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971.
Richard T. Carson Maria Damon Leigh T. Johnson Jamie A. Gonzalez 《Journal of environmental management》2009
In marine areas throughout the world where recreational boats are densely located, concentrations of copper in the water are being found to be in excess of government standards, due to the hull coatings used on these boats. Copper-based hull coatings are intended to be antifouling in that they retard the growth of algae, barnacles and tubeworms; but alternatives exist that can eliminate the harm that copper contamination does to marine organisms. A variety of policy options are available to mandate or provide economic incentives to switch to these less harmful alternatives. This paper puts forth a conceptual framework for thinking about how to design and evaluate alternative policies to transition to nontoxic boat hulls, drawing from the authors' experience designing a policy for use in San Diego Bay. Many of the issues raised are broadly applicable to environmental problems where the solution involves a large-scale replacement of durable consumer goods. 相似文献
972.
Diversity of Soil Nematodes in Areas Polluted with Heavy Metals and Polycyclic Aromatic Hydrocarbons (PAHs) in Lanzhou,China 总被引:1,自引:0,他引:1
This study investigated the soil nematode community structure along the Yellow River in the Lanzhou area of China, and analyzed
the impact of heavy metals (Cd, Pb, Cr, Cu, and Zn) and polycyclic aromatic hydrocarbons (PAHs) on the nematode community.
Soil samples from five locations (named A–E), which were chosen for soil analysis, showed significant differences in their
heavy metal content (p < 0.01), as well as in the variety of nematodes (up to 41 genera) and families (up to 20) that were present. The different
samples also differed significantly in the total PAH content (p < 0.05), as well as the six types of PAH present. Sites A–C showed the most severe contamination with heavy metals and PAHs;
these sites had the lowest abundance of fungivores and omnivore/predators, but the proportion of bacteriovores was the highest
(p < 0.05). Site E, in contrast, showed only minor pollution with heavy metals and PAHs, and it contained the highest abundance
of plant parasites (p < 0.05). Several nematode ecological indicators were found to correlate with concentration of soil pollutants at all the
sites tested: the maturity index (MI, in addition to plant parasites), plant parasite index (PPI), ΣMI (including all the
soil nematodes), Shannon-Wiener diversity index (H′′), and Wasilewska index (WI). Disturbance to the soil environment was more severe when MI, ΣMI, and H′ values were lower. The results of the study show that the abundance and structure of the soil nematode communities in the
sampling locations were strongly influenced by levels of heavy metals and PAHs in the soil. They also show that the diversity
index H′ and the maturity index can be valuable tools for assessing the impact of pollutants on nematodes. 相似文献
973.
Observations of Atmospheric Nitrogen and Phosphorus Deposition During the Period of Algal Bloom Formation in Northern Lake Taihu,China 总被引:5,自引:1,他引:4
Cyanobacterial blooms in Lake Taihu occurred at the end of April 2007 and had crucial impacts on the livelihood of millions
of people living there. Excessive nutrients may promote bloom formation. Atmospheric nitrogen (N) and phosphorus (P) deposition
appears to play an important role in algal bloom formation. Bulk deposition and rain water samples were collected respectively
from May 1 to November 30, 2007, the period of optimal algal growth, to measure the bulk atmospheric deposition rate, wet
deposition rate, and dry deposition rate for total nitrogen (TN; i.e., all species of nitrogen), and total phosphorus (TP;
i.e., all species of phosphorus), in northern Lake Taihu, China. The trends of the bulk atmospheric deposition rate for TN
and the wet deposition rate for TN showed double peaks during the observation period and distinct influence with plum rains
and typhoons. Meanwhile, monthly bulk atmospheric deposition rates for TP showed little influence of annual precipitation.
However, excessive rain may lead to high atmospheric N and P deposition rates. In bulk deposition samples, the average percentage
of total dissolved nitrogen accounting for TN was 91.2% and changed little with time. However, the average percentage of total
dissolved phosphorus accounting for TP was 65.6% and changed substantially with time. Annual bulk atmospheric deposition rates
of TN and TP during 2007 in Lake Taihu were estimated to be 2,976 and 84 kg km−2 a−1, respectively. The results showed decreases of 34.4% and 78.7%, respectively, compared to 2002–2003. Annual bulk deposition
load of TN for Lake Taihu was estimated at 6,958 t a−1 in 2007 including 4,642 t a−1 of wet deposition, lower than the values obtained in 2002–2003. This may be due to measures taken to save energy and emission
control regulations in the Yangtze River Delta. Nevertheless, high atmospheric N and P deposition loads helped support cyanobacterial
blooms in northern Lake Taihu during summer and autumn, the period of favorable algal growth. 相似文献
974.
Arun Kansal Mukesh Khare Chandra Shekhar Sharma 《Journal of Environmental Planning and Management》2009,52(7):881-899
This study estimates minimum marginal health benefits (morbidity reduction only) of air pollution control and total health benefits arising from regulatory intervention regarding the adoption of the World Bank emission guidelines (WBEG) for thermal power plants (TPPs) in Delhi. The Industrial Source Complex-Short-Term Version–3 (ISCST3) model has been used to estimate the contribution to air pollution from TPPs. The household health production function (avertive behaviour) has been used to value health benefits of air pollution control. The study revealed that the ambient air pollution due to TPPs is reduced by between 62.17% to 83.45% by adopting the WBEG. Annual marginal benefit due to reduction in exposure to air pollution by 1 μg m?3 is estimated to be US$0.353 per person. Total annual health benefits for adopting the WBEG for TPPs are estimated at US$235.19 million. This study provides a novel methodology to evaluate health benefits of regulatory intervention. 相似文献
975.
成都平原农用土壤重金属污染现状及防治对策 总被引:4,自引:0,他引:4
随着工业化进程的加快和农业生产中化肥和农药不合理施用使得农用土壤重金属污染风险逐渐增大。本文对成都平原农用土壤和农作物重金属污染现状进行了综述,发现农用土壤和蔬菜中重金属污染均以Pb、Cd和Hg三种元素为主。分析了重金属离子在土壤一植物系统中迁移的一般规律及其影响因子,分析了农用土壤重金属污染的主要原因,为预防和防治污染提供了一些建议。 相似文献
976.
977.
随着社会经济的发展,突发性环境污染事故频繁发生。为有效预防和控制突发性环境污染事故,各国开发了相应的应急管理系统,为污染事故处置提供应对技术和决策支持。本文综合论述了国内外突发环境污染事故应急管理系统的开发和应用情况、服务内容及特点,并对我国应急管理的发展提出建议。 相似文献
978.
环境库兹涅茨曲线假说在中国的经验研究 总被引:3,自引:0,他引:3
改革开放以来,中国年均98%的经济持续增长举世瞩目,然而对经济增长所付出的环境代价却存在着诸多争议。环境库兹涅茨曲线(EKC)假说是对环境 收入关系研究的经典表述,可以直观地展现环境与收入变化的关系。在前人研究EKC时运用单一或多个单一指标测量污染程度存在缺陷的基础上,基于 1982~2006年中国6类环境污染物,用改进的熵值法计算出代表我国整体环境污染状况的环境污染指数,利用协整检验来研究中国环境库兹涅茨曲线的存在性及其“本土化”特征,发现与一般发达国家和新兴发展中国家的“倒U”型环境库兹涅茨曲线不同,中国综合环境污染模型呈“正U”型,以21世纪初为分界点,之前环境污染水平不断下降,之后环境污染又开始有所恶化;利用脉冲响应函数来考察环境污染和经济增长的互动关系,发现经济增长在追溯期内对环境污染均为正向影响,而环境污染仅在短期对经济增长有促进作用。这一研究旨在为制定符合中国国情的环境、经济政策,实现经济与环境协调发展提供理论依据. 相似文献
979.
V. V. Tuzhilkina 《Russian Journal of Ecology》2009,40(4):227-232
To estimate the response of conifers to long-term industrial air pollution at the pigment system level, the dynamics of photosynthetic pigments have been studied in needles of Scots pine (Pinus sylvestris L.) and Siberian spruce (Picea obovata Ledeb.) growing at different distances from the emission source (a pulp and paper mill). It has been shown that the pigment apparatus of spruce. The results show that in spruce, unlike in pine, the pigment apparatus remains unchanged under the effect of weak pollution. Long-term exposure at high levels of industrial emission results in suppression of chlorophyll and carotenoid syntheses in pine but stimulates pigment production in spruce. An increase in the contents of pigments in the needles of conifers growing in the impact zone of the pulp and paper mill reflects a compensatory mechanism of adaptation of their pigment system to long-term stress exposure. 相似文献
980.
V. E. Zverev 《Russian Journal of Ecology》2009,40(4):254-260
Long-term monitoring of mountain birch populations (1992–2006) was performed in 14 test plots located at distances of 1 to 63 km from the copper-nickel smelter in Monchegorsk (Murmansk oblast) and differing in the degree of disturbance. In the period from 1999 to 2006, atmospheric emissions of sulfur dioxide and heavy metals amounted to only one-third of those between 1992 and 1998, but birch mortality in heavily polluted areas (with nickel concentrations in leaves exceeding 160 mg/kg) remained at the same level, being absent (as previously) in less polluted areas. Throughout the observation period, birch recruitment was observed only in areas where nickel concentrations in the leaves were below 160 mg/kg; i.e., this concentration proved to be the threshold with respect to both mortality and recruitment of mountain birch. The course of demographic processes in its populations has remained unchanged after the reduction of emissions, confirming the hypothesis of the “inertial“ effect of industrial emissions on ecosystems. In some areas of industrial barrens, mountain birch may perish completely within the next decade. 相似文献