Who’s where? Ecological uncertainty shapes neophobic predator avoidance in Trinidadian guppies

Behavioral Ecology and Sociobiology - Behavioural diversity is a basic component of biodiversity, with implications in ecological interactions at the intra- and interspecific levels. The...     

Seasonal variations of heavy metals in central Greenland snow deposited from 1991 to 1995

To better assess the seasonality in the fallout of heavy metals to central Greenland, a continuous series of 68 snow samples has been collected at a remote site in the Summit area from a 2.7 m pit using ultraclean sampling procedures. This covers a continuous four year time period from spring 1991 to spring 1995. Co, Cu, Zn, Mo, Rh, Pd, Ag, Cd, Sb, Pt, Pb, Bi and U were determined using ultrasensitive inductively coupled plasma sector field mass spectrometry under clean room conditions. In addition we also determined Al by graphite furnace atomic absorption spectrometry and Na+, Ca2+, SO4(2-), MSA and oxalate by ion chromatography, species that will assist in the interpretation of the trace metal data. The data show pronounced inter- and intra-annual variations, with large differences in the amplitude of these variations for the element studied, with few clear seasonality patterns. Generally, high concentrations are observed in the spring snow layers, while much lower concentrations are typical of summer snow layers. Significant correlations are observed between Co, Cu, Zn, Ag and Sb, while Pt, Pd and Rh show no correlation with the other metals. Crustal enrichment factors show that while the crustal dust contribution is probably important for some metals for part of the year (spring), anthropogenic inputs are as important in many instances. Pronounced intra-annual variations are observed for some metals, in particular Pt. The variations observed for this metal parallel fairly closely changes in Russian Pt production, which points to emissions from smelters in the Russian Arctic as likely sources for Pt.     

Conifer needles as passive biomonitors of the spatial and temporal distribution of DDT from a point source

Needles of two conifer species, Picea abies and Pinus nigra, were used as passive samplers for monitoring air contamination by sampling at increasing distances from a suspected point source of DDT. Needle concentrations declined with increasing distance downwind of the point source allowing to identify spatial and temporal trends of accumulation. This suggested that conifer needles are effective biomonitors of contamination levels in areas characterized by the presence of semi-volatile substances. Differences in uptake were apparent between the species. Needle morphology and structure were studied with scanning electron microscope (SEM) as were dimensional parameters (surface area, volume). The results suggest that the concentrations depend on a mechanism involving the inner structure of the needles, specifically the number and accessibility of resin channels rather than their surface area. Pine needles have more channels with greater accessibility than spruce. The results suggest that spruce is more suitable for short term measurement while pine for determining long term cumulative exposure.     

Environmental Risks of Pesticides Versus Genetic Engineering for Agricultural Pest Control

Despite the application of 2.5 million tons ofpesticides worldwide, more than 40% of all potentialfood production is lost to insect, weed, and plantpathogen pests prior to harvest. After harvest, anadditional 20% of food is lost to another group ofpests. The use of pesticides for pest control resultsin an estimated 26 million human poisonings, with220,000 fatalities, annually worldwide. In the UnitedStates, the environmental and public health costs forthe recommended use of pesticides total approximately$9 billion/yr. Thus, there is a need for alternativenon-chemical pest controls, and genetic engineering(biotechnology) might help with this need. Diseaseand insect pest resistance to various pests has beenslowly bred into crops for the past 12,000 years;current techniques in biotechnology now offeropportunities to further and more rapidly improve thenon-chemical control of disease and insect pests ofcrops. However, relying on a single factor, like theBacillus thuringiensis toxin that has beeninserted into corn and a few other crops for insectcontrol, leads to various environmental problems,including insect resistance and, in some cases, athreat to beneficial biological control insects andendangered insect species. A major environmental andeconomic cost associated with genetic engineeringapplications in agriculture relates to the use ofherbicide resistant crops (HRC). In general, HRCtechnology results in increased herbicide use but noincrease in crop yields. The heavy use of herbicidesin HRC technology pollutes the environment and canlead to weed control costs for farmers that may be2-fold greater than standard weed control costs. Therefore, pest control with both pesticides andbiotechnology can be improved for effective, safe,economical pest control.     

Sensory complementation and the acquisition of predator recognition by salmonid fishes

Following disturbance, some aquatic prey species release chemicals that act as a warning cue and increase vigilance in nearby conspecifics. Such disturbance cues evoke consistent low intensity anti-predator responses. In contrast, alarm cues from injured conspecifics often evoke stronger intensity responses in prey animals. In this study, we test the sensory complement hypothesis, which suggests that multiple cues act in an additive or synergistic fashion to provide additional information for risk assessment by prey. In the first experiment, we showed that juvenile rainbow trout pre-exposed to disturbance cues respond to a given concentration of damage-released alarm cues with a higher intensity of response than the trout that were pre-exposed to cues from undisturbed conspecifics. The two cues acted in an additive fashion. In the second experiment, we demonstrated that disturbance cues alone were not enough to elicit a conditioned response to the odour of a novel predator. We also showed that while disturbance cues elicit an increase in the response of trout to alarm cues, this increase does not translate into a stronger learned response to the predator when the predator odour is paired with alarm cues. Future studies should take into account sensory complementation to avoid underestimating the responses of prey to predators.     

Occurrence of imidacloprid,carbendazim, and other biocides in Italian house dust: Potential relevance for intakes in children and pets

The occurrence of pesticides intended for non-agricultural use was investigated in 206 dust samples drawn from vacuum-cleaner bags from residential flats in Italy. The multi-residue analysis targeted on 95 different active principles was performed with UPLC-MS/MS, with a Limit of Quantification (LOQ) of 0.008 μg/g dry weight. The results indicated the presence of imidacloprid (IMI) and carbendazim (CARB) in 30% and 26% of the samples, with a mean and P95 concentration between 1.6 and 39 and between 0.08 and 4.9 μg/g, respectively. Combined presence of two biocides was noted in 19.4% samples, of three biocides in 9.2% samples, of four biocides in 3.4% samples, and of five and six biocides in 0.5% and 1% samples, respectively. According to the estimated dust intake in infants/toddlers aged 6–24 months (16–100 mg d^?1) and cats (200 mg d^?1), it was possible to obtain risk characterization with respect to the Acceptable Daily Intake (ADI) for IMI of 0.060 mg/kg body weight (bw) proposed by the European Food Safety Authority (EFSA) and the chronic Population Adjusted Dose (cPAD) of 0.019 mg/kg bw d^?1 by US-EPA. Under the worst-case scenario, the presence of IMI in dust indicates potential exceedance of the cPAD in kittens, to be considered as sentinel also accounting for combined exposure. This study highlights the relevance of consumer empowerment about the responsible use of pesticides as biocidal products in indoor environment.     

POEMS: A Case Study of an Italian Wine-Producing Firm

Over the last decade, researchers paid much attention to concepts such as Design for Environment, Extended Producer Responsibility, Responsible Chain Management, and Eco-design. Many management tools and standards (such as EMAS, ISO 14001, LCA, EPD, Ecolabel) have been developed to support companies in the evaluation and management of their environmental performance and to pursue continual environmental improvement. The more recent development of the aforesaid fields looks at interorganizational environmental management. Such an approach can complement the more traditional intraorganizational corporate environmental management approaches and tools. A typical example of this new trend is the Product Oriented Environmental Management System (POEMS), which represents the natural evolution of the above-mentioned tools, combining the features of EMS, EPD and Ecolabel. Although the structure of the POEMS is still not standardized, many experimental applications have yet been carried out in Europe. In developing a POEMS, a company needs to determine all of the environmental impacts caused at all life-cycle stages of the product and, ideally, to reduce all of them through a continual commitment. The aim of the present study was to perform a survey of the developed POEMS models and to analyze their peculiarities and drawbacks in the application to Small and Medium Enterprises. A case study regarding an Italian winery company is presented. The study analyzes the structure and the activities of the examined firm, in order to estimate direct and indirect environmental impacts following a life-cycle approach. The chosen functional unit is a 0.75-L bottle of red wine. The article also suggests some solutions to improve the environmental performances of the firm’s products.     

Threat-sensitive generalization of predator recognition by larval amphibians

Despite the importance of acquired predator recognition in mediating predator–prey interactions, we know little about the specific characteristics that prey use to distinguish predators from non-predators. Recent experiments with mammals and fish indicate that some prey lacking innate predator recognition have the ability to display anti-predator responses upon their first encounter with those predators if they are similar to predators that the prey has recently learned to recognize. This phenomenon is referred to as generalization of predator recognition. In this experiment, we documented for the first time that larval amphibians (woodfrog, Rana sylvatica) have the ability to generalize the recognition of known predators to closely related novel predators. Moreover, we demonstrated that this ability is dependent on the level of risk associated with the known predator. When red-bellied newt, Cynops pyrrhogaster (known predator), was paired with simulated low risk, tadpoles displayed fright responses to newts and novel tiger salamanders, Ambystoma tigrinum, but not to novel African clawed frogs, Xenopus laevis. However, when the newt was paired with simulated high risk, tadpoles generalized their responses to both tiger salamanders and African clawed frogs. Larval anurans seem to have a wider generalization frame than other animals.     

The role of a steel plant in north-west Italy to the local air concentrations of PCDD/Fs

Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) are ubiquitous contaminants, mainly released into the environment during combustion processes (point sources), but also from other sources (traffic, uncontrolled combustion).This study aims at investigating the contribution of a steel plant in NW Italy (700 000 tons of steel year⁻¹) to the air concentrations of PCDDs/PCDFs at local level, through the analysis of measured, modelled and literature data. The study was carried out in an area of 600 km², using air quality data measured by the institutional monitoring network, data obtained from AERMOD simulations and literature data.The measured air concentrations were consistent with literature values for similar areas, and both the homologue profiles and PCA analyses showed a clear distinction between the monitoring stations and the source profiles.All the previous results were confirmed by the air dispersion model (AERMOD), that predicted PCDD/F air concentrations due to the steel plant from four to two orders of magnitude lower than those measured in the monitoring stations, highlighting the presence of other sources.This study outlines the limited influence of the source in the local PCDD/F air concentrations and at the same time the usefulness of a joint analysis of measured, literature and calculated data to correctly evaluate the role of a source to the local pollution. The study also highlights the usefulness of AERMOD as a complementary tool to define the correct placement of monitoring stations and to locate those areas expected to have the highest air concentrations deriving from a source.     

Resource Consumption and Environmental Impacts of the Agrofood Sector: Life Cycle Assessment of Italian Citrus-Based Products

Food production and consumption cause significant environmental burdens during the product life cycles. As a result of intensive development and the changing social attitudes and behaviors in the last century, the agrofood sector is the highest resource consumer after housing in the EU. This paper is part of an effort to estimate environmental impacts associated with life cycles of the agrofood chain, such as primary energy consumption, water exploitation, and global warming. Life cycle assessment is used to investigate the production of the following citrus-based products in Italy: essential oil, natural juice, and concentrated juice from oranges and lemons. The related process flowcharts, the relevant mass and energy flows, and the key environmental issues are identified for each product. This paper represents one of the first studies on the environmental impacts from cradle to gate for citrus products in order to suggest feasible strategies and actions to improve their environmental performance.