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641.
The aim of this paper was to describe a new energy dependency score methodology and its consequent application to cars sold in twelve regions: Europe (EU-28) and eleven specific countries worldwide (Australia, Brazil, China, India, Japan, Norway, Portugal, Russia, Saudi Arabia, South Africa and USA). This methodology was developed as a potential tool to inform consumers of their choice impact on the country’s economy. This methodology is based on primary energy assessments and origins for each energy pathway associated with a gasoline-, diesel-, natural gas (used for H2 production)- or electricity (balanced with country electricity mix)-powered vehicle. An energy dependency index was attributed to the best-case (100 % endogenous production) and worst-case (0 % endogenous production) scenarios and consequently weighted with vehicle fuel consumption. This enabled obtaining an energy dependency index (10–0). This index could be assigned to an environmental and social index to provide a sustainability index and therefore complement a road vehicle environmental rating system, providing a combined index rating. Internal combustion engine vehicles and hybrid vehicles (that have oil products as energy source) rate the lowest for almost all locations, with the exception of regions that are energy independent (Norway, Saudi Arabia or Russia). Electric vehicles rank higher when comparing to the other technologies analyzed for all locations in this study. The plug-in hybrid electric vehicle shows generally a rank in an intermediate place, except for Japan where it scores lower than all other technologies.  相似文献   
642.
643.
Oil palm (Elaeis guineensis) has become one of the most rapidly expanding crops in the world. Many countries have promoted its cultivation as part of a broader rural development strategy aimed at generating paid work and producing both export commodities and biofuels. However, oil palm expansion has often occurred at the expense of ecosystems and subsistence agriculture, and on lands riddled with tenure conflicts. In this article, we analyse the implications of the combined effect of labouring in oil palm plantations and land access on households, and we discuss how these implications affect human well-being in two indigenous communities of the Polochic valley, Guatemala. Combining participant observation, semi-structured interviews, and land-time budget analysis at household level, we reveal how oil palm cultivation increases incomes for plantation workers’ households, but decreases the productivity of maize cultivation, reduces the time that household members have available for other activities and, particularly, reduces women’s resting time. In contrast, households that focus more intensively on maize cultivation show higher degrees of food security and women can allocate more time to social activities. However, our results also show that maize consumption per capita has not decreased in households working in oil palm plantations since such crop is considered sacred by the Q’eqchi’ and plays a central role in their diet and culture. In conclusion, we argue that while working for an oil palm cultivation can increase specific elements of the basic material conditions for a good life, other aspects such as food security, health, freedom of choice, and social relationships can become deteriorated.  相似文献   
644.
A field study was conducted in 2008 and 2009 at the USDA, ARS, Plant Genetic Resources Conservation Unit in Griffin, GA, to investigate weed suppression by sunn hemp (Crotalaria juncea L). The objectives were to (1) evaluate the effects of apical meristem removal (AMR) at three dates [5, 6, and 7 wks after planting (WAP) on May 14, 2008 and May 21, 2009] and (2) assess the impact of seeding rates (11, 28, and 45 kg ha?1) on weed biomass reduction. Weed species were identified at 4, 8, and 12 wks after sunn hemp planting. Sunn hemp cutting date had no significant effect on weed suppression in 2008 but significant differences for grass weeds at 4, 8, and 12 WAP and for yellow nutsedge at 8 and 12 WAP did occur when compared to the control in 2009. In comparison to the sunn hemp-free control plot in 2009, all three seeding rates had reduced grass weed dry weights at 4, 8, and 12 WAP. The total mass of yellow nutsedge when grown with sunn hemp was reduced compared to the total mass of yellow nutsedge grown in the weedy check for all seeding rates at 8 and 12 WAP. Lower grass weed biomass was observed by 12 WAP for cutting dates and seeding rates during 2008 and 2009. Sunn hemp cutting date and seeding rate reduced branch numbers in both years. The reduction in sunn hemp seeding rates revealed a decrease in weed populations.  相似文献   
645.
Outbreaks of bronchial asthma, defined by sharp peaks above the average number of emergency room visits at Charity Hospital in New Orleans, have been noted in this city since the early 1950’s. These outbreaks have occurred during the summer and fall, with the months of October and November containing the most frequent and severest episodes. Early work on this problem associated emissions from spontaneous underground burning in abandoned city dumps with the high incidence and extracts for skin testing prepared from the emissions produced a significant number of positive skin tests in persons involved in the asthma outbreaks. Recent investigation showed that other sources of allergenic air pollution in the city were related to the epidemics of asthma. Attention has been focused on a large public grain elevator at the Mississippi River in the southwestern portion of the city. Grain extracts have produced high percentages of positive responses in susceptible patients with low response rate found in control subjects. Persons known to have participated in these outbreaks have been characterized as being allergic; a low incidence of patients with chronic bronchitis and emphysema has been found in this group. New meteorological data regarding the outbreak periods has been collected.  相似文献   
646.
Biochar addition to soil is currently being investigated as a novel technology to remediate polluted sites. A critical consideration is the impact of biochar on the intrinsic microbial pollutant degradation, in particular at sites polluted with a mixture of readily biodegradable and more persistent organic pollutants. We therefore studied the impact of biochar (2% on dry weight basis) on the fate of volatile petroleum hydrocarbons in an aerobic sandy soil with batch and column studies. The soil-water partitioning coefficient, K(d), was enhanced in the biochar-amended soil up to a factor 36, and petroleum hydrocarbon vapor migration was retarded accordingly. Despite increased sorption, in particular of monoaromatic hydrocarbons, the overall microbial respiration was comparable in the biochar-amended and unamended soil. This was due to more rapid biodegradation of linear, cyclic and branched alkanes in the biochar amended soil. We concluded that the total petroleum hydrocarbon degradation rate was controlled by a factor other than substrate availability and the reduced availability of monoaromatic hydrocarbons in the biochar amended soil led to greater biodegradation of the other petroleum compounds.  相似文献   
647.
Larval dispersal connectivity is typically integrated into spatial conservation decisions at regional or national scales, but implementing agencies struggle with translating these methods to local scales. We used larval dispersal connectivity at regional (hundreds of kilometers) and local (tens of kilometers) scales to aid in design of networks of no-take reserves in Southeast Sulawesi, Indonesia. We used Marxan with Connectivity informed by biophysical larval dispersal models and remotely sensed coral reef habitat data to design marine reserve networks for 4 commercially important reef species across the region. We complemented regional spatial prioritization with decision trees that combined network-based connectivity metrics and habitat quality to design reserve boundaries locally. Decision trees were used in consensus-based workshops with stakeholders to qualitatively assess site desirability, and Marxan was used to identify areas for subsequent network expansion. Priority areas for protection and expected benefits differed among species, with little overlap in reserve network solutions. Because reef quality varied considerably across reefs, we suggest reef degradation must inform the interpretation of larval dispersal patterns and the conservation benefits achievable from protecting reefs. Our methods can be readily applied by conservation practitioners, in this region and elsewhere, to integrate connectivity data across multiple spatial scales.  相似文献   
648.
Human relationships with trees can result in widespread citizen-led reforestation projects that catalyze social–biological-reinforcing feedback loops and set in motion virtuous cycles that restore perturbed social–ecological systems. These virtuous cycles confer resilience in such systems that counterbalance the tendency for vicious cycles to be triggered by destructive behavior and neglect. Given this argument, we ask: how do we cultivate the potential for virtuous cycles to confer resilience in social–ecological systems? To answer this question, we review feedback mechanisms and identify virtuous cycles catalyzed via ecological restoration to highlight their importance to the resilience of social–ecological systems. We then conceptualize these cycles with a causal map (also known as a causal loop diagram) illustrating an example where restoration activities and civic ecology practices contributed to feedbacks and virtuous cycles. Following from this example, we discuss approaches for recognizing and investing in virtuous cycles that accompany social–ecological systems and outline approaches for managing such cycles.  相似文献   
649.
The motorcycle taxi drivers of Bangkok have been heavily exposed to high concentrations of PM10 (particulate matter with an aerodynamic diameter ≤10 μm), and the impact of this on their lungs has been neither documented nor studied. This study examines the association between exposure to PM10 and lung function decline among motorcycle taxi drivers. A cross-sectional study was conducted in Bangkok between two groups: a subject group of motorcycle taxi drivers and control group of enclosed vehicle taxi drivers. The findings of the Thailand Pollution Control Department were used to estimate the annual ambient PM10 concentration levels in the metropolis. Pulmonary functions of motorcycle taxi drivers and enclosed vehicle taxi drivers were measured and compared using the Mann-Whitney test. Multiple linear regression analysis was applied to estimate the effects of PM10 exposure on the lung function of motorcycle taxi drivers. A total of 1283 motorcycle taxi drivers and 600 taxi drivers were investigated. The mean forced expiratory volume in 1 sec/forced vital capacity (FEV1/FVC) of the motorcycle taxi drivers was significantly lower than that of the taxi drivers (P < 0.001). The mean FEV1/FVC of motorcycle taxi drivers exposed to ≥50 µg/m3 PM10 was statistically lower (?2.82%; 95% confidence interval [CI]: ?4.54% to ?1.09%) and the mean % vital capacity (%VC) of those exposed to 40–49.9 µg/m3 PM10 was statistically lower than that of motorcycle taxi drivers exposed to <30 µg/m3 PM10 (?3.33%; 95% CI: ?5.79% to ?0.87%). Motorcycle taxi drivers were directly exposed to air pollution in their working environment. As a result, their lung function might decrease more than that of enclosed vehicle taxi drivers. With the possible exposure to ≥50 µg/m3 PM10, the vehicular emission standards should be vigorously enforced. Further investigation is warranted to clarify the effect of lung dysfunction on the work and lifestyle of motorcycle taxi drivers.

Implications: Motorcycle taxi drivers are directly exposed to air pollution in their work environment; therefore, their lung function might decrease more than that of enclosed vehicle taxi drivers, especially when exposed to ≥50 µg/m3 PM10. World Health Organization (WHO) vehicular emission standards should be recognized and eventually enforced.  相似文献   
650.
One of the challenges faced by waste management authorities is determining the amount of waste generated by households in order to establish waste management systems, as well as trying to charge rates compatible with the principle applied worldwide, and design a fair payment system for households according to the amount of residential solid waste (RSW) they generate. The goal of this research work was to establish mathematical models that correlate the generation of RSW per capita to the following variables: education, income per household, and number of residents. This work was based on data from a study on generation, quantification and composition of residential waste in a Mexican city in three stages. In order to define prediction models, five variables were identified and included in the model. For each waste sampling stage a different mathematical model was developed, in order to find the model that showed the best linear relation to predict residential solid waste generation. Later on, models to explore the combination of included variables and select those which showed a higher R(2) were established. The tests applied were normality, multicolinearity and heteroskedasticity. Another model, formulated with four variables, was generated and the Durban-Watson test was applied to it. Finally, a general mathematical model is proposed to predict residential waste generation, which accounts for 51% of the total.  相似文献   
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