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151.
Michael Ackah Alfred Kwablah Anim Nafisatu Zakaria Juliet Osei Esther Saah-Nyarko Eva Tabuaa Gyamfi Delali Tulasi Sheriff Enti-Brown John Hanson Nash Owusu Bentil 《Environmental monitoring and assessment》2014,186(12):8499-8507
Twenty-three soft drink samples (i.e., four pineapple-based fruit drinks, eight citrus-based fruit juices, one soya-based drink, three cola carbonated drinks, one apple-based fruit drink, and six cocktail fruit drinks) were randomly purchased from retail outlets in an urban market in Accra and analyzed for the concentrations of iron, cobalt, cadmium, zinc, lead, and copper using flame atomic absorption spectrometry. The mean concentration of iron and cadmium were 0.723?±?0.448 mg/L and 0.032?±?0.012 mg/L, respectively. The mean cobalt concentration was 0.071?±?0.049 mg/L, while the mean Zn concentration in the samples was 0.060?±?0.097 mg/L. The mean concentrations of Pb and Cu in the fruit juice samples were 0.178?±?0.091 mg/L and 0.053?±?0.063 mg/L respectively. About 78 % of the samples exceeded the United States Environmental Protection Agency (USEPA) maximum contaminant level of 0.3 mg/L prescribed for iron, whereas all the samples exceeded the USEPA maximum contaminant level of 0.005 mg/L prescribed for cadmium. About 91 % of the samples exceeded the EU maximum contaminant level prescribed for lead insoft drinks. 相似文献
152.
Alfred Endres 《Journal of Environmental Economics and Management》1977,4(3):209-213
Ronald Coase asserted that voluntary two-party bargaining with zero transaction costs results in an optimal resource allocation, which is invariant with respect to the liability rule. It has been argued that nonseparabilities destroy the validity of Coase's theorem. In this paper it is shown that this criticism is based on implausible assumptions about the externality-receivers adjustment to the externality level. 相似文献
153.
Ulloa Hugo N. Constantinescu George Chang Kyoungsik Horna-Munoz Daniel Sepúlveda Steiner Oscar Bouffard Damien Wüest Alfred 《Environmental Fluid Mechanics》2019,19(3):667-698
Environmental Fluid Mechanics - We report novel results of a numerical experiment designed for examining the basin-scale hydrodynamics that control the mass, momentum, and energy distribution in a... 相似文献
154.
Elevated particulate matter concentrations in urbanlocations have normally been associated with local trafficemissions. Recently it has been suggested that suchepisodes are influenced to a high degree by PM10sources external to urban areas. To further corroboratethis hypothesis, linear regression was sought betweenPM10 concentrations measured at eight urban sites inthe U.K., with particulate sulphate concentration measuredat two rural sites, for the years 1993–1997. Analysis ofthe slopes, intercepts and correlation coefficientsindicate a possible relationship between urban PM10and rural sulphate concentrations. The influences of winddirection and of the distance of the urban from the ruralsites on the values of the three statistical parametersare also explored. The value of linear regression as ananalysis tool in such cases is discussed and it is shownthat an analysis of the sign of the rate of change of theurban PM10 and rural sulphate concentrations providesa more realistic method of correlation. The resultsindicate a major influence on urban PM10 concentrations from the eastern side of the UnitedKingdom. Linear correlation was also sought using PM10 data from nine urban sites in London and nearby ruralRochester. Analysis of the magnitude of the gradients andintercepts together with episode correlation analysisbetween the two sites showed the effect of transportedPM10 on the local London concentrations. This articlealso presents methods to estimate the influence of ruraland urban PM10 sources on urban PM10 concentrations and to obtain a rough estimate of thetransboundary contribution to urban air pollution from thePM10 concentration data of the urban site. 相似文献
155.
The Burruyacú district (Tucumán province, Argentina) is a farming frontier in the western Chaco plain, at the foothills of the sub-Andean mountain ranges, where agricultural land-uses are in conflict with the conservation and management of the Chaco forest. Over the last decades, large-scale farming rapidly expanded due to population pressure, attractive market prices, easy accessibility, favourable annual rainfall, fertile soils, and flexible land tenure. Cropland extension, mainly for heavily mechanized soybean production, has resulted in important reduction of the Chaco forest and also caused physical soil degradation, especially soil compaction, and soil erosion. Land suitability was assessed using the Food and Agriculture Organization (FAO) framework for a set of crops ecologically adapted to the area, including soybean, maize, wheat, sugarcane, citrus, and safflower. Only 16% of the study area has high suitability for most of the selected crops. Major limitations for cropping are low annual rainfall and flooding in the east of the study area, and topography (slope) and flooding in the west. As climate varies over relatively short periods of time, with recurrent cycles of dry and rainy years, land suitability for the selected crops was also assessed under extreme but realistic climatic conditions. Under rainy-year conditions, almost all the study area is unsuitable or marginally suitable for most of the crops. Under dry-year conditions, the study area is unsuitable for all crops, except safflower, which is more drought-resistant. This article proposes alternatives to the mono-cropping of soybean with the aim to help farmers make adequate decisions on land-use and management under deteriorating environmental conditions and for addressing the issue of competitive land uses in the context of land-use planning. 相似文献
156.
针对太湖地区稻田改种菜地后带来的土壤酸化现象,以碳酸钙与生物炭作为酸化改良剂,开展室内培养及多次淋洗模拟试验,比较两种改良剂对酸化菜地土壤持氮能力及酸化修复效果的影响.结果表明,基于碱缓冲曲线法,本试验用酸化菜地土壤每提高1个p H单位需向土壤中添加碳酸钙3.92×10-2mol·kg~(-1)或生物炭27.73 g·kg~(-1).无外源氮条件下碳酸钙添加使土壤氮矿化速率显著提高了37%,对土壤铵态氮、硝态氮含量影响不显著;生物炭添加使土壤氮矿化速率显著提高了35%~44%,且显著增加了土壤硝态氮含量42%~58%.模拟淋洗下,生物炭添加显著消减渗漏液体积24%,渗漏液氮浓度45%,显著减少氮淋失量42%~57%,而碳酸钙添加对渗漏液体积没有影响,增加了渗漏液中氮浓度,氮淋失量增加了12%~76%.淋洗后,各处理土壤p H值发生不同程度的降低,无外源氮条件下添加碳酸钙处理土壤p H值降幅最低,外源氮添加条件下生物炭添加处理降幅最低.由此可见,碳酸钙对酸化土壤修复效率较高,但在外源氮添加条件下降低了土壤持氮能力,更适用于酸化严重且需要休耕改良的菜地土壤;生物炭在维持土壤p H值的同时可以有效提高土壤矿质氮留存量,降低氮淋失,更适用于仍在高强度种植的菜地土壤. 相似文献
157.
Adjei Mensah Isaac Sun Mei Gao Cuixia Omari-Sasu Akoto Yaw Sun Huaping Ampimah Benjamin Chris Quarcoo Alfred 《Environmental science and pollution research international》2020,27(31):38674-38694
Environmental Science and Pollution Research - The main aim of this current study is to empirically scrutinize the determinants of energy consumption for 24 African countries sub-grouped into three... 相似文献
158.
Li Kaodui Wang Xiangmiao Musah Mohammed Ning Yi Murshed Muntasir Alfred Morrison Gong Zhen Xu Han Yu Xinyi Yang Xue Shao Keying Wang Li 《Environmental science and pollution research international》2022,29(40):60354-60370
Environmental Science and Pollution Research - Despite the considerable contributions of remittances to households and economic advancements, their environmental implications have received little... 相似文献
159.
160.
K. Knoch Alfred Wegener A. Prey Hartmann F. Baur A. Schmauss 《Die Naturwissenschaften》1926,14(33):774-778