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1.
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   
2.
• The long-period groundwater evolution was identified by hydrochemical signatures. • The dominant processes in the groundwater evolution were verified. • Groundwater quality in the coastal areas was susceptible to deterioration due to SI. • Groundwater contamination arose from fertilizer, livestock manure & domestic sewage. The evolution of hydrochemical compositions influenced by long-period interactions between groundwater and the geo-environment is a fundamental issue for exploring groundwater quality and vulnerability. This study systematically investigated the hydrochemical processes and anthropogenic interference occurring in the river basin by bivariate plots, Gibbs diagrams, saturation index, and the major ions ratios. Apparent changes in groundwater hydrochemistry have been observed in the study area, illustrating the origins of major ions are affected by various internal and external factors. Results highlighted that TDS varied from freshwater to brackish water, ranging between 187.90 and 2294.81 mg/L. Ca2+ and HCO3 are the dominant ions in the studied samples. The results gained by Gibbs diagrams, bivariate plots, saturation index, and the major ions ratios demonstrated that minerals dissolution/precipitation, cation exchange, and human inputs play crucial roles in the unconfined aquifers. Moreover, the overuse of nitrogen fertilizer, livestock manure, and industrial/domestic sewage led to nitrate and nitrite contamination and brought significant challenges to the surrounding hydrogeo-environment. The present study could make an unambiguous identification of natural processes and anthropogenic interventions influencing groundwater hydrochemistry’s long-period evolution and create a preliminary strategy for groundwater resources management.  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.
刘钰  曾妍妍  周金龙  闫志雲  白凡 《环境科学》2023,44(12):6778-6789
开展地下水污染风险评价研究是地下水污染防控的重要环节.以巴里坤-伊吾盆地平原区地下水为研究对象,构建DRSTIW模型进行地下水脆弱性评价;根据污染场地调查资料和土地利用类型划分点源和面源污染,进行地下水污染荷载评价;考虑地下水的原生价值、经济价值和生态价值进行地下水功能价值评价;利用ArcGIS的地图代数功能生成地下水污染风险评价图,采用ROC曲线验证地下水污染风险评价结果,通过计算G指数得到地下水污染风险空间冷热点分布,结合重心和标准差椭圆对热点变动情况进行定量分析.结果表明,研究区地下水污染风险整体较低,高污染风险区和较高污染风险区仅占研究区总面积的6.8%,主要位于伊吾县的淖毛湖镇、盐池镇,巴里坤县的奎苏镇、石人子乡、花园乡和兵团红山农场,该区域内地下水埋深较浅,土壤表层和包气带介质透水性能较强,吸附能力较差,加之污染源分布较集中,使得污染物易于迁移富集,在地下水高脆弱性和高污染荷载的双重作用下导致局部区域地下水污染风险升高.受人类活动影响,地下水污染风险在空间上存在一定的集聚现象,整体表现为由西北向东南演变的趋势.地下水污染风险评价结果为划分地下水污染防治区提供重要参考.  相似文献   
5.
This study investigated the water quality variation spanning 30 years (1986–2017) in 16 catchments of Hong Kong against different urbanization indices, namely, built area fraction; population; and product of population and built area fraction. Pearson correlations of three different periods of time (1988–1990, 1998–2000, and 2015–2017) indicated that water quality trends were dependent on the urbanization index. Total solids, nitrite-nitrogen, total phosphorus, electrical conductivity, dissolved oxygen, and flow rate had significant deteriorative trends (Pearson r > 0.5 and p < 0.05) with population and product of built area and population. Results also interpreted that built area fraction and product of built area and population were the worst and best indices that represented urbanization and/or its impacts, respectively. Mann-Kendall test for the entire 30 year period showed that water quality had improved with time with respect to certain water quality parameters (e.g., dissolved oxygen, ammoniacal nitrogen and total suspended solids). The results portrayed that although the urbanization of catchments had increased with time, the river water quality with respect to many parameters showed signs of improvement and the legislative measures implemented seemed to be effective in controlling pollution.  相似文献   
6.
明确硝酸盐的主要来源及转化过程对地下水氮污染防治和水资源开发利用具有重要意义.为了探明滇池周边浅层地下水中硝酸盐污染现状及来源,于2020年雨季(10月)和2021年旱季(4月)在滇池周边共采集73个浅层地下水样,运用水化学和氮氧同位素(δ15N-NO3-δ18O-NO3-)识别浅层地下水中硝酸盐的空间分布、来源及转化过程,并结合同位素混合模型(SIAR)定量评价不同来源氮对浅层地下水硝酸盐的贡献.结果表明,旱季浅层地下水中有40.5%的采样点ρ(NO3--N)超过地下水质量标准(GB/T 14848)Ⅲ类水质规定的20 mg·L-1,雨季超过47.2%的采样点ρ(NO3--N)超过20 mg·L-1.氮氧同位素和SIAR模型分析结果证明了土壤有机氮、化肥氮、粪肥和污水氮是浅层地下水硝酸盐的主要来源,以上氮源对旱季浅层地下水中硝酸盐的贡献率分别为13.9%、11.8%和66.5%,对雨季的贡献率分别为33.7%、31.1%和25.9%,而大气氮沉降贡献率仅为8.5%,对该区浅层地下水中硝酸盐来源贡献较小.硝化作用是旱季浅层地下水中硝态氮转化的主导过程,雨季以反硝化作用为主,且反硝化作用雨季比旱季明显.  相似文献   
7.
采用液液萃取处理水样,用气相色谱-串联质谱法测定样品中五氯酚及其钠盐,通过优化测定条件,使方法在1.00μg/L~500μg/L范围内线性良好。检出限和定量限分别为1.00μg/L和5.00μg/L,空白水样五氯酚钠3个质量浓度水平的加标回收率为89.8%~98.4%,5次平行试验测定结果的RSD为5.5%~10.7%。  相似文献   
8.
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   
9.
Concerns over the loss of biodiversity and ecosystem services in farmland have prompted the development of agri-environment policy measures aimed at reducing farming pressure and maintaining semi-natural habitats in farmed landscapes. However, further knowledge is needed to guarantee successful agri-environment measures implementation. The current study assessed the quantity and the quality of semi-natural habitats in farms across a gradient of farming intensities in two contrasting regions in Ireland. Policy protection seemed fundamental for semi-natural habitats preservation. Habitats not protected by agricultural policy relied on extensive farming and are in danger of disappearing if they are intensified or abandoned. Due to the lack of policy incentives for habitat quality, no correlations were found between farming intensity and share of semi-natural habitats with habitat quality. Therefore, extensive farming and retention of habitats alone may not reverse the decline of farmland quality and biodiverisity and, thus, measures incentivising the environmental quality may be more successful.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01344-6) contains supplementary material, which is available to authorized users.  相似文献   
10.
为了提升扬州市公共场所卫生状况和传染病防控能力,按照国家标准于2019年对扬州市宾馆(酒店)类、沐浴类、理发店类、美容店类和候车室类5类公共场所的健康危害因素(空气质量和公共用品用具)进行监测,按照《公共场所卫生指标及限值要求》(GB 37488—2019)进行评价。结果表明,共监测空气质量样品216份,合格率为84.26%,共监测公共用品用具1 414份,合格率为96.46%,不同场所的空气质量合格率和公共用品用具微生物指标合格率差异均具有统计学意义(P 0.05)。不同类型公共用品用具监测项目中,金黄色葡萄球菌的合格率最高(100%),而真菌总数的合格率最低(93.75%)。各类公共用品用具中,拖鞋合格率最低(91.67%),床单相对较高(99.70%)。扬州市公共卫生状况总体良好,在空气质量监测中,物理项目和微生物项目合格率较低,在公共用品用具监测中,细菌总数和大肠菌群存在不合格现象。  相似文献   
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