Effects of middle-term land reclamation on nickel soil-water interaction: a case study from reclaimed salt marshes of Po River Delta,Italy

Reclaimed salt marshes are fragile environments where water salinization and accumulation of heavy metals can easily occur. This type of environment constitutes a large part of the Po River Delta (Italy), where intensive agricultural activities take place. Given the higher Ni background of Po River Delta soils and its water-soluble nature, the main aim of this contribution is to understand if reclamation can influence the Ni behavior over time. In this study, we investigated the geochemical features of 40 soils sampled in two different localities from the Po River Delta with different reclamation ages. Samples of salt marsh soils reclaimed in 1964 were taken from Valle del Mezzano while soils reclaimed in 1872 were taken nearby Codigoro town. Batch solubility tests and consecutive determination of Ni in pore-water were compared to bulk physicochemical compositions of soils. Bulk Ni content of the studied soils is naturally high, since these soils originated from Po River sediments derived from the erosion of ultramafic rocks. Moreover, it seems that Ni concentration increases during soil evolution, being probably related to the degradation of serpentine. Instead, the water-soluble Ni measured in the leaching tests is greater in soils recently reclaimed compared to the oldest soils. Soil properties of two soil profiles from a reclaimed wetland area were examined to determine soil evolution over one century. Following reclamation, pedogenic processes of the superficial horizons resulted in organic matter mineralization, pH buffer, and a decrease of Ni water solubility from recently to evolved reclaimed soil.     

Odour-based species recognition in two sympatric species of sac-winged bats (<Emphasis Type="Italic">Saccopteryx bilineata,S. leptura)</Emphasis>: combining chemical analyses,behavioural observations and odour preference tests

Combining chemical analysis and odour preference tests, we asked whether two closely related sympatric species of sac-winged bats use odour for species recognition. Males of the two sister species Saccopteryx bilineata and Saccopteryx leptura have pouches containing an odoriferous liquid in their antebrachial wing membrane, which is used in S. bilineata during courtship displays. Although both species occasionally share the same daytime roosts and are morphologically similar, there is no evidence for interbreeding. We compared the production and composition of the wing sac odorant in male S. leptura and S. bilineata and performed odour preference tests with female S. bilineata. Similar to male S. bilineata, male S. leptura cleansed and refilled their wing sacs with secretions, but they spent more time each day in doing so than male S. bilineata. Chemical analysis by gas chromatography and mass spectrometry revealed that male Saccopteryx carried species-specific scents in their wing sacs. Binary choice tests confirmed that female S. bilineata preferred the wing sac scents of male S. bilineata to those of the sister species, suggesting that the species specificity of male wing sac scents maintain the pre-mating isolation barrier between these closely related species.     

Sustainable development in the mining industry: clarifying the corporate perspective

This paper examines sustainable development in the corporate mining context, and provides some guidelines for mining companies seeking to operate more sustainably. There is now a burgeoning literature that examines sustainable development in the context of minerals and mining, most of which is concerned with sustainability at global and national scales. What is often challenging to ascertain, however, from these numerous perspectives on sustainable mineral extraction, minerals and metals recycling, environmental management, and social performance, is how sustainable development applies to mining companies themselves, and what steps a mine must take in order to improve the sustainability of operations. Since mining processes have the potential to impact a diverse group of environmental entities, and are of interest to a wide range of stakeholder groups, there is ample opportunity for the industry to operate more sustainably. Specifically, with improved planning, implementation of sound environmental management tools and cleaner technologies, extended social responsibility to stakeholder groups, the formation of sustainability partnerships, and improved training, a mine can improve performance in both the environmental and socioeconomic arenas, and thus contribute enormously to sustainable development at the mine level.     

Depth and muscle temperature of Pacific bluefin tuna examined with acoustic and pop-up satellite archival tags

Six Pacific bluefin tuna were tracked with ultrasonic telemetry and two with pop-up satellite archival tags (PSATs) in the eastern Pacific Ocean in 1997, 1998, and 1999. Both pressure and temperature ultrasonic transmitters were used to examine the behavior of the 2- to 4-year-old bluefin tuna. The bluefin spent over 80% of their time in the top 40 m of the water column and made occasional dives into deeper, cooler water. The mean slow-oxidative muscle temperatures of three fish instrumented with pressure and temperature transmitters were 22.0–26.1 °C in water temperatures that averaged 15.7–17.5 °C. The thermal excesses in slow-oxidative muscle averaged 6.2–8.6 °C. Variation in the temperature of the slow-oxidative muscle in the bluefin was not correlated with water temperature or swimming speeds. For comparison with the acoustic tracking data we examined the depth and ambient temperature of two Pacific bluefin tagged with pop-up satellite archival tags for 24 and 52 days. The PSAT data sets show depth and temperature distributions of the bluefin tuna similar to the acoustic data set. Swimming speeds calculated from horizontal distances with the acoustic data indicate the fish mean speeds were 1.1–1.4 fork lengths/s (FL s⁻¹). These Pacific bluefin spent the majority of their time in the top parts of the water column in the eastern Pacific Ocean in a pattern similar to that observed for yellowfin tuna. Received: 4 April 2000 / Accepted: 25 October 2000     

Precision determination for the dynamic respirometric index (DRI) method used for biological stability evaluation on municipal solid waste and derived products

Dynamic respiration index (DRI) is an effective respirometric method to measure the biological stability of municipal solid waste (MSW). It allows testing MSW biological stability under standardized conditions and is now used as a routine analytical method. However, the method needs to be studied for precision parameters to ensure the quality of results generated.This work reports on a DRI validation study, detecting repeatability (r) and reproducibility limits (R). To perform the study, 4-6 Italian laboratories took part in an interlaboratory test for the validation of the DRI method on four different municipal solid wastes from different mechanical-biological treatment full-scale plants. Precision values (r and R) of DRI, expressed as relative standard deviation, were in the range of 3.6% and 15.5%, and were acceptable when compared with previous data obtained in another respirometric test. On the other hand, no regressions were found between r and R, and DRI, and as a consequence prediction of precision values was not possible a priori for different DRI levels, unless the same typology of waste was considered.     

Effect of pumpkin root exudates on ex situ polychlorinated biphenyl (PCB) phytoextraction by pumpkin and weed species

Introduction  

A greenhouse experiment was conducted to determine if Cucurbita pepo ssp. pepo (pumpkin) root exudates could increase the uptake of polychlorinated biphenyls (PCBs) into plants. Contaminated soil was pre-treated with pumpkin root exudates by first growing pumpkins in the soil. Plants (pumpkins and weeds) were grown in the pre-treated (root exudate group) and non-treated (control group) contaminated soils. Seeds from five weed species collected from two contaminated sites were germinated in sufficient quantities (n ≥ 6) for three seedlings to be planted in two groups.     

Preliminary risk analysis for LNG tankers approaching a maritime terminal

LNG ships may represent a remarkable risk source, especially when approaching a land terminal, not only due to the possible occurrence of maritime accident, but also since they may represent a suitable target for terrorist attacks. A preliminary risk analysis for LNG ships approaching the Panigaglia terminal is carried out: based on literature data and on the characteristics of the location, a spill originated from a sea accident can be excluded; on the contrary, intentional damages may cause the release of a large amount of LNG, giving rise to a pool fire. Consequence analysis shows that dangerous thermal effects are expected within a radius of 700–1500 m; in the location under exam, the impact on resident population will be negligible, for the most probable attack site, and marginal for an occasionally used anchorage, which should be no longer allowed.     

Single walled carbon nanotube reactivity and cytotoxicity following extended aqueous exposure

Globally carbon nanoparticles are increasingly utilized, yet it is not known if these nanoparticles pose a threat to the environment or human health. This investigation examined ‘as-prepared’, and acid cleaned carbon nanoparticle physicochemical characteristics (by FTIR, TEM, FESEM, UV-VIS and X-ray microanalysis), and whether these characteristics changed following 2.5-7 yr exposure to pH neutral saline or fresh water. To determine if these aqueous aged nanotubes were cytotoxic, these nanotubes were incubated with human epithelial monolayers and analyzed for cell viability (vital staining) and ultrastructural nanoparticle binding/localization (TEM, FESEM). The presence of Ni and Y catalyst, was less damaging to cells than CNT lattice surface oxidation. Extended fresh water storage of oxidized CNTs did not reduce surface reactive groups, nor lessen cell membrane destruction or cell death. However storing oxidized CNTs in saline or NOM significantly reduced CNT-induced cell membrane damage and increased cell survival to control levels.     

Biological effects of diethylene glycol (DEG) and produced waters (PWs) released from offshore activities: A multi-biomarker approach with the sea bass Dicentrarchus labrax

Diethylene glycol (DEG) is largely used during oil and gas exploitation by offshore platforms. The aim of this work was to investigate if this compound induces direct molecular/cellular effects in marine organisms, or indirectly modulate those of produced waters (PWs). Sea bass (Dicentrarchus labrax) were exposed to DEG dosed alone or in combination with PWs from an Adriatic platform. A wide array of analysed biomarkers included cytochrome P450-dependent enzymatic activity, bile metabolites, glutathione S-transferases, acetylcholinesterase, peroxisomal proliferation, antioxidant defences (catalase, glutathione reductase, glutathione peroxidases, glutathione), total oxyradical scavenging capacity, malondialdehyde and DNA integrity (single strand breaks and frequency of micronuclei). Results did not reveal marked effects of DEG, while PWs influenced the biotransformation system, the oxidative status and the onset of genotoxic damages. Co-exposures caused only limited differences of biomarker responses at some experimental conditions, overall suggesting a limited biological impact of DEG at levels normally deriving from offshore activities.