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Metal concentrations and mobility in marine sediment and groundwater in coastal reclamation areas: a case study in Shenzhen, China 总被引:2,自引:0,他引:2
The concentrations of metals in the buried marine sediment and groundwater were differently affected by land reclamation. Nine metals (V, Cr, Mn, Co, Ni, Cu, Zn, Cd and Pb) in sediment and coastal groundwater from reclamation areas in Shenzhen were examined. The gradually decreased concentrations (V, Cr, Mn, Ni, Cu, Zn) in sediment and relatively higher concentrations (V, Cr, Mn, Co, Ni, Cu and Cd) in groundwater within reclamation areas were observed. The increase of V, Cr, Mn, Ni, Cu and Cd concentrations in groundwater within reclamation areas subsequently after land reclamation should be resulted from the mobilization of these metals accumulated in the sediment. These metals appear to be easily mobilized from solid phase to solution phase after reclamation. The physico-chemical changes such as reduction in pH and salinity in water environment induced by land reclamation appear to be responsible for metal mobility in the sediment-groundwater system. 相似文献
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随着城市的快速发展,城市生活垃圾对环境的危害越来越大,已经成为影响城市居住环境的重要污染源,如何进行城市生活垃圾的收集与处理显得至关重要。米东区作为乌鲁木齐市新型工业城区的代表,其经济虽然取得了飞速发展,但其城市居住环境却未得到足够地重视。鉴于此,围绕乌鲁木齐市新型工业城区的生活垃圾分类收集和处理现状展开了社会调查,选取乌鲁木齐市米东区作为靶区,随机选取70户人家进行了入户问卷调查,对调查结果进行了统计分析,得出了乌鲁木齐市米东区家庭生活垃圾分类收集及处理的特点,进而指出了新型工业城区垃圾分类工作存在的主要问题,根据影响城市家庭生活垃圾产生量的因素,针对如何更好的实现垃圾的分类收集工作提出了相应的建议。 相似文献
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Hatch L Clark C Merrick R Van Parijs S Ponirakis D Schwehr K Thompson M Wiley D 《Environmental management》2008,42(5):735-752
In 2006, we used the U.S. Coast Guard’s Automatic Identification System (AIS) to describe patterns of large commercial ship
traffic within a U.S. National Marine Sanctuary located off the coast of Massachusetts. We found that 541 large commercial
vessels transited the greater sanctuary 3413 times during the year. Cargo ships, tankers, and tug/tows constituted 78% of
the vessels and 82% of the total transits. Cargo ships, tankers, and cruise ships predominantly used the designated Boston
Traffic Separation Scheme, while tug/tow traffic was concentrated in the western and northern portions of the sanctuary. We
combined AIS data with low-frequency acoustic data from an array of nine autonomous recording units analyzed for 2 months
in 2006. Analysis of received sound levels (10–1000 Hz, root-mean-square pressure re 1 μPa ± SE) averaged 119.5 ± 0.3 dB at
high-traffic locations. High-traffic locations experienced double the acoustic power of less trafficked locations for the
majority of the time period analyzed. Average source level estimates (71–141 Hz, root-mean-square pressure re 1 μPa ± SE)
for individual vessels ranged from 158 ± 2 dB (research vessel) to 186 ± 2 dB (oil tanker). Tankers were estimated to contribute
2 times more acoustic power to the region than cargo ships, and more than 100 times more than research vessels. Our results
indicate that noise produced by large commercial vessels was at levels and within frequencies that warrant concern among managers
regarding the ability of endangered whales to maintain acoustic contact within greater sanctuary waters.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
669.
This study examines the impact of the creation of marine protected areas (MPAs), from both economic and biological perspectives. In particular, we examine the effects of protected patches and harvesting on resource populations. We conclude that protected patches are an effective means of conserving resource populations, even though extinction cannot be prevented in all cases. We discuss the dynamic optimization of a harvest policy by choosing E(t), the harvesting effort, as the dynamic variable. We also discuss the optimal equilibrium harvest policy and explain the biological and bioeconomic interpretations of the results. 相似文献
670.
Samuli Korpinen Laura Uusitalo Marie C. Nordstrm Jan Dierking Maciej T. Tomczak Jannica Haldin Silvia Opitz Erik Bonsdorff Stefan Neuenfeldt 《Ambio》2022,51(7):1687
Ecosystem-based management requires understanding of food webs. Consequently, assessment of food web status is mandatory according to the European Union’s Marine Strategy Framework Directive (MSFD) for EU Member States. However, how to best monitor and assess food webs in practise has proven a challenging question. Here, we review and assess the current status of food web indicators and food web models, and discuss whether the models can help addressing current shortcomings of indicator-based food web assessments, using the Baltic Sea as an example region. We show that although the MSFD food web assessment was designed to use food web indicators alone, they are currently poorly fit for the purpose, because they lack interconnectivity of trophic guilds. We then argue that the multiple food web models published for this region have a high potential to provide additional coherence to the definition of good environmental status, the evaluation of uncertainties, and estimates for unsampled indicator values, but we also identify current limitations that stand in the way of more formal implementation of this approach. We close with a discussion of which current models have the best capacity for this purpose in the Baltic Sea, and of the way forward towards the combination of measurable indicators and modelling approaches in food web assessments. Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01692-x. 相似文献