典型印染废水处理过程中芳香烃化合物的污染特征及污泥生态风险评价

采用GC-MS测定了典型综合印染废水处理厂废水和污泥中芳香烃化合物的含量.结果表明,原水中苯系物总量为203.96±15.18μg·L-1,其中二甲苯占62.7%,尾水中苯系物总量为0.2±0.029μg·L-1,整个处理工艺对苯系物的去除效率为99%.原水中多环芳烃(PAHs)总浓度达1349.51±35.77 ng·L-1,以3—6环为主,主要富集在颗粒物上.整个工艺对PAHs的去除效率为95%,尾水中PAHs总浓度为65.81±20.99ng·L-1,以2—3环为主.干污泥中PAHs含量高达2996.10±151.0 ng·g-1,污泥吸附为水相中PAHs去除的主要机理之一.印染污泥直接填埋或农用会引起潜在的生态危害.     

Environmental Equity and the Role of Public Policy: Experiences in the Rijnmond Region

This Φ Ψ study of environmental equity uses secondary quantitative data to analyze socioeconomic disparities in environmental conditions in the Rijnmond region of the Netherlands. The disparities of selected environmental indicators—exposure to traffic noise (road, rail, and air), NO₂, external safety risks, and the availability of public green space—are analyzed both separately and in combination. Not only exposures to environmental burdens (“bads”) were investigated, but also access to environmental benefits (“goods”). Additionally, we held interviews and reviewed documents to grasp the mechanisms underlying the environmental equity situation, with an emphasis on the role of public policy. Environmental equity is not a priority in public policy for the greater Rotterdam region known as the Rijnmond region, yet environmental standards have been established to provide a minimum environmental quality to all local residents. In general, environmental quality has improved in this region, and the accumulation of negative environmental outcomes (“bads”) has been limited. However, environmental standards for road traffic noise and NO₂ are being exceeded, probably because of the pressure on space and the traffic intensity. We found an association of environmental “bads” with income for rail traffic noise and availability of public green space. In the absence of regulation, positive environmental outcomes (“goods”) are mainly left up to market forces. Consequently, higher-income groups generally have more access to environmental “goods” than lower-income groups.     

Surface geophysical exploration: developing noninvasive tools to monitor past leaks around Hanford’s tank farms

A characterization program has been developed at Hanford to image past leaks in and around the underground storage tank facilities. The program is based on electrical resistivity, a geophysical technique that maps the distribution of electrical properties of the subsurface. The method was shown to be immediately successful in open areas devoid of underground metallic infrastructure, due to the large contrast in material properties between the highly saline waste and the dry sandy host environment. The results in these areas, confirmed by a limited number of boreholes, demonstrate a tendency for the lateral extent of the underground waste plume to remain within the approximate footprint of the disposal facility. In infrastructure-rich areas, such as tank farms, the conventional application of electrical resistivity using small point-source surface electrodes initially presented a challenge for the resistivity method. The method was then adapted to directly use the buried infrastructure, specifically the steel-cased wells that surround the tanks, as “long” electrodes for both transmission of electrical current and measurements of voltage. Overcoming the drawbacks of the long electrode method has been the focus of our work over the past 7 years. The drawbacks include low vertical resolution and limited lateral coverage. The lateral coverage issue has been improved by supplementing the long electrodes with surface electrodes in areas devoid of infrastructure. The vertical resolution has been increased by developing borehole electrode arrays that can fit within the small-diameter drive casing of a direct push rig. The evolution of the program has led to some exceptional advances in the application of geophysical methods, including logistical deployment of the technology in hazardous areas, development of parallel processing resistivity inversion algorithms, and adapting the processing tools to accommodate electrodes of all shapes and locations. The program is accompanied by a full set of quality assurance procedures that cover the layout of sensors, measurement strategies, and software enhancements while insuring the integrity of stored data. The data have been shown to be useful in identifying previously unknown contaminant sources and defining the footprint of precipitation recharge barriers to retard the movement of existing contamination.     

Sample preparation for GC analysis of selected pesticides in surface water.

A new isolation procedure for the determination of nitrogen/phosphorous containing pesticides and organochlorine pesticides in water was tested, and statistical evaluation of the recoveries was performed. The procedure, designed specifically for the analysis of semi-volatile compounds in water containing Suspended Particulate Matter (SPM), utilizes a specially designed filtration vessel coupled directly to an SPE cartridge. The studies were based on surface water samples (from the Vistula River) spiked with pesticides. SPM separation and analyte isolation/concentration were carried out in a special filtration vessel. Pesticides were sorbed both on the SPE cartridge and on the suspended matter. The cartridge and the filter with the suspended matter were extracted separately with a solvent, which enabled the determination of analyte distribution between the two. For organochlorine pesticides, between 3 and 60% of the initial amount was found on the filter, while the recoveries in the filtrate ranged from 30 to 98%. Total recoveries of organochlorine pesticides from surface water samples spiked with pesticides using the method described were high, ranging from 90 to 101%. The amounts of nitrogen/phosphorus containing pesticides recovered from the filter were lower than 2%, while those from the filtrate ranged from 69 to 92%. Total recoveries of nitrogen/phosphorus containing pesticides from surface water samples were high, ranging from 71 to 92%.     

Evaluating effects of wind-induced pressure fluctuations on soil-atmosphere gas exchange at a landfill using stochastic modelling.

The impact of wind turbulence-induced pressure fluctuations at the soil surface on landfill gas transport and emissions to the atmosphere at an old Danish landfill site was investigated using stochastic modelling combined with soil property and gas transport data measured at the site. The impacts of soil physical properties (including air permeability and volumetric water content) and wind-induced pressure fluctuation properties (amplitude and temporal correlation) on landfill gas emissions to the atmosphere were evaluated. Soil-air permeability and pressure fluctuation amplitude were found to be the most important parameters. Wind-induced gas emissions were further compared with gas emissions caused by diffusion and by long-term pressure variations (due to passing weather systems). Here diffusion and wind-induced gas transport were found to be equally important with wind-induced gas transport becoming the most important at lower soil-air contents.     

Conspecific flowers of <Emphasis Type="Italic">Sinapis arvensis</Emphasis> are stronger competitors for pollinators than those of the invasive weed <Emphasis Type="Italic">Bunias orientalis</Emphasis>

Biological invasions can affect the structure and function of ecosystems and threaten native plant species. Since most weeds rely on mutualistic relationships in their new environment, they may act as new competitors for pollinators. Pollinator competition is likely to be density dependent, but it is often difficult to disentangle competition caused by flower quality from effects caused by flower quantity. In order to test the effects of the presence and number of flowers of the invasive weed Bunias orientalis on the insect visitation rates in a native species (Sinapis arvensis), we performed two replacement experiments using plants with standardised flower numbers. The visitation rates in S. arvensis were significantly higher than in B. orientalis and the number of insect visits dropped significantly with increasing density of S. arvensis flowers. These results suggest that intraspecific competition among flowers of S. arvensis is stronger than the competitive effect of alien flowers. As flowers of B. orientalis do not seem to distract visitors from S. arvensis, it is unlikely that pollinator competition between these two plant species plays a crucial role. However, it cannot be excluded that mass blossom stands of B. orientalis may distract flower visitors from native species.     

Exchange of hosts: can agaonid fig wasps reproduce successfully in the figs of non-host <Emphasis Type="BoldItalic">Ficus</Emphasis>?

In the obligate mutualism between figs (Ficus) and their specific pollinators (Chalcidoidea, Agaonidae), each species of fig wasp typically reproduces in figs of a single host species. Host specificity is maintained largely because pollinators are attracted to tree-specific volatiles released from their host figs, but whether the wasps can reproduce if they enter figs of non-host species is unclear. We investigated the reproductive success of Ceratosolen emarginatus (associated with Ficus auriculata) and Ceratosolen sp. (associated with F. hainanensis) in atypical hosts by experimentally introducing foundresses into host and non-host figs. F. auriculata figs entered by Ceratosolen sp. were more likely to abort than if entered by C. emarginatus, but abortion of F. hainanensis figs was not affected by pollinator species. Single C. emarginatus foundresses produced more but smaller offspring in F. hainanensis than in their normal host. Conversely Ceratosolen sp. produced fewer but larger offspring in F. auriculata than in their normal host, probably as a result of having longer to develop. Mean style length differences, relative to the lengths of the wasps’ ovipositors, may have dictated the number of offspring produced, with oviposition made easier by the shorter styles in F. hainanensis figs. Our results imply that, in addition to morphological constraints and tree-specific volatiles, reduced reproductive success in atypical hosts can be another factor maintaining host specificity, but for other species only behavioural changes are required for host switching to occur.     

Geographic variation in resource allocation to the abdomen in geometrid moths

A resource allocation trade-off is expected when resources from a common pool are allocated to two or more traits. In holometabolous insects, resource allocation to different functions during metamorphosis relies completely on larval-derived resources. At adult eclosion, resource allocation to the abdomen at the expense of other body parts can be seen as a rough estimate of resource allocation to reproduction. Theory suggests geographic variation in resource allocation to the abdomen, but there are currently no empirical data on it. We measured resource allocation to the abdomen at adult eclosion in four geometrid moths along a latitudinal gradient. Resource (total dry material, carbon, nitrogen) allocation to the abdomen showed positive allometry with body size. We found geographic variation in resource allocation to the abdomen in each species, and this variation was independent of allometry in three species. Geographic variation in resource allocation to the abdomen was complex. Resource allocation to the abdomen was relatively high in partially bivoltine populations in two species, which fits theoretical predictions, but the overall support for theory is weak. This study indicates that the geographic variation in resource allocation to the abdomen is not an allometric consequence of geographic variation in resource acquisition (i.e., body size). Thus, there is a component of resource allocation that can evolve independently of resource acquisition. Our results also suggest that there may be intraspecific variation in the degree of capital versus income breeding.