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161.
根据2014年1月1日~6月30日江苏省13地级市监测PM2.5,PM10的数据,分析其污染特征.结果表明:全省PM2.5和PM10污染较严重,全省PM2.5,PM10超标率都分别达到78.33%,66.11%以上,尤其是细颗粒物的污染占主导地位;PM2.5/PM10的比值范围达到0.461 9~0.687 2,全省PM2.5和PM10之间存在显著的线性关系;PM2.5,PM10浓度时空分布特征为PM2.5:1月>3月>2月>5月>6月>4月,PM10:1月>5月>3月>6月>2月>4月;苏北>苏中>苏南.  相似文献   
162.
Governments, businesses, and lenders worldwide are adopting an objective of no net loss (NNL) of biodiversity that is often partly achieved through biodiversity offsetting within a hierarchy of mitigation actions. Offsets aim to balance residual losses of biodiversity caused by development in one location with commensurate gains at another. Although ecological challenges to achieve NNL are debated, the associated gains and losses for local stakeholders have received less attention. International best practice calls for offsets to make people no worse off than before implementation of the project, but there is a lack of clarity concerning how to achieve this with regard to people's use and nonuse values for biodiversity, especially given the inevitable trade-offs when compensating biodiversity losses with gains elsewhere. This is particularly challenging for countries where poor people depend on natural resources. Badly planned offsets can exacerbate poverty, and development and offset impacts can vary across spatial-temporal scales and by location, gender, and livelihood. We conceptualize the no-worse-off principle in the context of NNL of biodiversity, by exploring for whom and how the principle can be achieved. Changes in the spatial and temporal distribution of biodiversity-related social impacts of a development and its associated offset can lead to social inequity and negatively impact people's well-being. The level of aggregation (regional, village, interest group, household, and individual) at which these social impacts are measured and balanced can again exacerbate inequity in a system. We propose that a determination that people are no worse off, and preferably better off, after a development and biodiversity offset project than they were before the project should be based on the perceptions of project-affected people (assessed at an appropriate level of aggregation); that their well-being associated with biodiversity losses and gains should be at least as good as it was before the project; and that this level of well-being should be maintained throughout the project life cycle. Employing this principle could help ensure people are no worse off as a result of interventions to achieve biodiversity NNL.  相似文献   
163.
Emergencies resulting in large-scale displacement often lead to populations resettling in areas where basic health services and sanitation are unavailable. To plan relief-related activities quickly, rapid population size estimates are needed. The currently recommended Quadrat method estimates total population by extrapolating the average population size living in square blocks of known area to the total site surface. An alternative approach, the T-Square, provides a population estimate based on analysis of the spatial distribution of housing units taken throughout a site. We field tested both methods and validated the results against a census in Esturro Bairro, Beira, Mozambique. Compared to the census (population: 9,479), the T-Square yielded a better population estimate (9,523) than the Quadrat method (7,681; 95% confidence interval: 6,160-9,201), but was more difficult for field survey teams to implement. Although applicable only to similar sites, several general conclusions can be drawn for emergency planning.  相似文献   
164.
The chrome (Cr) is a metal utilized in various industrial sectors and its investigation in the environment is necessary, for the Cr (III) contain aessential micronutrients in the human nourishment and the Cr (VI), on the other hand, is toxic. In the present work soil contamination with Cr was realized in drainagelysimetersset in concentrations of 0, 200, 400, 600, 800 and 1000 mg kg−1 of total Cr, with the intuition to determine the total Cr and Cr (VI) flux in leached water, in soil and in plants of lettuce (Lactuca sativa L.). In the lysimeters were cultivated four plants, in three cultivation circles. In the end of the cultivations was observed, that the total applied Cr leached in the soil, evidencing the Cr mobility in latossoil with simulant characteristics to the ones utilized in this paper. The Cr (VI) concentrations in the soil increased soon after the treatment applications, but tend to decrees in the time elapse, the same tendences were observed for the total Cr concentrations in the leached water. The Cr absorption by plants was related to the Cr disponibility in the soil, for the soil concentration and the plants decreased with time passing. The Cr mobility in the soil possibilitated the groundwater contamination presenting risks to the water quality and, consequently to public health.  相似文献   
165.
In this study, we investigate association patterns of 249 bottlenose dolphin feeding groups off Sardinia Island (Italy) from January 2000–May 2007 and describe how their association behaviour is related to their response to food patches created by a marine fin fish farm. We also tested the hypothesis that dolphins have different social structures with different feeding activities: Associations should decrease during opportunistic feeding behaviours as it is easier to capture prey, and cooperation is not as necessary. Sixteen individually identified bottlenose dolphins were observed participating in both opportunistic and not opportunistic feeding activities, with a mean of 30 ± 8 times and 9.6 ± 1 times, respectively. Bottlenose dolphins show non-random social behaviour during feeding and this behaviour differs depending on their specific foraging activity. Dolphin associations during feeding can be divided into three categories: acquaintances, affiliates, and feeding associates. Association behaviour during fish farm feeding is consistent with our hypothesis that during opportunistic behaviours, benefits from cooperation decrease, as it is easier to capture prey. Group size homogeneity in both feeding activities demonstrates that the number of dolphins engaging in foraging is not necessarily related with cooperation levels. Moreover, an adult dolphin may prefer to associate with a specific individual, independent of the sex, who shares the same foraging priorities. This study is the first to show how aquaculture is not only directly affecting marine predators but could also indirectly affect their social structure and behaviour.  相似文献   
166.
Ambio - The chaotic distribution and dispersal of phosphorus (P) used in food systems (defined here as disorderly disruptions to the P cycle) is harming our environment beyond acceptable limits. An...  相似文献   
167.
Conservation science needs more high-quality impact evaluations, especially ones that explore mechanisms of success or failure. Randomized control trials (RCTs) provide particularly robust evidence of the effectiveness of interventions (although they have been criticized as reductionist and unable to provide insights into mechanisms), but there have been few such experiments investigating conservation at the landscape scale. We explored the impact of Watershared, an incentive-based conservation program in the Bolivian Andes, with one of the few RCTs of landscape-scale conservation in existence. There is strong interest in such incentive-based conservation approaches as some argue they can avoid negative social impacts sometimes associated with protected areas. We focused on social and environmental outcomes based on responses from a household survey in 129 communities randomly allocated to control or treatment (conducted both at the baseline in 2010 and repeated in 2015–2016). We controlled for incomplete program uptake by combining standard RCT analysis with matching methods and investigated mechanisms by exploring intermediate and ultimate outcomes according to the underlying theory of change. Previous analyses, focused on single biophysical outcomes, showed that over its first 5 years Watershared did not slow deforestation or improve water quality at the landscape scale. We found that Watershared influenced some outcomes measured using the survey, but the effects were complex, and some were unexpected. We thus demonstrated how RCTs can provide insights into the pathways of impact, as well as whether an intervention has impact. This paper, one of the first registered reports in conservation science, demonstrates how preregistration can help make complex research designs more transparent, avoid cherry picking, and reduce publication bias.  相似文献   
168.
Air quality can be affected by weather and thus is sensitive to a changing climate. Wildfire (influenced by weather), consecutive high temperature summer days, and other extreme events are projected to become more severe and frequent with climate change. These may create challenging conditions for managing air quality despite policy targets to reduce precursor and pollutant emissions. Although extreme events are becoming more intense and interest in climate adaptation is increasing among public health practitioners, little attention in scholarly literature and policy covers climate adaptation for air quality governance. Understanding the management and managers’ perspectives at the local level provides insight about the needs for climate adaptation, including their adaptation status, perspectives, responsibilities, and roles. This study explores local manager perspectives and experiences of managing air quality within a changing climate as one puzzle piece to understand the gap in climate adaptation within the air quality sector. A broader goal is to contribute to the discussion of developing a multi-jurisdictional vision for reducing the impacts of air quality in a changing climate. In 2016 local air quality district managers in California were invited to participate in an online survey of 39 questions focused on extreme event impacts on air quality. The questionnaire focused on present air quality threats and extreme event challenges, adaptation status and strategies, adaptive capacities, perceived barriers to adaptation, and jurisdictional responsibilities and roles. Over 85 percent of the 35 local air districts in California participated in the survey, which represents 80 percent of the state’s population. High awareness and knowledge of climate change among local managers indicates they are ready to adopt and take action on policies that would support climate adaptation, but barriers reported suggests they may need policies and adequate funding to take action and make necessary changes.

Implications: Downscaled global climate models project an increasing severity and frequency of extreme events. In the southwestern United States, these include wildfire, heat events, and dry periods, among others, all of which can place an extra burden on air quality managers and emitters to achieve air quality standards even as they reduce emissions. Despite climate change presenting increasing challenges to meet air quality standards, in the southwestern United States, policy and action to mitigate these impacts have been surprisingly absent. California presents a valuable case study on the topic because of its historic leadership in air quality management for the United States and also because of its initiatives in combating climate change. Yet still we found that adaptation has not been incorporated into air quality management thus far, but local managers seem sufficiently knowledgeable and willing.  相似文献   
169.
Inhaling particulate matter (PM) in environmental tobacco smoke (ETS) endangers the health of nonsmokers. Menthol, an additive in cigarettes, attenuates respiratory irritation of tobacco smoke. It reduces perceptibility of smoke and therefore passive smokers may inhale ETS unnoticed. To investigate a possible effect of menthol on PM concentrations (PM10, PM2.5, and PM1), ETS of four mentholated cigarette brands (Elixyr Menthol, Winston Menthol, Reyno Classic, and Pall Mall Menthol Blast) with varying menthol content was analyzed. ETS was generated in a standardized way using an automatic environmental tobacco smoke emitter (AETSE), followed by laser aerosol spectrometry. This analysis shows that the tested cigarette brands, despite having different menthol concentrations, do not show differences with regard to PM emissions, with the exception of Reyno Classic, which shows an increased emission, although the menthol level ranged in the midfield. More than 90% of the emitted particles had a size smaller than or equal to 1 µm. Regardless of the menthol level, the count median diameter (CMD) and the mass median diameter (MMD) were found to be 0.3 µm and 0.5 µm, respectively. These results point out that there is no effect of menthol on PM emission and that other additives might influence the increased PM emission of Reyno Classic.

Implications: Particulate matter (PM) in ETS endangers the health of nonsmokers and smokers. This study considers the effect of menthol, an additive in cigarettes, on PM emissions. Does menthol increase the amount of PM? Due to the exposure to secondhand smoke nearly 900,000 people die each year worldwide. The aim of the study is to measure the particle concentration (L?1), mass concentration (µg m?3), and dust mass fractions shown as PM10, PM2.5, and PM1 of five different cigarette brands, including four with different menthol concentrations and one menthol-free reference cigarette, in a well-established standardized system.  相似文献   
170.
Chitosan (CHS), chitosan–Eudragit® EPO (CHS–EPO) and chitosan beads partially cross-linked with glutaraldehyde (CHS–GLUT) were obtained in order to improve the adsorption selectivity of endoglucanase from a fungal culture obtained under SSF by Aspergillus niger using soybean harvest residues as support. The matrices synthetized were characterized in terms of physical and chemical changes. Fourier-transformed infrared spectroscopy with attenuated total reflectance device (FTIR-ATR) was employed to verify the chemical changes on the CHS matrix after the synthesis of CHS–GLUT and CHS–EPO. Scanning electron microscopy (SEM) was performed to compare the surface morphology of the polymeric beads. Two variables, purification factor and yield percentage of the adsorption process, were analyzed using a bifactorial ANOVA considering the matrix–time first order interaction. SEM results exhibited greater surface roughness in the CHS–GLUT and CHS–EPO matrices which may enhance endoglucanase adsorption. FTIR-ATR results confirmed an effective chemical modification of the CHS matrix after crosslinking with GLUT and corroborated the efficiency of the synthesis of the CHS–EPO matrix by the presence of chemical groups of the EPO polymer. An endoglucanase purification factor close to 9 was achieved with the CHS–GLUT matrix and a yield percentage of 60% was obtained with the CHS–EPO matrix. Bifactorial ANOVA results showed the matrix–time interaction to be significant for both variables. The CHS–GLUT matrix with low crosslinking times and the novel CHS–EPO matrix could be included in the bioseparation stage of endoglucanase using a simple and a low-cost method such as batch adsorption.  相似文献   
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