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1.
港口工程对沿海环境的影响 总被引:1,自引:0,他引:1
海洋的许多生态参数,如溶解氧浓度和温度等均与环流有关,所以环流的流态对海洋环境的影响十分显著。在海中建造各种建筑物必然会妨碍水体运动,从而影响海洋环境。本文旨在研究港口建筑物对环流运动的影响和由此而引起的环境影响。 文中提出一个可供估算水文参数和废水耗氧量变化的简易数学模型。对于废水引起的富营养化效应也做了分析研究。 在港口工程规划设计阶段,必须进行环境生态影响的研究,如果港口附近有污水排放口,进行环境影响分析尤为重要。 本文介绍的方法,曾应用于靠近雅典城市污水排放区的比雷埃夫斯港的扩建工程。分析表明,如果按照原来的设计进行施工,而忽视工程引起的环境影响,其结果必然导致明显的生态变化。 相似文献
2.
在诺贝尔奖得主保罗·塞缪尔森首先提出的经济理论中,有这样一种见解,即不能指望不受控制的市场会保护环境。按照这一理论,清洁的空气和水属于“公共消费品”,其价值在市场过程中是得不到充分反映的。那些可能制造污染的人不会考虑他们行为的社会成本,而只关心自身承担的成本;此外,由于清洁环境的工作甚至可以使那些袖手旁观者也蒙受其益,如此一来,人人都会自然而然地想坐享其成。同样,如果市场不能立竿见影地反映出保存多样化生物或拯救具体物种的利益,土地拥有者也不会愿意为公益而出钱保护环境。这一理论认为,如果没有政府干预,环境就得不到充分保护。 相似文献
3.
西澳大利亚布罗克曼稀有金属矿化,是富含挥发份和不相容元素(例如Zr、IJf、Nb、Ta、Be、Y和REE及Ga等)的粗面岩岩浆发生早期火山碎屑喷发的结果。矿化呈三。粒状(<20μm),是由于相对简单的岩浆前身矿物(如铌铁矿和钻石),在岩浆喷发后保存于灰流凝灰岩[奈厄比厄姆(Niobium)凝灰岩]中的岩浆期后富F溶液的作用下,发生蚀变和再活化的结果。球粒陨石标准化的REE分布模式显示,矿体强烈富集HREE。胶质锆石是HREE主要载体,浸染状氟碳铈矿(±氟碳钙铈矿和直氟碳钙铈矿)是LREE的载体,晚期方解石脉中的羟硅滚石是Be的载体。Ga赋存于基质K云母中。上覆于奈厄比厄姆凝灰岩的粗面岩流含有许多类似的矿石矿物,但含量略有不同。 相似文献
4.
Walter R Stahel 《中国人口.资源与环境(英文版)》2007,5(4):3-19
From an economic point of view, the industrial economy is efficient to overcome situations of a scarcity of goods. From a technological point of view, the resource efficiency of the manufacturing processes of the industrial economy has been permanently improved during the last 200 years. In addition, cleaner processes have been developed. However, from an ecologic point of view, an increasing world population with increasing consumption has produced a "global footprint" which approaches the carrying capacity of the planet. A circular economy and its high-value spin-offs-a lake economy and a performance or functional service economy-can fulfil customers' needs with considerably less resource consumption, less environmental impairment in production and considerably less end-of-life product waste, especially in situations of affluence, when a considerable stock of physical goods and infrastructures exists. Also, in situations of a scarcity of natural resources, both energy and materials, often characterised by rapidly rising resource prices, the economic actors of a circular economy have a high competitive advantage over the actors of the industrial economy, due to much lower procurement costs for materials and energy. From a social point of view, a circular economy increases the number of skilled jobs in regional enterprises. However, the shift from a linear manufacturing economy to a circular or service economy means a change in economic thinking from flow (throughput) management to stock (asset) management: in a manufacturing economy with largely unsaturated markets, total wealth increases through accumulation as resource throughput (flow) is transformed into a higher stock of goods of better quality (but in a manufacturing economy with largely saturated markets, wealth represented by the stock of goods will no longer increase); in a circular or service economy, total wealth increases through a smart management of existing physical assets (stock) that are adapted to changes in both technology and customer demand. This second approach not only applies to physical capital but equally to social capital, such as health and education and green GDP. To measure the social wealth of a population, it is not the amount of money spent on schools and hospitals that matters, butif this expenditure has led to a better education of the students, and a better health of the people. 相似文献
5.
环境问题的产生很大程度上是过度消费导致的。青年是社会的未来。青年能否 转换消费观念,树立绿色消费模式,积极投身保护环境,直接决定了未来社会 的发展。 相似文献
6.
Lakshminarayana JS O'Neill HJ Jonnavithula SD Léger DA Milburn PH 《Environmental pollution (Barking, Essex : 1987)》1992,76(3):201-210
Preliminary results are reported from a co-operative study between Agriculture Canada and Environment Canada on environmental impacts of atrazine measured in a field stream receiving agricultural drainage. Systematically, tile drained plots of known crop rotation, area, flow and pesticides use were used in the study. A maximum tile drainage concentration of 13.9 microg liter(-1) atrazine was measured while the maximum measured stream concentration was 1.89 microg liter(-1). Phytoplankton and zooplankton samples were collected on a bi-monthly basis during the growing season. The study indicated possible negative impacts of low concentrations of atrazine on planktonic drift populations, when natural stream flow was reduced, resulting in a lower dilution capacity. A 20 m section of the stream was affected by the tile drainage waters as measured by the resident biological community. Both atrazine and ambient environmental conditions were felt to be contributing to the measured results. No negative impacts on planktonic drift populations were evident beyond 50 m downstream of the tile drainage and stream confluence. 相似文献
7.
Gabriela P. Mendes Vivian M.A. Magalhães Lélia C.R. Soares Rayanne M. Aranh Claudio A.O. Nascimento Marilda M.G.R. Viann Osvaldo Chiavone-Filho 《环境科学学报(英文版)》2020,32(4):67-77
Chemical oxidation was applied to an artificially contaminated soil with naphthalene (NAP). Evaluation of NAP distribution and mass reduction in soil, water and air phases was carried out through mass balance. Evaluation of NAP distribution and mass reduction in soil, water and air phases was carried out through mass balance. The importance of the air phase analysis was emphasized by demonstrating how NAP behaves in a sealed system over a 4 hr reaction period. Design of Experiments method was applied to the following variables: sodium persulfate concentration [SP], ferrous sulfate concentration [FeSO4], and pH. The system operated with a prefixed solid to liquid ratio of 1:2. The following conditions resulted in optimum NAP removal [SP] = 18.37 g/L, [FeSO4] = 4.25 g/L and pH = 3.00. At the end of the 4 hr reaction, 62% of NAP was degraded. In the soil phase, the chemical oxidation reduced the NAP concentration thus achieving levels which comply with Brazilian and USA environmental legislations. Besides the NAP partitioning view, the monitoring of each phase allowed the variabilities assessment over the process, refining the knowledge of mass reduction. Based on NAP distribution in the system, this study demonstrates the importance of evaluating the presence of semi-volatile and volatile organic compounds in the air phase during remediation, so that there is greater control of the system as to the distribution and presence of the contaminant in the environment. The results highlight the importance of treating the contaminant in all its phases at the contaminated site. 相似文献
8.
Bruno T. Franzin Filipe C. Guizellini Diego V. de Babos Ossamu Hojo Iêda Ap. Pastre Mary R.R. Marchi Fernando L. Fertonani Cristina M.R.R. Oliveira 《环境科学学报(英文版)》2020,32(3):238-251
Air pollution causes deleterious effects on human health with aerosols being among the most polluting agents.The objective of this work is the characterization of the PM_(2.5) and PM_(10) aerosol mass in the atmosphere.The methods of analysis include WD-XRF and EDS.Data were correlated with meteorological information and air mass trajectories(model HYSPLIT)by multivariate analysis.A morphological structural analysis was also carried out to identify the probable sources of atmospheric aerosols in the city of Sao Jose do Rio Preto,Brazil.The mean mass concentration values obtained were 24.54 μg/m~3 for PM_(10),above the WHO annual standard value of 20 μg/m~3 and 10.88 μg/m~3 for PM_(2.5) whose WHO recommended limit is10 μg/m~3.WD-XRF analysis of the samples revealed Si and Al as major components of the coarse fraction.In the fine fraction,the major elements were Al and S.The SEM-FEG characterization allowed identifying the morphology of the particles in agglomerates,ellipsoids and filaments in the PM_(10),besides spherical in the PM_(2.5).The analysis by EDS corroborated WD-XRF results,identifying the crustal elements,aluminosilicates and elements of anthropogenic origin in the coarse fraction.For the fine fraction crustal elements were also identified;aluminosilicates,black carbon and spherical particles(C and O) originating from combustion processes were predominant.The use of multivariate analysis to correlate air mass trajectories with the results of the morpho-structural characterization of the particulate matter allowed confirmation of the complex composition of the particles resulting from the combination of both local and long-distance sources. 相似文献
9.
Shelter, housing and recovery: a comparison of u.s. Disasters 总被引:3,自引:0,他引:3
In this paper we examine the issues associated with the temporary sheltering and housing of victims after natural disasters in the United States. Specific topics addressed include differential access to shelter and housing aid according to social class, ethnicity and related demographic factors; the relationship between post-disaster shelter and housing and long-term recovery; the role of social support networks in the sheltering of victims; and the implications of the research for the provision of shelter and housing aid after disasters. 相似文献
10.
Pleijel H Skärby L Wallin G Selldén G 《Environmental pollution (Barking, Essex : 1987)》1991,69(2-3):151-168
Spring wheat (Triticum aestivum L., cv. Drabant) was exposed to different concentrations of ozone in open-top chambers for two growing seasons, 1987 and 1988, at a site located in south-west Sweden. The chambers were placed in a field of commercially grown spring wheat. The treatments were charcoal-filtered air (CF), non-filtered air (NF) and non-filtered air plus extra ozone (NF(+)). In 1988, one additional ozone concentration (NF(++)) was used. Grain yield was affected by the ozone concentration of the air. Air filtration resulted in an increase in grain yield of about 7% in both years, compared to NF. The addition of ozone (NF(+), NF(++)) reduced grain yield and increased the content of crude protein of the grain in both years. Filtration of the air had no significant effect on the content of crude protein, compared to NF. The results showed a strong positive chamber effect on grain yield in the cold and wet summer of 1987. In 1988, there was no net chamber effect on grain yield. The relative differences between the CF, NF and NF(+) treatments with respect to grain yield were of the same magnitude in the two years, despite the very different weather conditions. 相似文献