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1.
The sharing of environmental cost by residents in various residential areas in the developing world is perceived to be unfair. This study therefore assessed residents’ experiences of environmental justice in Ile-Ife, Nigeria. Three residential areas were identified in the study area and samples were selected using systematic sampling. Using availability and condition of urban infrastructure, severity of environmental problems and residents’ involvement in environmental issues, the study examined environmental justice in the study area. The study established a variation in environmental issues across identified residential areas. The severity of environmental problem measured through an index tagged Severity of Environmental Problem (SEPI) revealed that environmental problems was most severe in the core (SEPI = 4.00), followed by the peripheral area (SEPI = 3.71) and least in the transition area (SEPI = 3.56). On the condition of available environmental infrastructure, the study revealed that the conditions of infrastructure were most improved in the peripheral area (ICI = 3.07), followed by the core (ICI = 2.67) and the least in the transition area (ICI = 2.42). The study concluded that residents’ experiences of environmental justice differ significantly across the different residential zones as reflected by residents’ socio-economic characteristics. Furthermore, it established that age, gender, educational status, and number of years spent in the area can be used to explain the differences in residents’ experience of environmental justice in the study area. To enhance the liveability, the study recommends adequate provision of environmental amenities needed by each category of people in the city.  相似文献   
2.
Air pollution is one of the primary concerns of our society for its effect on human health and the environment. Among the policy measures that can be put in place to limit air pollutant emissions, end-of-pipe technologies and/or regulatory instruments may be implemented through legislative acts. Also, equally important are behavioural measures, requiring citizens’ active involvement. The success of any measure to limit pollutant emissions requires the acceptance by the citizens that, in turn, implies a correct perception of the main pollutant emission drivers. We present here the comparison between the public perception of air pollution sources and the real-world situation through a survey carried out in seven European countries and involving 16 101 respondents. Our study shows a dramatic underestimation of the contribution of the agri-food sector to air pollution. This result is common to all respondents in the seven countries examined and only to a small extent depends on gender, age and socio-economic status of the respondents.  相似文献   
3.
This article postulates strong endogenous relationships in lower income countries between institutional quality, financial development and sustained economic growth. These associations were investigated using the vector-error correction model (VECM) and Granger causality method for a sample of 79 countries from 2005 to 2022. The findings show that (1) these variables reinforce each other in the short run. (2) In the long run, both institutional quality and financial development can fuel economic growth. (3) The positive effect of institutional quality on economic growth is greater than that of financial development. Policy implications of these findings are that careful attention should be paid to co-development policies to enhance the institutional quality and the financial system in these economies. Policies should also consider economic growth strategies to enable sustainable economic growth rates.  相似文献   
4.
In this laboratory study different combinations of bed (sand, pebble gravel [gravel], and a mix of sand and gravel) and flow (typical and overtopping) were experimented with to investigate the impact of porous deflectors in flow diversity, water quality, and fish performance in prismatic open channels. Deflectors changed the gradually varied flow to a rapidly varied flow, as a sudden change in the water depth was observed at the deflectors, and this change was large for smooth beds. With the presence of gravel, the scouring near the downstream deflector was almost twice that of the sand bed, and with the scouring at its own upstream deflector, irrespective of whether the flow was typical or overtopping. This behavior was a result of sand mobilization due to shear stress and sand mobilization aided gravel transport. The mixed bed showed less gravel movement compared to the gravel-only bed. The percentage of sediment washed out was minor for all bed scenarios, indicating that sediment transport was local. Relative to the sand bed without deflectors (representing a typical urban canal), deflectors resulted in reduced and improved water quality (in terms of sediment load) for sand, and mixed bed, respectively. The fishes found refuge and were comfortable in the pool areas created by deflectors unlike in channels without deflectors where they showed exhaustion.  相似文献   
5.
The High Plains aquifer (HPA) is the primary water source for agricultural irrigation in the US Great Plains. The water levels in many locations of the aquifer have declined steadily over the past several decades because the rate of water withdrawals exceeds recharge, which has been a serious concern to the water resources management in the region. We evaluated temporal trends and variations in agricultural water use and hydroclimatic variables including precipitation, air temperature, reference evapotranspiration, runoff, groundwater level, and terrestrial water storage across the HPA region for different periods from 1985 to 2020 at the grid, county, or region scale. The results showed that water withdrawals decreased from 21.3 km3/year in 1985 to 18.2 km3/year in 2015, while irrigated croplands increased from 71,928 km2 in 1985 to 78,464 km2 in 2015 in the entire HPA. The hydroclimatic time-series showed wetting trends in most of the northern HPA, but drying and warming trends in the southern region from 1985 to 2020. The groundwater level time-series indicated flat trends in the north, but significant declining in the central and southern HPA. Trends in irrigation water withdrawals and irrigation area across the HPA were controlled by the advancement of irrigation systems and technologies and the management of sustainable water use, but also were affected by dynamical changes in the hydroclimatic conditions.  相似文献   
6.
根据长三角空气质量区域预报工作的实际需要,对分区文字预报和落区图预报两种方式分别制定了不同的空气质量指数级别预报准确性评估方法。分区文字预报根据设定的预报准确性判定方法计算预报评分,落区图预报按区域内预报准确城市占比进行准确率统计。分区文字预报结果显示,2017年长三角区域的预报准确天数占比为62.2%,预报评分为70.2,区域预报评估效果良好。落区图预报评估结果显示,预报级别偏差具有地域性差异,安徽北部、江苏北部和江西中北部预报等级偏高,长三角中南部沿海城市预报等级偏低。该套评估方法可为区域空气质量预报偏差成因分析提供依据,为区域预报工作的改进提供定量参考。  相似文献   
7.
为了解决吸附速率拟合公式缺乏而解吸经验公式众多的问题,通过替换解吸参数、定性和对比分析各经验公式对煤吸附CO2,N2,CH4吸附速率的适用性,选取4种不同煤质的煤样在0.5,1.0和2.0 MPa下进行定温吸附实验,分析压力和煤质对吸附速率的影响规律。研究结果表明:时间函数式对3种气体在不同压力和煤质下的吸附速率拟合效果最佳;压力和煤质对3种气体吸附速率的影响既存在共性又具有差异性,气体吸附速率与压力符合指数函数关系,与挥发分呈现出二次函数关系,并且压力升高会导致最低吸附速率趋向于较高变质程度煤样;CH4和N2的吸附速率随压力升高而升高,而CO2的吸附速率因煤样而不同,且在同压下,不同气体的最高和最低吸附速率煤样的变质程度也不同。  相似文献   
8.
随着浙江"五水共治"工作的深化,宁波作为浙江"五水共治"的中坚力量,始终把"五水共治"作为全市工作的首要任务和突破重点。自1999年进行清淤后,月湖水质得到短期改善,然而治标不治本的治理措施,并没有让月湖水质得到根本改善。因此,对月湖进行科学有效的生态修复,针对性地处理水污染问题,使之重新焕发活力具有十分重要的意义。  相似文献   
9.
魏威  王辉 《环境与发展》2020,(2):208-209
环境统计工作是环境保护工作中的基础,是各级政府和环境保护行政主管部门制定环境保护政策和计划、加强环境监督管理和污染防治的重要依据。本文结合日常工作经验,就目前基层环境统计工作中存在的问题进行探讨,并提出一些建议。  相似文献   
10.
介绍了中山市空气质量多模式预报系统。对2015年3月—2016年2月的预报效果评估表明:系统可以较好地反映污染物的变化趋势但仍存在系统性偏差。通过对排放源清单的调整优化及对模式干沉降模块的改进使模式系统的偏差显著减小。总结并建立中山市污染天气案例库,发现在典型污染天气形势下,除O3-8 h外,其他污染物均值均能达到空气质量二级标准。未来将从2个方面提高中山市空气质量预报预警系统的实用性,包括逐步实现污染源排放清单的动态及时更新和提高极端气象条件下O3污染预报能力。  相似文献   
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