The use of polycyclic aromatic hydrocarbons as a particulate tracer in the water column of Gaoping (Kaoping) Submarine Canyon

Time-series samples of settling particles were collected in the water column of Gaoping (formerly spelled Kaoping) Submarine Canyon (KPSC) with two sediment traps on taut-line moorings deployed at two different depths (60 and 280 m) between May 26 and June 27, 2004. Average total polycyclic aromatic hydrocarbon (PAH) concentrations of upper and lower trap array samples were 310 ± 61 ng g^− 1 dw (range: 200–440) and 240 ± 36 ng g^− 1 dw (range: 180–290), respectively. Principal component analysis results suggest that PAH sources in the trap-collected particles included diesel vehicle/coal burning, diagenetic sources, and petroleum release. PAH downward fluxes based on settling particles were estimated to be 12–44 μg m^− 2 d^− 1. These values are higher than those reported in the literature for most coastal areas. During the sampling period, both traps were significantly tilted by tidal current and fluctuated vertically. The upper traps experienced greater vertical movements, thus their particle characteristics (e.g., POC, particle mass, and fine particle fraction) varied more than those of the lower traps. Hourly depth variations of the tilted sediment trap array were echoed by the corresponding total PAH concentrations. Moreover, the PAH composition of the collected particles was related to the flow direction and speed. These observations suggest that PAHs can be used as an effective chemical tracer for the transport of terrestrial and marine particulates in a complex aquatic environment like Gaoping (Kaoping) Submarine Canyon.     

潜艇空气污染与污染检测技术

本文根据国内外潜艇舱室大气污染的状况,论述了舱室主要污染物的来源、对人体的危害和污染物检测技术及发展趋势,为我国开展潜艇大气控制技术研究提供依据。     

Natural and anthropogenic hydrocarbons in the water column of the Ross Sea (Antarctica)

In the framework of the Italian Research Programme in Antarctica (PNRA) an oceanographic cruise was carried out between December 2000 and February 2001 in the Western Ross Sea. n-Alkanes and PAHs concentrations were analysed in sea-water samples collected at different depths at four sites (D, B, CA2, and CA). Vertical profiles of pressure, temperature, salinity and fluorescence were also performed in order to distinguish the water masses present in the sampling areas. n-Alkanes concentrations were consistent with those found in the same area during previous expeditions and showed higher values in the particulate due to the low temperatures. n-Alkanes profiles exhibited different features in the dissolved and particulate phases. The dissolved phase was characterised by a bimodal distribution with two maxima at C16 and C24 and prevalent compounds in the range C15–C32 whereas particulate was strongly dominated by long chain n-alkanes C23–C34 with C24 (Site B, CA and CA2) or C32 (Site B) as Cmax. CPI values and Pr/Ph ratios suggested a prevalent biogenic origin for aliphatic hydrocarbons. n-Alkanes vertical distributions were affected by the dynamic of the pack-ice melting and phytoplankton activity as well by the chemical–physical properties of water masses. Higher n-alkanes values were found in the High Salinity Shelf Waters (HSSW), lower n-alkanes values were found in the Antarctic Surface Waters (AASW) and Modified Circumpolar Deep Water (MCDW).The low PAHs concentration levels confirmed the still pristine character of the Antarctic environment. Neither particular trend in total PAHs concentrations along the water column and nor correlations with the most characteristic water masses of the investigated area of the Ross Sea were observed, except that total PAH higher concentrations were generally observed in correspondence of HSSW.     

Cruise activity and pollution: The case of Barcelona

One of the main causes of mortality worldwide is air pollution. To tackle this problem, local, regional and national governments have implemented policies to reduce emissions from industrial and on-road sources. However, when these policies are being designed, shipping emissions are often overlooked. There has been a drastic increase in the demand for cruises and its economic relevance is also growing in port-cities. Barcelona is Europe’s leading cruise port, and it is located near the centre of the city. In this context, this paper analyses the impact of cruise ships in the air quality of the entire city of Barcelona using a dataset with information about pollutants and the number of cruises arriving to the port. We show that there is a direct impact between cruises staying at the port and city pollution. Additionally, the size and age of the cruise also affect air quality. The larger (or newer) the cruise is, the higher the emission generated. Moreover, our simulations show that the whole city is affected by these emissions.     

Analysis of thirty years evolution of urban growth,transport demand and supply,energy consumption,greenhouse and pollutants emissions in Greater Cairo

The objective of the paper is to analyze evolution of urbanization, transport demand and supply in Greater Cairo (GC) over the last three decades of the 20th century. This is in addition to investigating the impact of city growth on energy consumption and emissions from transport. It utilizes results of 1971, 1978, 1987, 1998 and 2001 travel demand surveys, undertaken during the corresponding GC transport studies; each was published a year or two later. No further transport studies have been carried out in GC over the past decade and in view of the current political situation, it is not envisaged that similar studies will be undertaken in the near future. The analysis includes the evolution of daily trips, trip purpose share, modal share and number of cars. More recent trends for 2006/2007 vehicle registration by type and size are given. The evolution of transport supply covers projects until early 2012. In parallel estimates of the evolution of energy consumption and cost, emissions of greenhouse gases (CO₂) and pollutants (CO, HC and NO_x) are given for 1971/2001. The adopted estimation methodology is summarized. Comparative analysis of relevant evolution indexes and trends of growth between 1971 and 2001, taking the former as base year, is given. Land use and transport policies and projects that in some cases helped, directly or indirectly, to reduce traffic congestion, or at least prevented an increase, are addressed, commenting on their outcomes. Thus, transferable experience are useful to sister cities benefiting from successes and avoiding drawbacks. The evolution of the impact of GC metro on energy consumption and cost, and GHG emissions is given for 1987/2001, assuming the scenario “metro did not exist”. More recent impact analysis is given for 2007/2008, as the data allowed estimating traffic volumes that would have been added to the congested metro corridors under the above scenario; and the related fuel consumption and cost and GHGs. The paper ends with conclusions on GC evolution, learned lessons and suggests repeating similar work in other mega cities of the developing countries. Further research is emphasized, e.g., modeling the relationship between land use, transport, energy and emissions; modeling emission factors by vehicle type; and studying fuel-subsidy-reduction scenarios and their socio-economic effects.     

汽油车燃油蒸发污染物的控制系统研究

本文介绍燃油蒸发污染物控制系统（包括活性碳罐、清洗阀等主要部件）的研制、试验分析及对发动机性能影响，表明整个系统设计合理、工作可靠、净化节能效果明显。