Signals for damage control: web decorations in <Emphasis Type="Italic">Argiope keyserlingi</Emphasis> (Araneae: Araneidae)

Orb web spiders of the genus Argiope are permanently located at the hub of the orb web and are thus vulnerable to changing environmental conditions. Severe damage to the web by non-prey animals can have a significant impact on survival, through the cost of producing expensive silk and the loss of foraging opportunities. Thus, selection should favor web protection mechanisms, and the conspicuous web decorations, typical of Argiope spiders, may play a role. Decorated webs suffer less damage than undecorated webs, consistent with the view that they advertise the presence of the web to non-prey animals that may damage the web. However, whether spiders respond to web damage by increasing investment in web decorations has not been investigated. We subjected adult St. Andrew's Cross spider (Argiope keyserlingi) females to three levels of web damage and recorded their subsequent web-decorating behavior. Mild damage, similar to that caused by impacting prey, did not affect either web building or decorating behavior. However, spiders subjected to substantial web damage both reduced the size of subsequent webs and increased investment in web decoration size. These data are consistent with an advertising role of web decorations.     

Brood parasitism disproportionately increases nest provisioning and helper recruitment in a cooperatively breeding bird

Obligate avian brood parasites lay their eggs in nests of other species (hosts), which raise parasitic young. Parasitic nestlings are likely to influence host’s parental behaviours as they typically beg for food more vigorously than young host for a given hunger level. However, few studies have tested this idea, with conflicting results. These prior studies were largely limited to biparental hosts, but little is known about the effect of brood parasitism on parental behaviours in hosts that breed cooperatively. We followed a multimodel approach to examine the effect of brood parasitism on nest provisioning and helper recruitment in the baywing (Agelaioides badius), a cooperative breeder parasitised by screaming (Molothrus rufoaxillaris) and shiny (Molothrus bonariensis) cowbirds. Multimodel inference results indicated that feeding visits increased with nestling age, cooperative group size and number of cowbird nestlings in the brood. Brood size had little influence on feeding visits, which further suggests that baywings adjusted their provisioning effort in response to cowbird parasitism. In addition, nests parasitised artificially with shiny cowbird eggs or hatchlings recruited more helpers than unmanipulated nests having only host or screaming cowbird young. Our results provide novel evidence that brood parasitism and cooperative breeding interact in determining the levels of nest provisioning.     

Heavy metal bioaccumulation by the bryophyte Scleropodium purum at three French sites under various influences: rural conditions, traffic, and industry

An active biomonitoring of the heavy metals pollution experiment was undertaken by means of the bryophyte species Scleropodium purum transplanted at three different sites exposed to rural, traffic, or industrial influences. Concentrations of about 40 elements in S. purum were determined by instrumental neutron activation analysis and inductively coupled plasma mass spectrometry. Accumulation rates of heavy metals were determined in the three sites. These accumulation rates in polluted sites were matched together and also to those recorded at the rural site. The changes of the accumulation rate of heavy metals in S. purum versus their concentrations in PM₁₀ particles simultaneously collected above show some different accumulation properties of S. purum according to elements and sites. S. purum has a weak efficiency in the three sites to accumulate elements like V, Cr, Cu, Zn, As, Se, Sb, and Pb originating from atmospheric hot sources generally enriched in particulates matter (PM₁₀), whereas it is particularly high for Br, Th, and Rb. For other elements, Co, La, Ce, and Hf, and rare earth elements, Fe, Sr, Nb, Ti, Al, and Sc, the collection efficiency by S. purum is intermediate. In the industrial site Dunkerque, a magnification of the collection efficiency by S. purum for elements originating from steel and aluminum productions and petroleum refinement suggests that these metals could be enriched in coarse particles with a better accumulation by the bryophyte with respect to PM10.     

Modulation of attention and urgent decisions by affect-laden roadside advertisement in risky driving scenarios

In road safety literature the effects of emotional content and salience of advertising billboards have been scarcely investigated. The main aim of this work was to uncover how affect-laden roadside advertisements can affect attention – eye-movements – and subsequent risky decisions – braking – on the Honda Riding Trainer motorcycle simulator. Results indicated that the number of fixations and total fixation time elicited by the negative and positive emotional advertisements were larger than the neutral ones. At the same time, negative pictures got later gaze disengagement than positive and neutral ones. This attentional capture results in less eye fixation times on the road relevant region, where the important driving events happen. Finally, the negative emotional valence advertisements sped up braking on subsequent risky situations. Overall results demonstrated how advertisements with emotional content modulate attention allocation and driving decisions in risky situations and might be helpful for designing roadside advertisements regulations and risk prevention programs.     

Nucella lapillus L. imposex levels after legislation prohibiting TBT antifoulants: temporal trends from 2003 to 2008 along the Portuguese coast

Nucella lapillus (dog whelk) imposex levels were assessed along the mainland Portuguese coast in 2006 and 2008 and were compared with available data from 2003 for the same area. Given that specimen size has been described as a factor inducing variation in some of the imposex assessment indices, and thus resulting in less reliable results, new monitoring and data analysis procedures are described and applied to study change of imposex levels from 2003 to 2008. A significant decline in imposex intensity was observed in the study area during the study period, and the Portuguese coast ecological status (under the terms defined by the OSPAR Commission) notably improved after 2003, confirming the effectiveness of the Regulation (EC) No. 782/2003 in reducing TBT pollution. Nevertheless, N. lapillus populations are still extensively affected by imposex, and fresh TBT inputs were detected in seawater throughout the coast in 2006. These recent inputs are attributed to vessels still carrying TBT antifoulants applied before 2003, as their presence in vessels was only forbidden in 2008. Considering that Regulation (EC) No. 782/2003 is an anticipation of the IMO global ban entered into force in September 2008, a worldwide-scale decrease in TBT pollution can be expected in the near future.     

Amplified ribosomal DNA restriction analysis as a routine tool to assess toxicant driven changes in hindgut bacterial populations of Porcellio dilatatus (Crustacea: Isopoda)

Changes in saprophytic organism's gut microbial communities may present a threat to organic matter breakdown which can ultimately lead to soil function impairment. In this study, Amplified Ribosomal DNA Restriction Analysis (ARDRA) was evaluated as a potential simple molecular tool to assess shifts in bacterial community structure in hindgut populations of Porcellio dilatatus exposed to contaminated food. This prospective tool can also be used for a variety of purposes and samples prior to the use of more specific and sophisticated methods.     

Biofiltration of fugitive methane emissions from landfills using scum from municipal wastewater treatment plants as alternative substrate

Journal of Material Cycles and Waste Management - Biofilters have been recognized as a key technology in the mitigation of greenhouse gases (GHG) emitted by landfills. This study aimed to evaluate...     

Bio-based films/nanopapers from lignocellulosic wastes for production of added-value micro-/nanomaterials

Environmental Science and Pollution Research - The growing demand for products with lower environmental impact and the extensive applicability of cellulose nanofibrils (CNFs) have received...     

Physiological responses of beet and cabbage plants exposed to copper and their potential insertion in human food chain

Environmental Science and Pollution Research - Copper (Cu) can be toxic to vegetables when it is absorbed and accumulated at large concentrations, a fact that increases the risk of excessive...