用槐叶苹象甲对塞内加尔河水面的槐叶苹进行有效生物控制

1999年,在毛里塔尼亚和塞内加尔的塞内加尔三角洲下部,槐叶苹(Salvinia moesta)的侵入对当地居民的社会经济状况以及湿地生物多样性构成严重的威胁.分别于2000年5月在塞内加尔和毛里塔尼亚及2001年4月在塞内加尔的河面引进槐叶苹象甲(Cyteobagous salviniae),最终实现了对槐叶苹的有效生物控制.2001年10月,象甲起到的作用已非常明显.植物的颜色由绿色变为深褐色或黑色,槐叶苹最终沉入水底.2001年11～12月对槐叶苹象甲扩散的监控证实了生物控制结果的真实性.至2002年4月已有结论,塞内加尔河畔槐叶苹不再成为问题.     

The Definition of Brownfield

This paper discusses the need for a more robust definition of the term 'brownfield' from a multidisciplinary perspective. It examines the issues involved in constructing an agreed and accepted definition and its importance with regard to UK government policy. Current usage of the term 'brownfield' and related terminology is reviewed. The paper proposes that: a brownfield site is any land or premises which has previously been used or developed and is not currently fully in use, although it may be partially occupied or utilized. It may also be vacant, derelict or contaminated. Therefore a brownfield site is not necessarily available for immediate use without intervention. Interpretation of the terminology incorporated with the definition is presented herein. The definition is subsequently evaluated with respect to the views of different stakeholder groups involved in the redevelopment of brownfield sites.     

Bibliometric analysis of advanced oxidation processes (AOPs) in wastewater treatment: global and Ibero-American research trends

Environmental Science and Pollution Research - Advanced oxidation processes (AOPs) constitute a developing area of particular interest for researchers in different fields due to their broad range...     

Robinsonecio gerberifolius as a sentinel organism for atmospheric pollution by heavy metals in several sites of Mexico city and its metropolitan area

Environmental Science and Pollution Research - Evaluate the effect of heavy metals (HM) on sentinel organisms such as vascular plants represent a model to estimate toxic hazard due to environmental...     

Variation in sex pheromone emission does not reflect immunocompetence but affects attractiveness of male burying beetles—a combination of laboratory and field experiments

Life history theory predicts a trade-off between male sexual trait expression and immunocompetence. Using burying beetles, Nicrophorus vespilloides, as a model, we investigated the relationship between male immune function, sex pheromone emission, and attractiveness under field conditions. In the first experiment, we tested whether there is a positive correlation between immune capacity, sex pheromone characteristics (quantity, relative composition, and time invested in pheromone emission), and male attractiveness. As a measurement of immune capacity, we used an individual’s encapsulation ability against a novel antigen. In the second experiment, we specifically examined whether a trade-off between chemical trait expression and immune function existed. To this end, we challenged the immune system and measured the subsequent investment in sex pheromone emission and the attractiveness of the male under field conditions. We found that a male’s immunocompetence was neither related to the emission of the male’s sex pheromone nor to its attractiveness in the field. Furthermore, none of the immune-challenge treatments affected the subsequent investment in pheromone emission or number of females attracted. However, we showed that the same males that emitted a high quantity of their sex pheromone in the laboratory were able to attract more females in the field. Our data suggest that the chemical signal is not a reliable predictor of a male’s immunocompetence but rather is a general important fitness-related trait, with a higher emission of the sex pheromone measured in the laboratory directly affecting the attractiveness of a male under field conditions.     

Determination of renewable energy yield from mixed waste material from the use of novel image analysis methods

Two novel techniques are presented in this study which together aim to provide a system able to determine the renewable energy potential of mixed waste materials. An image analysis tool was applied to two waste samples prepared using known quantities of source-segregated recyclable materials. The technique was used to determine the composition of the wastes, where through the use of waste component properties the biogenic content of the samples was calculated. The percentage renewable energy determined by image analysis for each sample was accurate to within 5% of the actual values calculated. Microwave-based multiple-point imaging (AutoHarvest) was used to demonstrate the ability of such a technique to determine the moisture content of mixed samples. This proof-of-concept experiment was shown to produce moisture measurement accurate to within 10%. Overall, the image analysis tool was able to determine the renewable energy potential of the mixed samples, and the AutoHarvest should enable the net calorific value calculations through the provision of moisture content measurements. The proposed system is suitable for combustion facilities, and enables the operator to understand the renewable energy potential of the waste prior to combustion.     

An analysis of the composition and metal contamination of plastics from waste electrical and electronic equipment (WEEE)

The compositions of three WEEE plastic batches of different origin were investigated using infrared spectroscopy, and the metal content was determined with inductively coupled plasma. The composition analysis of the plastics was based mainly on 14 samples collected from a real waste stream, and showed that the major constituents were high impact polystyrene (42 wt%), acrylonitrile–butadiene–styrene copolymer (38 wt%) and polypropylene (10 wt%). Their respective standard deviations were 21.4%, 16.5% and 60.7%, indicating a considerable variation even within a single batch. The level of metal particle contamination was found to be low in all samples, whereas wood contamination and rubber contamination were found to be about 1 wt% each in most samples. In the metal content analysis, iron was detected at levels up to 700 ppm in the recyclable waste plastics fraction, which is of concern due to its potential to catalyse redox reactions during melt processing and thus accelerate the degradation of plastics during recycling. Toxic metals were found only at very low concentrations, with the exception of lead and cadmium which could be detected at 200 ppm and 70 ppm levels, respectively, but these values are below the current threshold limits of 1000 ppm and 100 ppm set by the Restriction of Hazardous Substances directive.     

Effects of formalin on some biomarker activities of earthworms pre-exposed to temephos

Despite its negative effects, formalin has been often used for the expulsion of earthworms due to its high efficiency; however it is not known whether it will affect any significant measurable molecular processes in sampled earthworms. The aim of this research was to investigate effects of formalin on the activities of chosen molecular biomarkers in Eisenia andrei earthworms previously exposed to temephos. Additionally, the inhibitory effect of temephos, hitherto evaluated only on laboratory-bred earthworm species, was confirmed on two earthworm species obtained from their natural environment – Dendrobaena octaedra and Lumbricus rubellus. Earthworms were first exposed to the sub-lethal concentration of temephos for 2 h and then to formalin 15 min in order to simulate the sampling procedure. Besides acetylcholinesterase (AChE) inhibition – a known biomarker of exposure to organophosphate insecticides – the concentration of oximes and the activities of catalase (CAT) and efflux pump were measured. Results showed that in all species temephos caused inhibition of AChE and CAT activity. Exposure of E. andrei to formalin caused inhibition of AChE, however after post-exposure to formalin for 15 min significant increase in AChE activity was recorded. Similar results were obtained with the measurement of oximes concentrations. Exposure to only formalin and combination of temephos (2 h) and formalin (15 min) led to an increase in the CAT activity. The obtained results showed that exposure to formalin during the sampling could affect measured molecular biomarkers and also may change effects caused by exposure to temephos.