WaterFALL within North Carolina at a variety of scales using observed streamflows to inform quantitative and qualitative measures, including hydrologic flow metrics relevant to the study of ecological flow management decisions.  相似文献   
74.
In the present work, microalgae strains, such as Scenedesmus obliquus and Phaeodactylum tricornutum grown in indoor/outdoor photobioreactors (PBRs) and in open ponds (this is the first study on such strains cultivated in the local Southern Italy climatic conditions), were fully analyzed for their protein content, carbohydrates, lipids, and fatty acid profile in order to assess their potential use for the production of biofuels, chemicals, and omega-3, and as animal feed and human food. They are compared with Nannochloropsis sp. (commercial sample) which was fully analyzed in our laboratory and Chlorella (literature data). An economic evaluation was carried out, demonstrating that the cultivation of microalgae for the production of only biofuels will not match the economic standards. Conversely, if chemicals are also produced applying the biorefinery concept and using wastewater as a source of nutrients, it will be possible to have a good positive return from microalgae.  相似文献   
75.
Voluntary GHG management is a primary issue for many organizations. To support organizations with this activity, authoritative bodies have published many different guidelines. Nevertheless, these guidelines show limitations in identification of the direct and indirect processes that have a major impact on climate change, which should be considered in GHG management.In this paper, a life cycle approach is used to identify the processes of an organization and its supply chain that have major impacts on climate change. The results show that this approach is compatible with the current ISO standards and that in the case study the greatest emissions come from the organization’s indirect processes.  相似文献   
76.
Italy is a country highly vulnerable to floods and landslides. The present study aims to investigate disaster preparedness and perception of flood risk in a group of people living in an alpine valley in the north of Italy. Four hundred seven adult residents in nine communities exposed to hydrogeological risk were interviewed by using a structured questionnaire. Participants were asked about the adoption of a set of protective behaviors that can prevent negative consequences of floods. Perception of flood risk was assessed by means of a one-dimensional scale that was developed and validated by the authors. Items included in this scale asked participants to estimate likelihood of occurrence of different flood consequences and to express feelings of worry associated to them. Socio-demographic and experiential information on respondents were also collected. Overall, results showed that most of respondents were fairly well prepared to deal with a future flood disaster. Correlational and regression analyses indicated that disaster preparedness was positively associated with risk perception. In accordance with literature, there was not a significant relation between likelihood judgments and adoption of protective behaviors, while feelings of worry were associated with disaster preparedness. Authors interpret their results in relation to the socio-environmental characteristics of the studied communities. Theoretical, empirical and practical implications of the findings are also discussed.  相似文献   
77.
Mass balance to assess the efficiency of a mechanical-biological treatment   总被引:1,自引:0,他引:1  
Using mechanical-biological treatment of residual municipal solid waste, it is possible to significantly lower landfill volume and gas and leachate emissions. Moreover, the landfill characteristics are improved. The performance of the Mende (France) mechanical-biological treatment plant is assessed via mass balances coupled with manual sorting according to the MODECOMtrade mark methodology and biochemical methane potential after 90 days of incubation. The site includes mechanical sorting operations, a rotary sequential bioreactor, controlled aerobic stabilisation corridors, maturation platforms, and a sanitary landfill site for waste disposal in separated cells. Results showed that several steps could be improved: after a first sieving step, about 12% of the potentially biodegradable matter is landfilled directly without any treatment; mechanical disintegration of papers and cardboards in the rotary sequential bioreactor is insufficient and leads to a high proportion of papers and cardboards being landfilled without further treatment. Two fine fractions go through stabilisation and maturation steps. At the end of the maturation step, about 54% of the potentially biodegradable matter is degraded. The biochemical methane potential after 90 days of incubation is reduced by 81% for one of the two fine fractions and reduced by 88% for the other one. Considering the whole plant, there is a reduction of nearly 20% DM of the entering residual municipal solid waste.  相似文献   
78.
A bench-scale pilot plant has been developed for the treatment of olive-mill water. The plant is fed in a continuous mode and implements a primary treatment (sand filtering and irradiation with UV-rays) and a secondary treatment (anoxic and aerobic biological treatment). Satisfactory results were obtained and the treated green water falls under the limits of the Italian legislation. Veratric and ferulic acid biodegradation were studied under anoxic conditions in order to verify the requirements for optimal biodegradation. Electronic Publication  相似文献   
79.
ABSTRACT: Californian annual grassland on sandstone (moderately fertile) and serpentine (very infertile) soils at the Jasper Ridge Biological Preserve, Stanford, California, were exposed to ambient or elevated (ambient + 36 Pa CO2) atmospheric CO2 in open-top chambers since December 1991. We measured ecosystem evapotranspiration with open gas-exchange systems, and soil moisture with time-domain reflectometry (TDR) over 0–15 cm (serpentine) and 0–30 cm (sandstone) depths, at times of peak above ground physiological activity. Evapotranspiration decreased by 12 to 63 percent under elevated CO2 in three consecutive years in the sandstone ecosystem (p = 0.053, p = 0.162, p = 0.082 in 1992, 1993, and 1994, respectively). In correspondence with decreased evapotranspiration, late-season soil moisture reserves in the sandstone were extended temporally by 10 ± 3 days in 1993 and by 28 ± 11 days in 1994. The effect of elevated CO2 on soil moisture was greater in the drier spring of 1994 (419 mm annual rainfall) than in 1993 (905 mm annual rainfall). In the serpentine ecosystem, evapotranspiration and soil moisture reserves were not clearly affected by elevated CO2. Soil water may be conserved in drought-affected ecosystems exposed to elevated CO2, but the amount of conservation appears to depend on the relative importance of transpiration and soil evaporation in controlling water flux.  相似文献   
80.
Assessment of the pollution of water bodies from non-point sources is a complex data- and time-consuming task. The potential non-point pollution index (PNPI), is a new tool designed to assess the global pressure exerted on rivers and other surface water bodies by different land uses. The main feature of PNPI is the wide availability of its input data. Very detailed input maps, often lacking over many areas, are not needed for PNPI calculation. As a consequence of the input data used, the modelling of physical reality and of processes is heavily simplified. The authors counterbalanced such a simplification using an 'expert system' approach. The system bypasses the accurate representation of the physical reality to assess globally the pollution potential of different land uses according to the judgement of scientists. The scientific community proposes many models for depicting the dynamics of pollutants coming from diffuse sources. Most of them can be grouped into two broad categories: statistical models and physically based models. PNPI belongs to neither of the above-mentioned groups. PNPI is a GIS-based, watershed-scale tool designed to inform decision makers and public opinion about the potential environmental impacts of different land management scenarios. PNPI applies the multicriteria technique to pollutant dynamics and water quality. The pressure exerted on water bodies by diffuse pollution coming from land units is expressed as a function of three indicators: land use, run-off and distance from the river network. They are calculated from land use data, geological maps and a digital elevation model (DEM). The weights given to different land uses and to the three indicators were set according to experts' evaluations and allow calculation of the value of the PNPI for each node of a grid representing the watershed; the higher the PNPI of the cell, the greater the potential impact on the river network. The output of the calculation is presented in the form of maps that highlight areas that are more likely to produce pollution. Last, possibilities, strategies and results of the validation of the PNPI are described. In the authors' view, the explicit link between land use and potential pollution on which PNPI is based, together with its high communication potential, make it particularly interesting for a participatory and integrated approach to land management and environmental protection.  相似文献   
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