Coal rejects — a wasted resource?

The paper outlines potential uses for coal washery rejects. It considers in detail the use of fluidized-bed combustion as a means of lessening rejects disposal problems, as a method of recovering energy for drying, steam raising and electricity production and as a source of ash as a substitute for natural aggregate. Considerable technical information is now available on the use of fluidized beds for these purposes and the paper concludes that it is appropriate to consider a more detailed, site-specific, evaluation.     

糠醛生产企业废水处理措施

使用糠醛塔下污水循环利用装置，糠醛生产污水得到全部综合利用，不产生二次污染，节省了能源消耗，减轻了环境污染，实现了“节能减排”的目标。     

Natural organic matter controls metal speciation and toxicity for marine organisms: a review

Environmental Chemistry Letters - Heavy metals are occurring in the aquatic environment as the result of natural or anthropogenic inputs, and depending on concentration, availability and resilience...     

镉对植物光合作用的影响

本文从光合作用色素、光合组织、光合作用过程、光合速率等方面概述了近些年来 Cd对植物光合作用影响的研究进展 ,并结合我们的研究进行了讨论。     

Influence of hydrodynamic conditions on the production and fate of Posidonia oceanica in a semi-enclosed shallow basin (Stagnone di Marsala, Western Sicily)

An integrated approach using hydrodynamic and transport numerical models, lepidochronology and stable isotope analysis was used to investigate how local hydrodynamic conditions influence the primary production and fate of the seagrass Posidonia oceanica in a Mediterranean semi-enclosed marine system (Stagnone di Marsala). The water mass exchange aptitude of different sectors of the basin was analysed, and data collected were used to select two sectors (colonized by Posidonia oceanica showing the lowest and highest water exchange values) for biological analyses. According to the mean dispersal coefficient differences simulated by the hydrodynamic model, growth rate and primary production of P. oceanica differed between sectors, with average values lower in the central sector where water exchange is lower than in the southern sector. Although P. oceanica coverage and primary production were higher in the southern sector, carbon and nitrogen stable isotope analysis suggests that the transfer of seagrass organic matter to higher trophic levels of the food web was higher in the central sector. The possibility of a link between hydrodynamism, production and fate of organic matter is proposed to explain the observed patterns.     

Determination of living and active bacterioplankton: a comparison of methods

The purpose of this study was the quantification, through the comparison of different methods, of viable and metabolically active bacteria in marine environments. To quantify the living and active bacterioplankton fractions, we compared the total cell count (TC using DAPI staining), plate count on marine agar (CFU), and three viability-staining methods: nucleoid-containing cell count (NuCC), Live/Dead staining procedure (L/D) and direct viable count (DVC). With respect to TC (mean value 3.0 ± 2.3 × 10⁵ cell ml^-1) CFU represented less than 0.1% and DVC cells 1%, both showing significant differences. NuCC and L/D cells were 18.0% and 15.9% of TC, respectively, showing no significant differences and higher percentages in the Ionian Sea than the Adriatic Sea. Moreover, NuCC and L/D were two orders of magnitude greater than the culturable fraction, while active cells (DVC) exceeded CFU by one order of magnitude. The comparison of different staining methods allowed us to confirm the simultaneous presence of different physiological states within the bacterial population in natural marine environments. The NuCC and L/D methods gave comparable values to those of other authors, while the DVC procedure gave lower values than previously reported. This research provides information on the fraction of living and/or metabolically active bacteria in aquatic ecosystems. Since each method has its own detection limits, the study highlights the need to simultaneously compare the different methods to validate their results.     

Oncogenic Papillomavirus and Polyomavirus in Water Environments: Is There a Potential for Waterborne Transmission?

Waterborne exposure to human viruses through contact with sewage-contaminated water environments can result in infections associated with a wide range of illnesses. Gastrointestinal symptoms are the most commonly encountered manifestations of waterborne viral illness. Respiratory diseases, neurological diseases and paralysis can also occur. Whether viral infections resulting in health outcomes like cancer might also be transmitted by the waterborne route is unknown. Recently, viruses belonging to two oncogenic groups—Human Papillomaviruses (HPVs) and Human Polyomaviruses (HPyVs)—have been detected in urban sewages worldwide. The latter have also been identified in other water environments. HPVs are epitheliotropic viruses responsible for several diseases of skin and mucosae, from common warts to squamous intraepithelial lesions that can either heal or progress to invasive carcinoma of the cervix, vulva, vagina, penis, anus or oropharynx. Human PyVs infect different tissues and organs, causing infections that are usually subclinical in immunocompetent individuals but can be serious in immunocompromised hosts. These pathogens belong to a family of DNA tumour viruses. Merkel cell polyomavirus, a HPyV identified in recent years, has attracted much attention due to its link with a rare and aggressive form of human cancer. Merkel cell carcinoma, the incidence of which has tripled over the past two decades. JC polyomavirus and BK polyomavirus are also potentially oncogenic. The observed abundance and wide dissemination of HPVs and HPyVs in water environments strongly suggest the need to shed light on the fate of these viruses in water environments and to elucidate their potential for waterborne transmission. Such information is essential for the improvement of wastewater management programs in terms of both sewage treatment and water quality surveillance.